Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl

On Jun 11, 5:26*pm, Karl Townsend
wrote:
Plugged in the electric fencer and the meter reads “short” but it
still *shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. *A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl

You could make a small coil and connect it to a galvanometer:

http://www.hometrainingtools.com/gal.../p/EL-GALVAN1/

and pass one of the HV fence wires through it. If the resistance it
too low you might get an idea of current flow. Good for a relative
measurement (just not quantative).

On Tue, 11 Jun 2013 17:26:05 -0500, Karl Townsend
wrote:

Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl

If it is a DC pulse, like the device my father had many years ago,
than a multi-meter with a series resister will measure voltage with
the caveat that as you are measuring between the fence and ground your
ground connection will have a large effect on the voltage that the
meter reads.

--
Cheers,

John B.

"Karl Townsend" wrote in message
...
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl

Karl Townsend wrote:

Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. DonÂ’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all thatÂ’s needed. or time to buy
another unit? ($250)

I'd add a neon lamp and a high-value series resistor, maybe
a string of a couple dozen 100 K resistors. You need a bunch
in series so they don't arc over. As long as the lamp is
blinking, it is still working.

Jon

On 6/11/2013 6:26 PM, Karl Townsend wrote:
Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl



Is that to keep stray cats away? (Word must have gotten out among the
cat community.)

In article , elson@pico-
systems.com says...
Karl Townsend wrote:

Plugged in the electric fencer and the meter reads ?short? but it
still shocks the **** out of you. Don?t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that?s needed. or time to buy
another unit? ($250)

Karl,

Most fence chargers are prtetty simple, I have schematics of a few
designs. What brand is yours?

Units with a meter typically connect the meter to a 1 or 2 turn
secondary on the output transformer. Depending on the design of your
charger, the meter curcuit can be as simple as a diode and a meter
movement or somewhat more complex.

It would be well worth your while to open the charger up and take a look
at what you have. It could be a bad meter movement, a bad diode or even
a dead insect in the meter movement blocking motion. Supposedly, the
movement is sealed os a bug can't get in, but as you probably know they
can get into surprising places.

WayneJ

On Wed, 12 Jun 2013 00:48:41 -0400, Tom Gardner Mars@Tacks wrote:

On 6/11/2013 6:26 PM, Karl Townsend wrote:
Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl



Is that to keep stray cats away? (Word must have gotten out among the
cat community.)

This is for my very large rats with hooves. (deer) Takes a SERIOUS pop
to tell them not to come back.

I also use it around the sweet corn patch for the masked bandits
(racoons)

Karl

On Tue, 11 Jun 2013 21:56:33 -0700, WayneJ wrote:

In article , elson@pico-
systems.com says...
Karl Townsend wrote:

Plugged in the electric fencer and the meter reads ?short? but it
still shocks the **** out of you. Don?t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that?s needed. or time to buy
another unit? ($250)

Karl,

Most fence chargers are prtetty simple, I have schematics of a few
designs. What brand is yours?

Units with a meter typically connect the meter to a 1 or 2 turn
secondary on the output transformer. Depending on the design of your
charger, the meter curcuit can be as simple as a diode and a meter
movement or somewhat more complex.

It would be well worth your while to open the charger up and take a look
at what you have. It could be a bad meter movement, a bad diode or even
a dead insect in the meter movement blocking motion. Supposedly, the
movement is sealed os a bug can't get in, but as you probably know they
can get into surprising places.

WayneJ

Its a Parmak precision brand. Made in USA - KC MO

A proper repair would be huge. I did find this on the web
http://www.dickselectricfencerrepair.com/ But likely, the repair will
be about the same as a new one. Mine is a 6 Joule 7K volt rated unit.
Now, I see you can get 10 Joule 12K volt units. Maybe its time to
upgrade.



For years, I've moved a metal post close to the wire to make sure it
pops a good arc. I'm thinking, make this accurate for a measurment.
I'll just set up a stop with a threaded bolt, probably use 3/4x10 so
each turn is 0.100". I know the fencer pops 1/4 to 3/8 when in top
form, if it won't pop more than about 1/8 its time to find the
problem.

Karl Townsend wrote:

Its a Parmak precision brand. Made in USA - KC MO

A proper repair would be huge. I did find this on the web
http://www.dickselectricfencerrepair.com/ But likely, the repair will
be about the same as a new one. Mine is a 6 Joule 7K volt rated unit.
Now, I see you can get 10 Joule 12K volt units. Maybe its time to
upgrade.


