One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric

On 2019/11/14 12:20 p.m., wrote:
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric


I'd say it is unlikely the capacitor is the problem - normally these are
used to smooth the Vcc to the chips. You say there are custom chips on
the board, so depending on if you can get schematics or not then you may
be looking at the rest of the circuits.

Regular electrolytic caps are rarely used for critical timing, rather
they would use a tantalum cap if the value was important.

If you want to check the ESR then Bob Parker's Blue ESR meter kit is not
a bad way to go...available here (flippers.com - shameless plug!) and
there...

However I don't think the cap is responsible for your problems.

Have you tried simply reseating the chips and connectors to the PCB and
any readouts, sensors, etc. in case it may be that simply reseating
plugs fixes the problem?

If the problem is only apparent after the machine has been on a while
have you checked the temperature of the logic? Chips don't like being
more than 50C by and large, and the cooler they run the better. A heat
gun and some cold spray may help find the sensitive IC as you say the
problem goes away when the system is warm.

John :-#)#

In article ,
says...
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.



The capacitor probably only costs a few dollars at most. Just replace
it and see if the board comes back to life. That is see if the machine
acts normally.

On Thu, 14 Nov 2019 13:03:28 -0800, John Robertson
wrote:

On 2019/11/14 12:20 p.m., wrote:
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric


I'd say it is unlikely the capacitor is the problem - normally these are
used to smooth the Vcc to the chips. You say there are custom chips on
the board, so depending on if you can get schematics or not then you may
be looking at the rest of the circuits.

Regular electrolytic caps are rarely used for critical timing, rather
they would use a tantalum cap if the value was important.

If you want to check the ESR then Bob Parker's Blue ESR meter kit is not
a bad way to go...available here (flippers.com - shameless plug!) and
there...

However I don't think the cap is responsible for your problems.

Have you tried simply reseating the chips and connectors to the PCB and
any readouts, sensors, etc. in case it may be that simply reseating
plugs fixes the problem?

If the problem is only apparent after the machine has been on a while
have you checked the temperature of the logic? Chips don't like being
more than 50C by and large, and the cooler they run the better. A heat
gun and some cold spray may help find the sensitive IC as you say the
problem goes away when the system is warm.

John :-#)#
Greetings John,
Actually the machine starts to work after it has warmed up for a
while. I have tried the whole contact cleaning route several times and
it has had no effect on this machine.
Today I tried out two boards that I got used from eBay. One worked
and the other, whil it indexed then turret OK would not allow
programmed speed changes.
The speed change fault is mysterious to me and it has happened on
another board. The mystery is because of what the fault does.
Niormally speed changes while running a program can only happen from
programmed speed changes or from the constant surface speed command.
But when the board goes bad then the spindle speed can only be
controlled by the dial used for speed changes when in jog mode. And
that dial normally does not work when running a program.
I checked all the parameters and they have not changed. And the
EPROMs that hold the ladder programs for the machine are not affected.
In fact, I have to change them from board to board.
Speaking of EPROMs, I am ordering a GQ-4x4 programmer so I can copy
my EPROMs. I am really afraid I will destroy one one of these days. I
have lots of 2716 and 27C16 EPROMs that I can erase and re-program.
The machine has in it some 2716 and 2516 devices and I was told that
the 2516 devices should not be used. I am hoping the programmer can
read the 2516 devices.
Thanks,
Eric

On Thu, 14 Nov 2019 17:35:48 -0500, Ralph Mowery
wrote:

In article ,
says...
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.



The capacitor probably only costs a few dollars at most. Just replace
it and see if the board comes back to life. That is see if the machine
acts normally.

Yeah, I am gonna do that. I just won't get my hopes up.
Eric

On Thursday, November 14, 2019 at 3:20:47 PM UTC-5, wrote:
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric

I work on a lot of industrial equipment for two local machine shops, and electros do go.

They bring me the suspected boards but I have them well trained to first heat the boards with a heat gun (without crisping them) and report if the normal operation is restored when heated.

If so, the first thing to get checked is the electros. I pull every one and test them for value, ESR, and dielectric absorption. Testing ESR in circuit on many modern circuit boards is a waste of time.

99% of the time a board that works normally when heated has a lazy electrolytic.

If the electro replacement doesn't fix it, try cooling individual parts to see if you can get it to act up.

In article ,
says...
eport if the normal operation is restored when heated.

If so, the first thing to get checked is the electros. I pull every one and test them for value, ESR, and dielectric absorption. Testing ESR in circuit on many modern circuit boards is a waste of time.




Once pulled, you might as well not test them, just replace them.

You may want to test the new ones before you put them in.

On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:

99% of the time a board that works normally when heated has a lazy
electrolytic.

Or a dry solder joint somewhere on the board.

If the electro replacement doesn't fix it, try cooling individual parts
to see if you can get it to act up.

Good call. For which you can use stuff like 'pipe freeze' or 'Arctic
freeze' with the fine straw inserted - sold at your local plumbing
supplies. Clean the board with IPA afterwards.




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protocols constitutes acceptance of this condition.

On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:


If so, the first thing to get checked is the electros. I pull every one
and test them for value, ESR, and dielectric absorption. Testing ESR in
circuit on many modern circuit boards is a waste of time.

Why so?