Make sure the insulators are clean. They will bleed off a lot of the
energy if they are dirty. It goes without saying, but turn it off
before you do the inspection. ;-)


See if you can find an old Pomona or B&K TV HV probe with a built in
meter. You'll need to add a couple diodes to rectify the AC, but then
it's a simple matter of clipping the lead to ground, and touching the
probe to the wire.


Here is an example of a B&K on Ebay:
http://www.ebay.com/itm/4d0d4bb550


Fluke, Heathkit & others made probes to use with a 10 Megohm input
impedance meter, but they cost as much, or more than the probe type..


http://www.ebay.com/sch/i.html?_trksid=p3984.m570.l1313.TR2.TRC1.A0&_nkw=h v+probe&_sacat=0&_from=R40

On 6/11/2013 3:26 PM, Karl Townsend wrote:
Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl

Go to your local farm store and buy a fence tester. You need one anyway
to find breaks in the fence. They are a series of high value resistors
with neon bulbs across the resistors.

Use the tester when you need to, or just hook it permanently to the charger.

Paul

Jon Elson wrote:

Karl Townsend wrote:

Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. DonÂ’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all thatÂ’s needed. or time to buy
another unit? ($250)

I'd add a neon lamp and a high-value series resistor, maybe
a string of a couple dozen 100 K resistors. You need a bunch
in series so they don't arc over. As long as the lamp is
blinking, it is still working.


Make sure to clean the body oil off them, and that you don't exceed
the rated voltage for each resistor.

Go to your local farm store and buy a fence tester. You need one anyway
to find breaks in the fence. They are a series of high value resistors
with neon bulbs across the resistors.

Use the tester when you need to, or just hook it permanently to the charger.

Paul
BINGO

Didn't know such a thing existed, I'll order one.

Karl

In article ,
says...

On Tue, 11 Jun 2013 21:56:33 -0700, WayneJ wrote:

Karl,

Most fence chargers are prtetty simple, I have schematics of a few
designs. What brand is yours?

Units with a meter typically connect the meter to a 1 or 2 turn
secondary on the output transformer. Depending on the design of your
charger, the meter curcuit can be as simple as a diode and a meter
movement or somewhat more complex.

It would be well worth your while to open the charger up and take a look
at what you have. It could be a bad meter movement, a bad diode or even
a dead insect in the meter movement blocking motion. Supposedly, the
movement is sealed os a bug can't get in, but as you probably know they
can get into surprising places.

WayneJ

Its a Parmak precision brand. Made in USA - KC MO

A proper repair would be huge. I did find this on the web
http://www.dickselectricfencerrepair.com/ But likely, the repair will
be about the same as a new one. Mine is a 6 Joule 7K volt rated unit.
Now, I see you can get 10 Joule 12K volt units. Maybe its time to
upgrade.



For years, I've moved a metal post close to the wire to make sure it
pops a good arc. I'm thinking, make this accurate for a measurment.
I'll just set up a stop with a threaded bolt, probably use 3/4x10 so
each turn is 0.100". I know the fencer pops 1/4 to 3/8 when in top
form, if it won't pop more than about 1/8 its time to find the
problem.

Yeah, a 6 Joule unit will get your attention if it hits you!

I have a partial schematic for a smaller Parmak. Parmak uses a somewhat
more complicated metering circuit than some. One turn of wire around the
outside of the output transformer connects to a circuit consisting of a
rectifier, followed by an opamp integrator and meter driver.

If you are comfortable working on the circuit I'll be glad to send a
copy of the metering circuit. Although it's from a different model it's
likely to be quite similar except for a few component values. It would
be quick and easy to check the diodes, meter movement and most of the
caps and resistors without disconnecting anything.

Your test unit should work, but of course you have to go up and connect
it each time you check the fence. In my experience, the cheap test units
with multiple neon lights indicating voltage are good to check the
output, but won't last if left connected permanetly.

Be glad you have deer and not elk to keep out. The elk around here will
go through a 6 wire high tensile fence as if it wasn't there, hot or
not. They seem to prefer to bust through even if the fence is low enough
to jump.

WayneJ

On Wed, 12 Jun 2013 08:18:34 -0700
Paul Drahn wrote:

On 6/11/2013 3:26 PM, Karl Townsend wrote:
Plugged in the electric fencer and the meter reads “short” but it
still shocks the **** out of you. Don’t ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that’s needed. or time to buy
another unit? ($250)

Karl

Go to your local farm store and buy a fence tester. You need one anyway
to find breaks in the fence. They are a series of high value resistors
with neon bulbs across the resistors.

Use the tester when you need to, or just hook it permanently to the charger.

Paul

They make Electric Fence Testers nowadays. For instance:

"Get accurate and reliable voltage readings of your fence line or fence
charger with simple, one-touch operation. Use the Zareba® Digital
Electric Fence Tester to measure fence line and fence charger voltage.
-Combines digital accuracy with ease and convenience
-Rugged easy-to-carry pocket-size case made of heavy duty ABS plastic
-Digital accuracy from 500 to 9,900 volts
-Large easy-to-ready LCD display
-volt battery operation (battery included)
-Automatic on/off that prolongs battery life..."

http://www.tractorsupply.com/en/stor...r?cm_vc=-10005

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

On Tue, 11 Jun 2013 20:35:32 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl


Just see how long a spark you can draw from it. The old "weed chopper"
woultd throw a good hat quarter inch spark and burn off 1 inch sumac.

On 2013-06-12, Michael A. Terrell wrote:

Karl Townsend wrote:

Its a Parmak precision brand. Made in USA - KC MO

A proper repair would be huge. I did find this on the web
http://www.dickselectricfencerrepair.com/ But likely, the repair will
be about the same as a new one. Mine is a 6 Joule 7K volt rated unit.
Now, I see you can get 10 Joule 12K volt units. Maybe its time to
upgrade.


Make sure the insulators are clean. They will bleed off a lot of the
energy if they are dirty. It goes without saying, but turn it off
before you do the inspection. ;-)


See if you can find an old Pomona or B&K TV HV probe with a built in
meter. You'll need to add a couple diodes to rectify the AC, but then
it's a simple matter of clipping the lead to ground, and touching the
probe to the wire.

Tektronix made a really nice one -- good up to 40 KV. But
beware. It takes a squirt of a HV dielectric fluid (which is really one
of the now-banned refrigerants), so you are unlikely to get the full
voltage range out of it. (And no, I don't remember if I ever knew what
refrigerant they used -- just one of the FREON family. :-)

If you have some, a squirt will usually last a year or two
before it all leaks out.

And it has four or five trimmer adjustments for proper
waveshape at various frequencies. A *big* box on the BNC (with a collet
lock-on to keep it from jiggling off. :-)

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"Karl Townsend" wrote in message
...
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)


If there is grass or somesuch on the line, a spark will develop at the
charger if you disconnect the wire and hold it far enough away from the
terminal to form a 1/16 in or so wide gap.

wrote:

On Tue, 11 Jun 2013 20:35:32 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl


Just see how long a spark you can draw from it. The old "weed chopper"
woultd throw a good hat quarter inch spark and burn off 1 inch sumac.


What kind of hat did it throw? ;-)

"DoN. Nichols" wrote:

Tektronix made a really nice one -- good up to 40 KV. But beware.
It takes a squirt of a HV dielectric fluid (which is really one
of the now-banned refrigerants), so you are unlikely to get the full
voltage range out of it. (And no, I don't remember if I ever knew
what refrigerant they used -- just one of the FREON family. :-)

If you have some, a squirt will usually last a year or two
before it all leaks out.


A newer refrigerant is being discussed as a possible replacement on
the Tekscope Yahoo group right now.


And it has four or five trimmer adjustments for proper waveshape
at various frequencies. A *big* box on the BNC (with a collet
lock-on to keep it from jiggling off. :-)


I used to use my Heathkit HV probe on low voltage circuits, to
prevent loading in very high impedance circuits. The solid state
Heathkit had some very low voltage ranges, and the probe let you
multiply them by 100.

A guy on the Tekscope Yahoo group builds a HV plug-in for the 7000
series. It will work to 7 kV. There is also a thread on how it's
impossible to make affordable replacements for the extruded rails for
7000 series plug ins. One claims it can't be done in small quantities
for under $200 a set. He refuses to believe that it can be done in a
decent home metalworking shop. I have no 7000 series gear, but from
what I remember it wouldn't be that hard to make an acceptable
replacement since they are looking to build custom plug-ins.