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This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

On Friday, November 15, 2019 at 4:45:16 AM UTC-5, Cursitor Doom wrote:
On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:


If so, the first thing to get checked is the electros. I pull every one
and test them for value, ESR, and dielectric absorption. Testing ESR in
circuit on many modern circuit boards is a waste of time.

Why so?


Too many circuits these days use a small value SMD multi layer chip capacitor bypassing an electrolytic. These chip caps have ESR figures as low or lower than most electrolytics you're likely to run across despite being small value caps.

On Thursday, November 14, 2019 at 11:14:21 PM UTC-5, Ralph Mowery wrote:
In article ,
says...
eport if the normal operation is restored when heated.

If so, the first thing to get checked is the electros. I pull every one and test them for value, ESR, and dielectric absorption. Testing ESR in circuit on many modern circuit boards is a waste of time.




Once pulled, you might as well not test them, just replace them.

You may want to test the new ones before you put them in.


If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with.

Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data. Sometimes you just have to replace a board.

On 2019/11/14 4:01 p.m., wrote:
On Thu, 14 Nov 2019 13:03:28 -0800, John Robertson
wrote:

On 2019/11/14 12:20 p.m., wrote:
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric


I'd say it is unlikely the capacitor is the problem - normally these are
used to smooth the Vcc to the chips. You say there are custom chips on
the board, so depending on if you can get schematics or not then you may
be looking at the rest of the circuits.

Regular electrolytic caps are rarely used for critical timing, rather
they would use a tantalum cap if the value was important.

If you want to check the ESR then Bob Parker's Blue ESR meter kit is not
a bad way to go...available here (flippers.com - shameless plug!) and
there...

However I don't think the cap is responsible for your problems.

Have you tried simply reseating the chips and connectors to the PCB and
any readouts, sensors, etc. in case it may be that simply reseating
plugs fixes the problem?

If the problem is only apparent after the machine has been on a while
have you checked the temperature of the logic? Chips don't like being
more than 50C by and large, and the cooler they run the better. A heat
gun and some cold spray may help find the sensitive IC as you say the
problem goes away when the system is warm.

John :-#)#
Greetings John,
Actually the machine starts to work after it has warmed up for a
while. I have tried the whole contact cleaning route several times and
it has had no effect on this machine.
Today I tried out two boards that I got used from eBay. One worked
and the other, whil it indexed then turret OK would not allow
programmed speed changes.
The speed change fault is mysterious to me and it has happened on
another board. The mystery is because of what the fault does.
Niormally speed changes while running a program can only happen from
programmed speed changes or from the constant surface speed command.
But when the board goes bad then the spindle speed can only be
controlled by the dial used for speed changes when in jog mode. And
that dial normally does not work when running a program.
I checked all the parameters and they have not changed. And the
EPROMs that hold the ladder programs for the machine are not affected.
In fact, I have to change them from board to board.
Speaking of EPROMs, I am ordering a GQ-4x4 programmer so I can copy
my EPROMs. I am really afraid I will destroy one one of these days. I
have lots of 2716 and 27C16 EPROMs that I can erase and re-program.
The machine has in it some 2716 and 2516 devices and I was told that
the 2516 devices should not be used. I am hoping the programmer can
read the 2516 devices.
Thanks,
Eric


Hi Eric,

If those are TI TMS2516 then they are equivalent to regular Intel 2716s.
The TMS2716 by TI had a triple supply and A10 was displaced.

TMS2716 vs regular 2716s

https://www.dropbox.com/s/7xaz0b829b...s2716.jpg?dl=0

TMS2516 (Thanks JRock for hosting):

http://www.jrok.com/datasheet/TMS2516.pdf

I don't know about the dependability of the TMS2516, but I would back up
ALL EPROMs just for safeties sake!

I hope your new EPROM reader can handle the 2716s, if not if it can read
2732s then you will get the data twice and you can split off the high
and low sections.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On 2019/11/15 5:26 a.m., John-Del wrote:
On Friday, November 15, 2019 at 4:45:16 AM UTC-5, Cursitor Doom wrote:
On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:


If so, the first thing to get checked is the electros. I pull every one
and test them for value, ESR, and dielectric absorption. Testing ESR in
circuit on many modern circuit boards is a waste of time.

Why so?


Too many circuits these days use a small value SMD multi layer chip capacitor bypassing an electrolytic. These chip caps have ESR figures as low or lower than most electrolytics you're likely to run across despite being small value caps.


Except this machine is from 1982 (paper tape readers, etc.) - so any
electros are primary smoothing ones for Vcc.

http://cncmanual.com/download/1647/

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On Fri, 15 Nov 2019 08:42:37 -0800, John Robertson
wrote:

On 2019/11/15 5:26 a.m., John-Del wrote:
On Friday, November 15, 2019 at 4:45:16 AM UTC-5, Cursitor Doom wrote:
On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:


If so, the first thing to get checked is the electros. I pull every one
and test them for value, ESR, and dielectric absorption. Testing ESR in
circuit on many modern circuit boards is a waste of time.

Why so?


Too many circuits these days use a small value SMD multi layer chip capacitor bypassing an electrolytic. These chip caps have ESR figures as low or lower than most electrolytics you're likely to run across despite being small value caps.