"Michael A. Terrell" wrote in message
m...

A guy on the Tekscope Yahoo group builds a HV plug-in for the 7000
series. It will work to 7 kV. There is also a thread on how it's
impossible to make affordable replacements for the extruded rails
for
7000 series plug ins. One claims it can't be done in small
quantities
for under $200 a set. He refuses to believe that it can be done in
a
decent home metalworking shop. I have no 7000 series gear, but from
what I remember it wouldn't be that hard to make an acceptable
replacement since they are looking to build custom plug-ins.

I have a Tek D10 chassis and its guide rails wouldn't be difficult to
make, though I'm not volunteering. I made some hard drive rails for
Dell desktops that don't look a bit like the green originals, but work
fine.

I've worked for some very talented electrical engineers who couldn't
comprehend a mechanical shape unless they were holding a sample I'd
made.
jsw

Jim Wilkins wrote:

"Michael A. Terrell" ? wrote in message
m...
?
? A guy on the Tekscope Yahoo group builds a HV plug-in for the 7000
? series. It will work to 7 kV. There is also a thread on how it's
? impossible to make affordable replacements for the extruded rails
? for
? 7000 series plug ins. One claims it can't be done in small
? quantities
? for under $200 a set. He refuses to believe that it can be done in
? a
? decent home metalworking shop. I have no 7000 series gear, but from
? what I remember it wouldn't be that hard to make an acceptable
? replacement since they are looking to build custom plug-ins.

I have a Tek D10 chassis and its guide rails wouldn't be difficult to
make, though I'm not volunteering. I made some hard drive rails for
Dell desktops that don't look a bit like the green originals, but work
fine.

I've worked for some very talented electrical engineers who couldn't
comprehend a mechanical shape unless they were holding a sample I'd
made.


The guy wants 20 sets. From what I remember, some aluminum bar stock
and a table saw could make most of the part, and a mill could finish
them. I gave up on him, he wants to destroy existing plug-ins rather
than make new frames. I suggested that he ask on this group to see if
anyone was willing to make them, and to get a price. He started ranting
that no none could do it, and that they wouldn't do it for free, even if
they could. A closed mind is a terrible thing. I've had to make
irreplacable parts with nothing more than a hacksaw & file. He demands
an exact clone of the Tektronix part, and would probably demand a Tek QA
stamp on them.

"Michael A. Terrell" wrote in message
...

... He demands
an exact clone of the Tektronix part, and would probably demand a
Tek QA
stamp on them.

Does this fit?
http://en.wikipedia.org/wiki/Victim_mentality

Jim Wilkins wrote:

"Michael A. Terrell" ? wrote in message
...

? ... He demands
? an exact clone of the Tektronix part, and would probably demand a
? Tek QA
? stamp on them.

Does this fit?
http://en.wikipedia.org/wiki/Victim_mentality


yes. I've worked with people like that, and it isn't pleasant.
They'll give a hundred reasons why something can't be done, then tell
you it was 'Dumb luck' when proven wrong. One would spend up to seven
hours testing and certifying a single board. He insisted that an
improved test fixture that reduced the average time to 17 minutes
couldn't possibly be turning out any good boards. He, and several
others couldn't be convinced of SRF in resistors and capacitors threw a
hissy fit when I designed a broadband DC block to replace the pile of
unlabeled junk that was in use. It consisted of a stack of surface
mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF. It was
assembled in a rectangular bras box with BNC connectors on each end, and
I sued 1/8" brass tubing that was soldered over the center pins of the
BNC connectors, then the caps were soldered to the tubes. They were
flat from 100 KHz to 1400 MHz on a network analyzer with under .5 dB
insertion loss. He, and others insisted that it couldn't possibly work
without a way to switch the individual caps. I even caught one of the
engineers off guard with the design. That design was the first test
fixture to be assigned a part number at Microdyne, and to have the
sketches turned into a detailed CAD drawing and have a B.O.M in the
database.

"Michael A. Terrell" wrote in message
news

He, and several
others couldn't be convinced of SRF in resistors and capacitors
threw a
hissy fit when I designed a broadband DC block to replace the pile
of
unlabeled junk that was in use. It consisted of a stack of surface
mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF.

Like most I learned capacitors as ideal components. It was an
eye-opener to sweep them with a network analyzer and see how much they
deviated, especially the high-Q MLC ones at high frequencies. The
design rule at Mitre (where DC was defined as below 1 GHz) was to do
as you did even with bypass caps, like 0.1uF in parallel with 1000pF,
sometimes stacked on the same pads.

As an experiment I attached a .1uF MLC to a capacitance meter and
heated it with a hot air gun. The capacitance dropped to ~ 1/10th of
its room-temp value. A silver-mica changed almost too little to
detect.
jsw

Jim Wilkins wrote:

"Michael A. Terrell" ? wrote in message
news ?
? He, and several
? others couldn't be convinced of SRF in resistors and capacitors
? threw a
? hissy fit when I designed a broadband DC block to replace the pile
? of
? unlabeled junk that was in use. It consisted of a stack of surface
? mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF.

Like most I learned capacitors as ideal components.


Unfortunately, capacitors are the weakest link in most electronics.


It was an
eye-opener to sweep them with a network analyzer and see how much they
deviated, especially the high-Q MLC ones at high frequencies. The
design rule at Mitre (where DC was defined as below 1 GHz) was to do
as you did even with bypass caps, like 0.1uF in parallel with 1000pF,
sometimes stacked on the same pads.


Some engineers swear by that idea, and others ridicule them. I
worked with very low noise RF gear, and you had to keep all the crap you
could out of the power rails. Any noise, in any rail including ground
would cause excessive phase noise in the wide band synthesizer. It was
band switched with forward biased diodes to reduce the length of the
inductor in the VCO. I've had idiots try to tell me that that method
doesn't work, or that a fraction of a mA is enough to turn it on. You
need enough current to turn it on hard, without damaging the silicon to
keep the RF from modulating the current through the diode. I just
missed buying one of the modules on Ebay by a few bucks, when my browser
crashed 30 seconds before the auction ended.


As an experiment I attached a .1uF MLC to a capacitance meter and
heated it with a hot air gun. The capacitance dropped to ~ 1/10th of
its room-temp value. A silver-mica changed almost too little to
detect.


You should have seen the huge, uncased silver mica caps used in RCA
UHF TV transmitters. They were over $600 each, in the '70s. They were
in the interstage RF coupling, at 1 KW.

Can you do that heat test with any NPO/COG ceramic caps?

On Wed, 12 Jun 2013 23:29:23 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)


If there is grass or somesuch on the line, a spark will develop at the
charger if you disconnect the wire and hold it far enough away from the
terminal to form a 1/16 in or so wide gap.

Even with no grass that will happen due to line capacitance or line
impedence.

On Thu, 13 Jun 2013 09:51:46 -0400, "Michael A. Terrell"
wrote:


wrote:

On Tue, 11 Jun 2013 20:35:32 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl


Just see how long a spark you can draw from it. The old "weed chopper"
woultd throw a good hat quarter inch spark and burn off 1 inch sumac.


What kind of hat did it throw? ;-)
HOT

On Thu, 13 Jun 2013 13:46:44 -0400, "Michael A. Terrell"
wrote:


Jim Wilkins wrote:

"Michael A. Terrell" ? wrote in message
...

? ... He demands
? an exact clone of the Tektronix part, and would probably demand a
? Tek QA
? stamp on them.

Does this fit?
http://en.wikipedia.org/wiki/Victim_mentality


yes. I've worked with people like that, and it isn't pleasant.

No, it isn't. And it sounds like most of the Demonrat party fits that
description, too.


They'll give a hundred reasons why something can't be done, then tell
you it was 'Dumb luck' when proven wrong. One would spend up to seven
hours testing and certifying a single board. He insisted that an
improved test fixture that reduced the average time to 17 minutes
couldn't possibly be turning out any good boards. He, and several
others couldn't be convinced of SRF in resistors and capacitors threw a
hissy fit when I designed a broadband DC block to replace the pile of
unlabeled junk that was in use. It consisted of a stack of surface
mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF. It was
assembled in a rectangular bras box with BNC connectors on each end, and
I sued 1/8" brass tubing that was soldered over the center pins of the
BNC connectors, then the caps were soldered to the tubes. They were
flat from 100 KHz to 1400 MHz on a network analyzer with under .5 dB
insertion loss. He, and others insisted that it couldn't possibly work
without a way to switch the individual caps. I even caught one of the
engineers off guard with the design. That design was the first test
fixture to be assigned a part number at Microdyne, and to have the
sketches turned into a detailed CAD drawing and have a B.O.M in the
database.

clap, clap, clap You got the clap doing that, Mikey.