Except this machine is from 1982 (paper tape readers, etc.) - so any
electros are primary smoothing ones for Vcc.

http://cncmanual.com/download/1647/

John :-#)#
Some Grass Valley products from the early 80s had electrolytics that
would open but the surrounding circuitry would cause an ESR meter to
read very low ESR. Once the electrolytic was pulled, it would test
bad.

The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric

On 2019/11/15 12:01 p.m., wrote:
On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric


I would HIGHLY recommend that you keep the original EPROMs and get some
good 2716s to burn and a few spares...

Please do not erase your originals!

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On Fri, 15 Nov 2019 12:38:19 -0800, John Robertson
wrote:

On 2019/11/15 12:01 p.m., wrote:
On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric


I would HIGHLY recommend that you keep the original EPROMs and get some
good 2716s to burn and a few spares...

Please do not erase your originals!

John :-#)#
I will NOT be erasing the originals. They are, as near as I can tell,
not available from any soyrce. I have looked for a long time on eBay
in the hope that someone scrapping a machine will have some. But the
machines, while similar, are never the same. I'm even afriad to copy
them. That's why I am going to practice on some others first.
Eric

On 2019/11/15 12:47 p.m., wrote:
On Fri, 15 Nov 2019 12:38:19 -0800, John Robertson
wrote:

On 2019/11/15 12:01 p.m., wrote:
On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric


I would HIGHLY recommend that you keep the original EPROMs and get some
good 2716s to burn and a few spares...

Please do not erase your originals!

John :-#)#
I will NOT be erasing the originals. They are, as near as I can tell,
not available from any soyrce. I have looked for a long time on eBay
in the hope that someone scrapping a machine will have some. But the
machines, while similar, are never the same. I'm even afriad to copy
them. That's why I am going to practice on some others first.
Eric


Reading is pretty safe, however I would recommend you contact MCUmall
and make sure that the READ process for pin 21 is done at 5VDC and not
at the programming voltage which is 21VDC. You can verify this with a
voltmeter by simply not having any chip in the socket and then do a read
while monitoring socket pin 21 (ad common at pin 12) to make sure the
voltage is 5VDC. It would not hurt to verify that pin 24, again relative
to pin 12 - is also 5VDC. Lastly, for the paranoid folks, I would also
check pin 20 and 18 to make sure they are never higher than 5VDC.

I am not saying the MCUmall programmer is bad, I'm just pointing out how
I would check any programmer that I am trusting irreplaceable EPROMs to!

If you have a scope so much the better to test the programmer READ
voltages at the various pins!

As you say you only have the one set of EPROMs and your equipment would
be worthless if any are damaged by the programmer!

Does this machine have an 8-bit CPU such as Z80, 68XX, 6502, etc? If
someone lives near you and has a Fluke 9010 with the appropriate pod
then they could extract the data from the EPROMs at no risk to them.
They would also need an RS-232 port on the Fluke to grab the data... I
can do this in my shop, but I suspect we are not very close - I'm in
Vancouver (Burnaby, but no one knows that city), Canada area...

John

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On Fri, 15 Nov 2019 13:48:51 -0800, John Robertson
wrote:

On 2019/11/15 12:47 p.m., wrote:
On Fri, 15 Nov 2019 12:38:19 -0800, John Robertson
wrote:

On 2019/11/15 12:01 p.m., wrote:
On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric


I would HIGHLY recommend that you keep the original EPROMs and get some
good 2716s to burn and a few spares...

Please do not erase your originals!

John :-#)#
I will NOT be erasing the originals. They are, as near as I can tell,
not available from any soyrce. I have looked for a long time on eBay
in the hope that someone scrapping a machine will have some. But the
machines, while similar, are never the same. I'm even afriad to copy
them. That's why I am going to practice on some others first.
Eric


Reading is pretty safe, however I would recommend you contact MCUmall
and make sure that the READ process for pin 21 is done at 5VDC and not
at the programming voltage which is 21VDC. You can verify this with a
voltmeter by simply not having any chip in the socket and then do a read
while monitoring socket pin 21 (ad common at pin 12) to make sure the
voltage is 5VDC. It would not hurt to verify that pin 24, again relative
to pin 12 - is also 5VDC. Lastly, for the paranoid folks, I would also
check pin 20 and 18 to make sure they are never higher than 5VDC.

I am not saying the MCUmall programmer is bad, I'm just pointing out how
I would check any programmer that I am trusting irreplaceable EPROMs to!

If you have a scope so much the better to test the programmer READ
voltages at the various pins!

As you say you only have the one set of EPROMs and your equipment would
be worthless if any are damaged by the programmer!

Does this machine have an 8-bit CPU such as Z80, 68XX, 6502, etc? If
someone lives near you and has a Fluke 9010 with the appropriate pod
then they could extract the data from the EPROMs at no risk to them.
They would also need an RS-232 port on the Fluke to grab the data... I
can do this in my shop, but I suspect we are not very close - I'm in
Vancouver (Burnaby, but no one knows that city), Canada area...