Kudos, BTW.

--
I have never understood why it is "greed" to want to keep the money you
have earned, but it is not greed to want take someone else's money.
--Thomas Sowell

wrote in message
...
On Wed, 12 Jun 2013 23:29:23 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
. ..
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)


If there is grass or somesuch on the line, a spark will develop at the
charger if you disconnect the wire and hold it far enough away from the
terminal to form a 1/16 in or so wide gap.

Even with no grass that will happen due to line capacitance or line
impedence.

Not in my experience but I'll check it in the morning.

"Michael A. Terrell" wrote in message
...

Can you do that heat test with any NPO/COG ceramic caps?

The Boonton cap meter I have at home was surplus because it no longer
functions well at low capacitance values. I could try but the results
wouldn't mean much.
jsw

On Thu, 13 Jun 2013 17:54:59 -0700, "PrecisionmachinisT"
wrote:


wrote in message
.. .
On Wed, 12 Jun 2013 23:29:23 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
...
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)


If there is grass or somesuch on the line, a spark will develop at the
charger if you disconnect the wire and hold it far enough away from the
terminal to form a 1/16 in or so wide gap.

Even with no grass that will happen due to line capacitance or line
impedence.

Not in my experience but I'll check it in the morning.

It sure does with 2 miles of fence. Or at least it always did when I
was back on the farm. With the Bowman Weed Chopper.

Larry Jaques wrote:

On Thu, 13 Jun 2013 13:46:44 -0400, "Michael A. Terrell"
? wrote:

?
?Jim Wilkins wrote:
??
?? "Michael A. Terrell" ? wrote in message
?? ...
??
?? ? ... He demands
?? ? an exact clone of the Tektronix part, and would probably demand a
?? ? Tek QA
?? ? stamp on them.
??
?? Does this fit?
?? http://en.wikipedia.org/wiki/Victim_mentality
?
?
? yes. I've worked with people like that, and it isn't pleasant.

No, it isn't. And it sounds like most of the Demonrat party fits that
description, too.


Rats turn on each other when the free food runs out.


?They'll give a hundred reasons why something can't be done, then tell
?you it was 'Dumb luck' when proven wrong. One would spend up to seven
?hours testing and certifying a single board. He insisted that an
?improved test fixture that reduced the average time to 17 minutes
?couldn't possibly be turning out any good boards. He, and several
?others couldn't be convinced of SRF in resistors and capacitors threw a
?hissy fit when I designed a broadband DC block to replace the pile of
?unlabeled junk that was in use. It consisted of a stack of surface
?mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF. It was
?assembled in a rectangular bras box with BNC connectors on each end, and
?I sued 1/8" brass tubing that was soldered over the center pins of the
?BNC connectors, then the caps were soldered to the tubes. They were
?flat from 100 KHz to 1400 MHz on a network analyzer with under .5 dB
?insertion loss. He, and others insisted that it couldn't possibly work
?without a way to switch the individual caps. I even caught one of the
?engineers off guard with the design. That design was the first test
?fixture to be assigned a part number at Microdyne, and to have the
?sketches turned into a detailed CAD drawing and have a B.O.M in the
?database.

?clap, clap, clap? You got the clap doing that, Mikey.

Kudos, BTW.


Never tell me something is impossible, unless you can prove it.

On 2013-06-13, Michael A. Terrell wrote:

"DoN. Nichols" wrote:

Tektronix made a really nice one -- good up to 40 KV. But beware.
It takes a squirt of a HV dielectric fluid (which is really one
of the now-banned refrigerants), so you are unlikely to get the full

[ ... ]

A newer refrigerant is being discussed as a possible replacement on
the Tekscope Yahoo group right now.

Great!

[ ... ]

A guy on the Tekscope Yahoo group builds a HV plug-in for the 7000
series. It will work to 7 kV. There is also a thread on how it's
impossible to make affordable replacements for the extruded rails for
7000 series plug ins. One claims it can't be done in small quantities
for under $200 a set. He refuses to believe that it can be done in a
decent home metalworking shop. I have no 7000 series gear, but from
what I remember it wouldn't be that hard to make an acceptable
replacement since they are looking to build custom plug-ins.

Hmm ... without checking mine out, I think that it could be
possible to set up a stack of cutters on the arbor of a horizontal
spindle mill, and make the necessary shape in one pass with long stock.
Then you *might* need to flip it over and mill the inside cavities.

I forget whether there is perforated metal in holes through the
rails. If so -- a bit more milling after flipping it over, and CNC would
be the winner there.

And of course, it could all be done with CNC. But with enough
of them to be made I think that a horizontal mill would win hands down,
at least for the bottom profile.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 2013-06-13, Michael A. Terrell wrote:

The guy wants 20 sets. From what I remember, some aluminum bar stock
and a table saw could make most of the part, and a mill could finish
them.

For only 20 sets, the custom cutter stack for a horizontal mill
would probably not be worth the time and the custom grinding..

I gave up on him, he wants to destroy existing plug-ins rather
than make new frames. I suggested that he ask on this group to see if
anyone was willing to make them, and to get a price. He started ranting
that no none could do it, and that they wouldn't do it for free, even if
they could. A closed mind is a terrible thing. I've had to make
irreplacable parts with nothing more than a hacksaw & file.

I used the horizontal mill and an index head to make a
replacement gear for use inside a differential vertical plugin. I think
that I posted a web page about the project a couple of years ago. :-)

If he is stripping a frame to make each, he probably would need
the front and rear panels too. The front is likely an injection
molding, but the rear is pretty simple sheet metal work, IIRC.

He demands
an exact clone of the Tektronix part, and would probably demand a Tek QA
stamp on them.

Well ... the QA stamp could be forged, too. :-)

The empty chassis for the TM-500 plugins would be a nice
starting point, except that they are not long enough. (I considered
using one (which I have) to make a test extender for the 'scope
mainframe, and this is how I know this.

Custom machined parts would offer him a better choice of mounting
certain parts -- such as those which need heat-sinking.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote:

On 2013-06-13, Michael A. Terrell ? wrote:
?
? "DoN. Nichols" wrote:
??
?? Tektronix made a really nice one -- good up to 40 KV. But beware.
?? It takes a squirt of a HV dielectric fluid (which is really one
?? of the now-banned refrigerants), so you are unlikely to get the full

[ ... ]

? A newer refrigerant is being discussed as a possible replacement on
? the Tekscope Yahoo group right now.

Great!

[ ... ]

? A guy on the Tekscope Yahoo group builds a HV plug-in for the 7000
? series. It will work to 7 kV. There is also a thread on how it's
? impossible to make affordable replacements for the extruded rails for
? 7000 series plug ins. One claims it can't be done in small quantities
? for under $200 a set. He refuses to believe that it can be done in a
? decent home metalworking shop. I have no 7000 series gear, but from
? what I remember it wouldn't be that hard to make an acceptable
? replacement since they are looking to build custom plug-ins.

Hmm ... without checking mine out, I think that it could be
possible to set up a stack of cutters on the arbor of a horizontal
spindle mill, and make the necessary shape in one pass with long stock.
Then you *might* need to flip it over and mill the inside cavities.

I forget whether there is perforated metal in holes through the
rails. If so -- a bit more milling after flipping it over, and CNC would
be the winner there.

And of course, it could all be done with CNC. But with enough
of them to be made I think that a horizontal mill would win hands down,
at least for the bottom profile.


Page 144 of this manual shows the way they are made. Without one in
hand, it's the best reference that I can give you right now.

http://bama.edebris.com/download/tek/7b85/Tektronix-7B85%20Delaying%20Time%20Base.pdf

"DoN. Nichols" wrote:

On 2013-06-13, Michael A. Terrell ? wrote:

? The guy wants 20 sets. From what I remember, some aluminum bar stock
? and a table saw could make most of the part, and a mill could finish
? them.

For only 20 sets, the custom cutter stack for a horizontal mill
would probably not be worth the time and the custom grinding..

? I gave up on him, he wants to destroy existing plug-ins rather
? than make new frames. I suggested that he ask on this group to see if
? anyone was willing to make them, and to get a price. He started ranting
? that no none could do it, and that they wouldn't do it for free, even if
? they could. A closed mind is a terrible thing. I've had to make
? irreplacable parts with nothing more than a hacksaw ? file.