John
It's a Fanuc control and as far as I know the control is completely
Fanuc. I don't know anyone who has s Fluke 9010 and even though I know
where Burnaby is it is still a bit of a drive from the south end of
Whidbey Island.
I do have other 2516 EPROMs that are useless to me that I am going
to use to test the reader/programmer. The tech support guy did say
that 2516 devices may not program properly but that they can be read
just fine. Nevertheless I will take your advice. I can use my TEK 465B
scope to check the voltages.
And I read either here or in an email from the tech support folks
that the TI 2516 devices are the same as the 2716 devices and I know
that at least one EPROM is a TI 2516.
There is a mix of devices because it seems that at least two EPROMs
are common to almost every board from Miyano lathes and the other 4 on
the one board are the ones I need to copy.
So as I buy old boards I get, now and then, copies of the two
common types. So these will be tested first along with some other 2516
devices I have from another Fanuc control.
I really appreciate all the advice I get here and especially the
EPROM advice I am getting recently. It really makes me feel better
about repairing this machine.
Speaking of this lathe, I know people who would say just replace
the machine or at least the control. But I have done a complete
control replacement before and it is not trivial. And Fanuc controls
are usually very robust. It is just this one board that is giving me
problems and I can't see how the machine itself could be damaging this
particular board.
I could just replace the machine completely but this is very
expensive and this particular machine is just not getting enough work
at this time to justify at least 60 grand to replace it.
The lathe itself is, the mechanics and the servos, are in great
shape. I can hold .0001" without any problems. All day. Even though
the top spindle speed is only 5000 RPM most of the work I do can't be
done at higher RPM because of the diameter and material of the work.
Eric

On 2019/11/15 3:57 p.m., wrote:
On Fri, 15 Nov 2019 13:48:51 -0800, John Robertson
wrote:

On 2019/11/15 12:47 p.m., wrote:
On Fri, 15 Nov 2019 12:38:19 -0800, John Robertson
wrote:

On 2019/11/15 12:01 p.m., wrote:
On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson
wrote:

On 2019/11/15 10:56 a.m., Ron D. wrote:
The EProms can cause issues when they age.

From my days of programming the 2716's. My programmer was semi-manual and it was really sensitive to the the programming voltage.

An EEprom may not have been erased completely.

Do inspect the board for bad solder joints.

Freeze spray can sometimes help make equipment fail or work. On a non-powered board, it can help highlight a bad solder joint.


My Xeltek 610P programmer has a feature where it will test EPROMs at +/-
10% of the voltage to help weed out iffy burns or EPROMs.

Recently I had some EPROMs I was verifying and they failed the
over-voltage test - so I reprogrammed them (not erased, just hit them
with the programmer burn process) and then they tested just fine. I
assume I recharged the gates so all was then well.

John :-#)#
I will need to erase the EPROMs before they get new programs. My
wife has a UV light source she uses for curing some sort of fingernail
coating for artificial nails. I'm hoping it will work OK.
The programmer I am buying is the MCUmall Electronics model GQ-4x4.
I called them and they said programmer software verifies the info
downloaded from the EPROM and then once again verifies the uploaded
info.
Eric


I would HIGHLY recommend that you keep the original EPROMs and get some
good 2716s to burn and a few spares...

Please do not erase your originals!

John :-#)#
I will NOT be erasing the originals. They are, as near as I can tell,
not available from any soyrce. I have looked for a long time on eBay
in the hope that someone scrapping a machine will have some. But the
machines, while similar, are never the same. I'm even afriad to copy
them. That's why I am going to practice on some others first.
Eric


Reading is pretty safe, however I would recommend you contact MCUmall
and make sure that the READ process for pin 21 is done at 5VDC and not
at the programming voltage which is 21VDC. You can verify this with a
voltmeter by simply not having any chip in the socket and then do a read
while monitoring socket pin 21 (ad common at pin 12) to make sure the
voltage is 5VDC. It would not hurt to verify that pin 24, again relative
to pin 12 - is also 5VDC. Lastly, for the paranoid folks, I would also
check pin 20 and 18 to make sure they are never higher than 5VDC.

I am not saying the MCUmall programmer is bad, I'm just pointing out how
I would check any programmer that I am trusting irreplaceable EPROMs to!

If you have a scope so much the better to test the programmer READ
voltages at the various pins!

As you say you only have the one set of EPROMs and your equipment would
be worthless if any are damaged by the programmer!

Does this machine have an 8-bit CPU such as Z80, 68XX, 6502, etc? If
someone lives near you and has a Fluke 9010 with the appropriate pod
then they could extract the data from the EPROMs at no risk to them.
They would also need an RS-232 port on the Fluke to grab the data... I
can do this in my shop, but I suspect we are not very close - I'm in
Vancouver (Burnaby, but no one knows that city), Canada area...

John
It's a Fanuc control and as far as I know the control is completely
Fanuc. I don't know anyone who has s Fluke 9010 and even though I know
where Burnaby is it is still a bit of a drive from the south end of
Whidbey Island.
I do have other 2516 EPROMs that are useless to me that I am going
to use to test the reader/programmer. The tech support guy did say
that 2516 devices may not program properly but that they can be read
just fine. Nevertheless I will take your advice. I can use my TEK 465B
scope to check the voltages.
And I read either here or in an email from the tech support folks
that the TI 2516 devices are the same as the 2716 devices and I know
that at least one EPROM is a TI 2516.
There is a mix of devices because it seems that at least two EPROMs
are common to almost every board from Miyano lathes and the other 4 on
the one board are the ones I need to copy.
So as I buy old boards I get, now and then, copies of the two
common types. So these will be tested first along with some other 2516
devices I have from another Fanuc control.
I really appreciate all the advice I get here and especially the
EPROM advice I am getting recently. It really makes me feel better
about repairing this machine.
Speaking of this lathe, I know people who would say just replace
the machine or at least the control. But I have done a complete
control replacement before and it is not trivial. And Fanuc controls
are usually very robust. It is just this one board that is giving me
problems and I can't see how the machine itself could be damaging this
particular board.
I could just replace the machine completely but this is very
expensive and this particular machine is just not getting enough work
at this time to justify at least 60 grand to replace it.
The lathe itself is, the mechanics and the servos, are in great
shape. I can hold .0001" without any problems. All day. Even though
the top spindle speed is only 5000 RPM most of the work I do can't be
done at higher RPM because of the diameter and material of the work.
Eric


Whidbey Island is just a day trip to Vancouver/Burnaby. I'd be happy to
archive your EPROMs and burn you up a set of spares if you can't sort it
out...

I think you are neighbour to my friend the ex-basketball player who
loves pinball, if you know who I am speaking of, tell him I said "Hi!".

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

On Friday, November 15, 2019 at 5:30:14 AM UTC-8, John-Del wrote:
On Thursday, November 14, 2019 at 11:14:21 PM UTC-5, Ralph Mowery wrote:
In article ,
says...
eport if the normal operation is restored when heated.

If so, the first thing to get checked is the electros. I pull every one and test them for value, ESR, and dielectric absorption. Testing ESR in circuit on many modern circuit boards is a waste of time.




Once pulled, you might as well not test them, just replace them.

You may want to test the new ones before you put them in.


If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with..

Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data. Sometimes you just have to replace a board.

'lytic caps go bad eventually. After removing the caps for testing you've already run the risk of damaging the board. Why put the old ones back? In broadcast gear small value caps are the most common failures. I've replaced thousands of 100uF 25 V caps. Unit price 32 cents, 1000 for $83. Buy in bulk and replace in bulk. It costs less than testing and re-installing.

G²

In article ,
says...

'lytic caps go bad eventually. After removing the caps for testing you've already run the risk of damaging the board. Why put the old ones back? In broadcast gear small value caps are the most common failures. I've replaced thousands of 100uF 25 V caps. Unit price 32 cents, 1000 for $83. Buy in bulk and replace in bulk. It costs
less than testing and re-installing.

G


Right, at the small cost of the capacitors, it is foolish to put backin
an old one even if the board may have other problems and not used.

Now if it was a $ 10 or even maybe a $ 5 part it may be worth putting
the old part back on.

At the rate capacitors fail, the one that tested good may go bad much
sooner than a new one. Then you have to do it all over again.

It takes often takes more labor time and effort to test than to just put
in a new one.


Like where I work, a man from the factory came in to repair a 480 volt 3
phase 200 HP motor speed control. He found 2 bad dioides that were
rated at something like 200 amps. I asked him to replace the 3 rd one.
He told me those things cost arond $ 200 each. I told him that with 2
bad it may have weakened the 3 rd one. With the machinery costing the
company over $ 1000 per hour for down time, and the cost of getting him
back in the plant, I am willing to pay $ 200 for insurance and piece of
mind. That old diode may pop in a day or 10 years, but I know that I
have done my best to make sure the machine keeps on running for minimal
extra cost.

On Saturday, November 16, 2019 at 5:05:47 AM UTC-5, wrote:

If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with.

Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data. Sometimes you just have to replace a board.

'lytic caps go bad eventually. After removing the caps for testing you've already run the risk of damaging the board.



Anyone who would ruin a board by removing a cap isn't a professional and shouldn't be playing with it. There is ZERO chance of damaging even a multi-layer board.



Why put the old ones back? In broadcast gear small value caps are the most common failures. I've replaced thousands of 100uF 25 V caps. Unit price 32 cents, 1000 for $83. Buy in bulk and replace in bulk. It costs less than testing and re-installing.



You actually quoted my reason (thanks for not snipping it) but either didn't read it or didn't understand it. So I've copied and pasted my previously posted reason below:

"If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with."

"Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data.. Sometimes you just have to replace a board."


So if I have to replace a board that caps won't fix, why go through the trouble of recapping it? On low to mid percentage shots like these one-off industrial controls, the plan is five stages:

1)I troubleshoot and repair the board first. If it's not repairable, I go to step 5. If I get the board repaired, I go to step 2.

2)recap it

3)Clean and deflux the board, and inspect under a bright light and loop. Reflow any questionable solder and reflow all the solder on edge connectors, transformers, and high heat generating components.

4)Deflux again and spray with conformal coating if the board originally was built with it.

5)Get paid for my time.

On Saturday, November 16, 2019 at 11:09:21 AM UTC-5, Ralph Mowery wrote:
In article ,
says...

'lytic caps go bad eventually. After removing the caps for testing you've already run the risk of damaging the board. Why put the old ones back? In broadcast gear small value caps are the most common failures. I've replaced thousands of 100uF 25 V caps. Unit price 32 cents, 1000 for $83. Buy in bulk and replace in bulk. It costs
less than testing and re-installing.

G


Right, at the small cost of the capacitors, it is foolish to put backin
an old one even if the board may have other problems and not used.


I've read that sentence like 5 times and all I can say is that you wouldn't be working for me..