I used the horizontal mill and an index head to make a
replacement gear for use inside a differential vertical plugin. I think
that I posted a web page about the project a couple of years ago. :-)

If he is stripping a frame to make each, he probably would need
the front and rear panels too. The front is likely an injection
molding, but the rear is pretty simple sheet metal work, IIRC.

? He demands
? an exact clone of the Tektronix part, and would probably demand a Tek QA
? stamp on them.

Well ... the QA stamp could be forged, too. :-)

The empty chassis for the TM-500 plugins would be a nice
starting point, except that they are not long enough. (I considered
using one (which I have) to make a test extender for the 'scope
mainframe, and this is how I know this.

Custom machined parts would offer him a better choice of mounting
certain parts -- such as those which need heat-sinking.


Are you a member of the Yahoo TekScopes group? Some of the people
there were engineers at Tektronix.

http://groups.yahoo.com/group/TekScopes


Here is a Wiki about tektronix products:

http://w140.com/tekwiki/wiki/Main_Page#Carts


Here is a nice collection of Tektronix manuals.

https://docs.google.com/folder/d/0B7w5p5pSKM5gRFhTY2V0SlNSRVE/edit

"Michael A. Terrell" on Thu, 13 Jun 2013
13:46:44 -0400 typed in rec.crafts.metalworking the following:

Jim Wilkins wrote:

"Michael A. Terrell" ? wrote in message
...

? ... He demands
? an exact clone of the Tektronix part, and would probably demand a
? Tek QA
? stamp on them.

Does this fit?
http://en.wikipedia.org/wiki/Victim_mentality


yes. I've worked with people like that, and it isn't pleasant.
They'll give a hundred reasons why something can't be done, then tell
you it was 'Dumb luck' when proven wrong. One would spend up to seven
hours testing and certifying a single board. He insisted that an
improved test fixture that reduced the average time to 17 minutes
couldn't possibly be turning out any good boards. He, and several
others couldn't be convinced of SRF in resistors and capacitors threw a
hissy fit when I designed a broadband DC block to replace the pile of
unlabeled junk that was in use. It consisted of a stack of surface
mount caps. I use .33 uF. .033 uF .0033 uF 330 pF and 33 pF. It was
assembled in a rectangular bras box with BNC connectors on each end, and
I sued 1/8" brass tubing that was soldered over the center pins of the
BNC connectors, then the caps were soldered to the tubes. They were
flat from 100 KHz to 1400 MHz on a network analyzer with under .5 dB
insertion loss. He, and others insisted that it couldn't possibly work
without a way to switch the individual caps. I even caught one of the
engineers off guard with the design. That design was the first test
fixture to be assigned a part number at Microdyne, and to have the
sketches turned into a detailed CAD drawing and have a B.O.M in the
database.

And after you sued the 1/8" brass tubing, too.
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

"Michael A. Terrell" on Thu, 13 Jun 2013
09:51:46 -0400 typed in rec.crafts.metalworking the following:

wrote:

On Tue, 11 Jun 2013 20:35:32 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl


Just see how long a spark you can draw from it. The old "weed chopper"
woultd throw a good hat quarter inch spark and burn off 1 inch sumac.


What kind of hat did it throw? ;-)

He did say a "good hat" - so a Stetson, maybe?
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

on Thu, 13 Jun 2013 17:25:37 -0400 typed in
rec.crafts.metalworking the following:
On Thu, 13 Jun 2013 09:51:46 -0400, "Michael A. Terrell"
wrote:


wrote:

On Tue, 11 Jun 2013 20:35:32 -0700, "PrecisionmachinisT"
wrote:


"Karl Townsend" wrote in message
.. .
Plugged in the electric fencer and the meter reads "short" but it
still shocks the **** out of you. Don't ask me how I know this.


****ed on it, did you ?

Not having a volt indication will be a real problem, no way to know if
grass etc. is knocking down the effectiveness. A fencer puts out a
high volt burst a small percent of the time. On the order of 7K volts
for 50 miliseconds once per second. Is there an easy way to add a volt
meter? Just a relative indication is all that's needed. or time to buy
another unit? ($250)

Karl


Just see how long a spark you can draw from it. The old "weed chopper"
woultd throw a good hat quarter inch spark and burn off 1 inch sumac.


What kind of hat did it throw? ;-)
HOT

A hot hat? Must have been a fireman's hat. B-)
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."