Honestly, sometimes I wonder if people just post because they want to say *something*.

On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:

Anyone who would ruin a board by removing a cap isn't a professional and
shouldn't be playing with it. There is ZERO chance of damaging even a
multi-layer board.

There is when *I'm* around! Here's how I got an inaccessible cap out of
this network analyser a couple of days ago: https://postimg.cc/bZYGSvnr

But as you will probably gather, I'm no professional. :-D




--
This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:

So if I have to replace a board that caps won't fix, why go through the
trouble of recapping it?

I'm worried about cheap Chinese crap getting into the supply chain and
that's why I'd rather leave things be. I might end up replacing a
perfectly serviceable 40 year old cap made by a prime manufacturer with
something nasty from China that's going to go *phut* long before the
original one would have.



--
This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

On Saturday, November 16, 2019 at 7:57:21 PM UTC-5, Cursitor Doom wrote:
On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:

So if I have to replace a board that caps won't fix, why go through the
trouble of recapping it?

I'm worried about cheap Chinese crap getting into the supply chain and
that's why I'd rather leave things be. I might end up replacing a
perfectly serviceable 40 year old cap made by a prime manufacturer with
something nasty from China that's going to go *phut* long before the
original one would have.


It's a good plan to avoid knock-off parts of any type. Many of old timers have seen counterfeit parts going back 40 years or more.

You just need to be careful about where you source your parts. Here in the states, I use DigiKey mostly. I can buy cheaper caps but I prefer to buy from a trusted supplier. Plus, companies like DigiKey and Mouser have a huge selection of caps. So one can select not only value, voltage rating, and lead configuration, but also have the option of selecting manufacturer, ESR, and lifetime hours ratings.

I generally only buy Panasonic capacitors because I've grown to trust them. In industrial controls where they are all on the time in a wide variety of temperature extremes, I don't want a cap with a 1000 or 2000 hour rating.

I also know that with DigiKey and Mouser, I'll get a genuine Panasonic or Nichicon capacitor if I order one. They cost more than I can get them elsewhere, but I'd rather pay more to know I'm not getting a knock-off.

I also know that a new Panasonic cap (like the EEU-TA series) *will* last longer than the original ten year old capacitor with many thousands of hours on it. Even a top quality capacitor is still on borrowed time after 40 years.

On Sun, 17 Nov 2019 07:52:26 -0800, John-Del wrote:

It's a good plan to avoid knock-off parts of any type. Many of old
timers have seen counterfeit parts going back 40 years or more.

Where did those fakes come from 40 years ago?? I'm guessing certainly not
from China. China joined the game *much* later AFAIK.

You just need to be careful about where you source your parts. Here in
the states, I use DigiKey mostly. I can buy cheaper caps but I prefer
to buy from a trusted supplier. Plus, companies like DigiKey and Mouser
have a huge selection of caps. So one can select not only value,
voltage rating, and lead configuration, but also have the option of
selecting manufacturer, ESR, and lifetime hours ratings.

It's kind of baffling when one first sees the range of choice available
from those two suppliers, though. I find it takes me *so* much longer to
find the part I want than when I was with Farnell/CPC which had a much
more limited range. Sometimes you can have too much choice and it becomes
a PITA to sort through it all, even with all those filters. Perhaps I'll
feel differently once I eventually get used to it.

I generally only buy Panasonic capacitors because I've grown to trust
them.

Amen to that. Same here!



--
This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

On Sunday, November 17, 2019 at 12:34:45 PM UTC-5, Cursitor Doom wrote:
On Sun, 17 Nov 2019 07:52:26 -0800, John-Del wrote:

It's a good plan to avoid knock-off parts of any type. Many of old
timers have seen counterfeit parts going back 40 years or more.

Where did those fakes come from 40 years ago?? I'm guessing certainly not
from China. China joined the game *much* later AFAIK.


Japan mostly, but that is supposition on my part. I believe some of those fakes were simply relabeled parts and not necessarily purposely built as counterfeits. Back in the CRT TV days, we'd buy horizontal/line output transistors a hundred at a shot (like the Toshiba 2SC1172B or Sanyo 1308K). Then we started getting counterfeits that would last minutes to days, then blow. We used to buy Sony SG613s in bulk and never had a problem. Suddenly the next shipment would blow up on plug in.

We also saw TONS of Motorola and Toshiba audio outputs for stereo equipment that were relabeled. Vertical ICs, SMPS regulators etc.. There was virtually no category untouched. I even remember the counterfeit Sony "jungle" ICs that would work for a few days, weeks, or months, then cause shutdowns or other odd symptoms. The Sony jungle ICs were complicated devices and these were either line rejects or purposely built to counterfeit. I don't really know nor does it really matter at my end. All I know is that they caused costly callbacks.

My guess is that a lot of the early counterfeits were just the lower power/current/voltage versions of the series that were cleaned and reprinted.

Cursitor Doom wrote:

---------------------

John-Del wrote:

It's a good plan to avoid knock-off parts of any type. Many of old
timers have seen counterfeit parts going back 40 years or more.

Where did those fakes come from 40 years ago?? I'm guessing certainly not
from China. China joined the game *much* later AFAIK.



** Back in 1980, on open sale in Australia were counterfeit Motorola power transistors. Thousands of them, either included in amplifier kits or across the counter.

The devices were branded "TIC" for " Transistor Instrument Company" operating from, Florida. They did not in fact manufacture anything but had a catalogue with hundreds of types.

What TIC did was buy up surplus TO3 stock and remove the original labelling - then re-ink the parts according to your order. So a 10 cent item became worth several dollars each. Just about the only similarity was the TO3 pak.

The ones I saw and tried to use were Motorola numbers MJ1003 & MJ15004. The exact same scam was done by fake wholesalers in places like Hong Kong.

Another fake wholesaler in the same state was called "Aero" and dealt mostly in relabelled and used vacuum tubes - again with a large catalogue.

On offer were "new" transmitting tubes from them for hundreds of dollars a piece that had already seen thousands of hours of use. Or tubes from famous US maker Sylvania that were re-labelled stock from places like East Germany or Yugoslavia - for double the going price.

When surplus stocks ran out, shiny new fakes were created in India or China that only resembled the real things in appearance.

Manufacturers well knew to keep away, so sales normally only went to various retail operations and for spare parts.



...... Phil

On 2019/11/17 10:10 a.m., John-Del wrote:
On Sunday, November 17, 2019 at 12:34:45 PM UTC-5, Cursitor Doom wrote:
On Sun, 17 Nov 2019 07:52:26 -0800, John-Del wrote:

It's a good plan to avoid knock-off parts of any type. Many of old
timers have seen counterfeit parts going back 40 years or more.

Where did those fakes come from 40 years ago?? I'm guessing certainly not
from China. China joined the game *much* later AFAIK.


Japan mostly, but that is supposition on my part. I believe some of those fakes were simply relabeled parts and not necessarily purposely built as counterfeits. Back in the CRT TV days, we'd buy horizontal/line output transistors a hundred at a shot (like the Toshiba 2SC1172B or Sanyo 1308K). Then we started getting counterfeits that would last minutes to days, then blow. We used to buy Sony SG613s in bulk and never had a problem. Suddenly the next shipment would blow up on plug in.

We also saw TONS of Motorola and Toshiba audio outputs for stereo equipment that were relabeled. Vertical ICs, SMPS regulators etc.. There was virtually no category untouched. I even remember the counterfeit Sony "jungle" ICs that would work for a few days, weeks, or months, then cause shutdowns or other odd symptoms. The Sony jungle ICs were complicated devices and these were either line rejects or purposely built to counterfeit. I don't really know nor does it really matter at my end. All I know is that they caused costly callbacks.

My guess is that a lot of the early counterfeits were just the lower power/current/voltage versions of the series that were cleaned and reprinted.


Japan was a 'problem' back in the 50s and 60s - a friend of mine who
lived in Japan in the 60s told me how they literally copied slot
machines - they would buy one US slot, take it apart, and build exact
replicas...

But, then again, the US was a problem back in the 1700 and 1800s!

Copyright laws did not exist in the US way back when and lots of
publications that were protected in Europe were freely reprinted on the
other side of the pond..

https://www.varsitytutors.com/earlya...-copyright-law

Currency:

https://www.history.org/Foundation/j...ounterfeit.cfm

Roman times:

https://coinweek.com/ancient-coins/b...ir-fake-coins/

Counterfeit stuff has always been around, that is why "bricks & mortar"
places like Digikey, Mouser, Element 14, are trusted - unlike parts you
buy off eBay or Amazon. Lots of Russian renumbered parts there...

John :-#)#

On Sun, 17 Nov 2019 10:10:00 -0800, John-Del wrote:

Japan mostly, but that is supposition on my part. I believe some of
those fakes were simply relabeled parts and not necessarily purposely
built as counterfeits. Back in the CRT TV days, we'd buy
horizontal/line output transistors a hundred at a shot (like the Toshiba
2SC1172B or Sanyo 1308K). Then we started getting counterfeits that
would last minutes to days, then blow. We used to buy Sony SG613s in
bulk and never had a problem. Suddenly the next shipment would blow up
on plug in.


I had no idea it was so universal. I mean, until recently I thought the
problem was confined pretty much solely to voltage regulators, but
clearly it goes way beyond that. I find it all (the 'infection' of the
supply chain) deeply concerning.



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Cursitor Doom wrote:

----------------------


I had no idea it was so universal. I mean, until recently I thought the
problem was confined pretty much solely to voltage regulators, but
clearly it goes way beyond that. I find it all (the 'infection' of the
supply chain) deeply concerning.


** The second time ( a few years later) I found myself with fake MJ15003/4 I made an effort to track down the source.

My supplier assured me it was "Motorola Australia" in Sydney - so I rang them and explained the situation. The sales guy checked the company database and found NO sales of those types had been made to the supplier in several years.

Further investigation tracked the importing to a dealer in Melbourne who had offered them to likely customers all over the place. The stock same from a fake warehouse in Hong Kong.

The official line from Motorola here was that one should ONLY deal with authorised suppliers of the brand who offered traceability.

One such dealer told me the problem was rife, claiming hardly a day went by when nobody rang offering to sell them fake semis. The most common back then were memory chips, all nicely packed in bulk containers and all relabelled as to the rated speed.



...... Phil

On 11/14/2019 6:01 PM, wrote:
On Thu, 14 Nov 2019 13:03:28 -0800, John Robertson
wrote:

On 2019/11/14 12:20 p.m., wrote:
One of my CNC machines has a circuit board that has failed 3 times
now. The control is a FANUC 3T. It is an older control so failing
boards don't surprise me. But it is just the one board. This board has
many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and
one electrolytic capacitor. I have checked this cap on two boards with
my meter and the cap has the stated value and is not shorted. But I
don't have a way to check ESR.
The failure mode for all the boards is the same. First the turret
on this lathe will occasionally index in the wrong direction. After
the machine is powered up for a while it will then start to index
properly. I can control the turret rotation from a program but when
the board starts to fail it will only index in one direction.
Furthermore, then turret should always rotate in the direction that
is the shortest to the next tool called up, but when the board starts
going bad the turret still only indexes in one direction.
Unfortunately this is the wrong direction.
After this failure other things start going wrong, like the speed
control. Changing the boards has always fixed the problem. Note that
when I change the boards I have to swap all the EPROMs so that the
programming for the machine operation will be the same.
Since all the boards seem to fail the same way I was wondering if
somehow a failing cap could cause this failure. Even though the cap
value reads fine with my VOM, that does not measure ESR.
In any case I'm gonna order some caps and see if anything changes
but I would like to know if it is probably gonna be a waste of time.
Thanks,
Eric


I'd say it is unlikely the capacitor is the problem - normally these are
used to smooth the Vcc to the chips. You say there are custom chips on
the board, so depending on if you can get schematics or not then you may
be looking at the rest of the circuits.

Regular electrolytic caps are rarely used for critical timing, rather
they would use a tantalum cap if the value was important.

If you want to check the ESR then Bob Parker's Blue ESR meter kit is not
a bad way to go...available here (flippers.com - shameless plug!) and
there...

However I don't think the cap is responsible for your problems.

Have you tried simply reseating the chips and connectors to the PCB and
any readouts, sensors, etc. in case it may be that simply reseating
plugs fixes the problem?

If the problem is only apparent after the machine has been on a while
have you checked the temperature of the logic? Chips don't like being
more than 50C by and large, and the cooler they run the better. A heat
gun and some cold spray may help find the sensitive IC as you say the
problem goes away when the system is warm.

John :-#)#


Greetings John,
Actually the machine starts to work after it has warmed up for a
while.

If this is a consistent response, you may be able to locate the problem
by heating/cooling the board. The easiest way is to have the board
warmed and working. Buy yourself a can or two of 'Freeze Mist' spray
half the board to cool it down, while checking operation. If it still
works, let it warm up completely so you don't confuse the issue. Now
cool of the other half of the PCB and check operation. If it
malfunctions, you know which end to continue troubleshooting. Warm it up
until proper operation, then start cooling individual parts on the bad
1/2 of the pcb, one at a time until the problem occurs. You can often
isolate the problem part this way.

Or you can do just the opposite, cool the pcb in the fridge, then use
isolated heat until the machine works. It is harder to isolate the heat
than to cool an individual part. So, I recommend the first procedure.
If you decide to use heat on the pcb, use a hair dryer, not a heat gun.

Mikek

Freeze Mist, pick the best price with shipping.
https://www.google.com/search?client...&q=freeze+mist
Skip the CRC automotive product, I suspect it has other chemicals in it.

On 11/16/19 10:09 AM, Ralph Mowery wrote:
Right, at the small cost of the capacitors, it is foolish to put back
in an old one even if the board may have other problems and not used.

Now if it was a $ 10 or even maybe a $ 5 part it may be worth putting
the old part back on.

Not even with $5-10 parts.
My time is worth more than that.

At the rate capacitors fail, the one that tested good may go bad much
sooner than a new one. Then you have to do it all over again.

It takes often takes more labor time and effort to test than to just
put in a new one.

Exactly, and then you KNOW they aren't the problem.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

On 11/17/19 9:52 AM, John-Del wrote:
It's a good plan to avoid knock-off parts of any type.

Apparently some people still haven't learned, "Pay ****,
get ****."


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

Fox's Mercantile wrote:

-------------------------
John-Del wrote:
It's a good plan to avoid knock-off parts of any type.

Apparently some people still haven't learned, "Pay ****,
get ****."


** Those who have not learned are dealers in components.

Counterfeiters know their best market and approach firms acting as wholesalers for many brands with "bulk surplus stock" of the same brand at an appealing price. The items then get sold as regular stock the normal rate.

Sometimes, fake items are put into stock by rogue staffers who take away the genuine stuff and sell it off elsewhere. Happened to Farnell a few years back with On Semi power transistors.

Best way to hide a fake semi is to make them look good and sell at standard going prices.


..... Phil

On Sunday, November 17, 2019 at 9:01:31 PM UTC-5, Phil Allison wrote:


Best way to hide a fake semi is to make them look good and sell at standard going prices.


.... Phil

They do with with DLP lamps. OEM bulbs over here generally cost $80 U.S. give or take. People started buying ebay and Amazon lamps for a third of the cost of OEM and finding out they were either crapping out immediately or within a few months. They generally are not as bright as well. People started avoiding the cheap lamps.

A few sellers have been selling counterfeit Philips bulbs at prices just below what Philips lamps sell for - seems like a great deal on Philips brand bulbs but it's the same old crappy lamp at a lot more money.