Capacitance Meter Recommendation
 

On Sun, 26 Jun 2005 15:50:04 +0200 (CEST), Nomen Nescio
wrote:

I'm just starting the process of bringing back from the dead a very old
1950's RCA color television. The CTC-7 chassis is very ugly looking, with
over 75 paper capacitors. There are also two Sprague can-type
electrolytics, 3 caps in each can. Will have to make something to replace.
Powering on is out of the question until I can replace numerous components.

I want to buy a capacitance meter to check both the caps that I'm replacing
and the replacement parts I will install. I've been looking at a BK
Precision 810c Capacitance Meter. Or maybe I'll buy a Fluke 177. But then
I read this from a post in 2002:

"don't expect the Capacitance measurements (of a DMM) to equal that of even
the cheapest C meter. Even on the "expensive" meters." Paul Grohe,
sci.electronics.basics

My concern is that the capacitor checker function built into a
multi-purpose DMM isn't as good as a stand-alone capacitance meter. Is
there any truth to this statement?

Nearly everyone who is into restoring old radios or TV's (myself
included) replace all of the paper caps with polypropylenes or mylars
and all of the electrolytics with new ones. If one of them is still
good, it is likely to fail soon, so why not just replace them all?

Do that and you do not need a meter as the new caps are surely good.

But, if you really want a cap meter I can offer the ESR60 which
measures ESR and value at US$149.00. See
www.anatekcorp.com/testequipment/atlasesr60.htm for details.

John
The Electronic Repair Center at www.anatekcorp.com

On Sun, 26 Jun 2005 15:50:04 +0200 (CEST), Nomen Nescio
wrote:

I'm just starting the process of bringing back from the dead a very old
1950's RCA color television. The CTC-7 chassis is very ugly looking, with
over 75 paper capacitors. There are also two Sprague can-type
electrolytics, 3 caps in each can. Will have to make something to replace.
Powering on is out of the question until I can replace numerous components.

I want to buy a capacitance meter to check both the caps that I'm replacing
and the replacement parts I will install. I've been looking at a BK
Precision 810c Capacitance Meter. Or maybe I'll buy a Fluke 177. But then
I read this from a post in 2002:

"don't expect the Capacitance measurements (of a DMM) to equal that of even
the cheapest C meter. Even on the "expensive" meters." Paul Grohe,
sci.electronics.basics

My concern is that the capacitor checker function built into a
multi-purpose DMM isn't as good as a stand-alone capacitance meter. Is
there any truth to this statement?

If you want to verify electrolytic capacitors, you have to be able to
check the ESR.

Tom

Why not tuen on the set and see what happens. The vacuum tube color
sets, which I worked on in the 50's to go thru college, were very
forgiving of temporary overloads, etc. If you are familiear with
tubes, you understand there is much more margin than with transistors
as far as temporary overloads are concerned.

H. R.(Bob) Hofmann

On Sun, 26 Jun 2005 19:40:07 +0200 (CEST), Nomen Nescio
wrote:

On Sun, 26 Jun 2005 11:30:23 -0400, John Bachman
wrote:

Nearly everyone who is into restoring old radios or TV's (myself
included) replace all of the paper caps with polypropylenes or mylars
and all of the electrolytics with new ones. If one of them is still
good, it is likely to fail soon, so why not just replace them all?

There are only three electrolytics in the entire set, one has already been
replaced. The remaining caps are paper, mica, and ceramic. From my
reading up on caps, it's the paper ones that need replacement. Over the
years some of the paper caps have been replaced with orange drops. So I
don't have to do all of them. Still, it's a literal bird's nest of wires
on the underside of the chassis. Seems like back in the 1950's, the way a
TV was designed (or maybe it was just RCA) such that one component wouldn't
short out another, was to simply bend the leads so that nothing touches.
Frightening! The TV may also have transformer problems, although the
flyback looks very clean, with no signs of arcing.

I've read about the ESR meters, just never used one before. And don't
quite understand how it could work with a cap in circuit, as other
components would effect the values of the component under test (like an
inductor in parallel with the capacitor).

First we have to establish that we are talking about two very
different applications: old TV/radio restoration and ESR.

When your TV was designed no one worried much about ESR, it just was
not an important characteristic of capacitors, electrolytic and
otherwise. So ESR measurement is not a big deal in those situations.
I only mentioned it thinking that you might have other applications in
which ESR measurement would be useful.

You are correct in that ESR is affected by other components in the
circuit. Most ESR measurements are made on electrolytic filter
capacitors, not frequency sensitive circuits. In those case, the ESR
can be measured in-circuit as long as the meter does not forward bias
any semiconductors in the circuit. Not a problem with 50's TVs :-)

John

On Sun, 26 Jun 2005 20:40:03 +0200 (CEST), Nomen Nescio
wrote:

On Sun, 26 Jun 2005 11:30:23 -0400, John Bachman
wrote:

But, if you really want a cap meter I can offer the ESR60 which
measures ESR and value at US$149.00. See
www.anatekcorp.com/testequipment/atlasesr60.htm for details.

According to the specifications for your meter, the minimum Capacitance
measurement range is 1uF. How would this meter work for paper capacitors,
when all of the fixed paper capacitors in my set are all under 1uF, with
the smallest being .0018uF and the largest being .47uF. Just doesn't seem
the appropriate product for my application.

See my post to your other question.

Yes, the ESR60 will not measure the value of the paper capacitors you
are dealing with.

John

Don`t know much about TV`s,but how good would a 1950`s TV picture look
compared to say, a new HDTV? just wondering wouldn`t it be a lot more worth
repairing a broken HDTV or plasma TV? were TV`s built a lot better in the
50`s?
"Jamie" wrote in message
...
Nomen Nescio wrote:

I'm just starting the process of bringing back from the dead a very old
1950's RCA color television. The CTC-7 chassis is very ugly looking,
with
over 75 paper capacitors. There are also two Sprague can-type
electrolytics, 3 caps in each can. Will have to make something to
replace.
Powering on is out of the question until I can replace numerous
components.

I want to buy a capacitance meter to check both the caps that I'm
replacing
and the replacement parts I will install. I've been looking at a BK
Precision 810c Capacitance Meter. Or maybe I'll buy a Fluke 177. But
then
I read this from a post in 2002:

"don't expect the Capacitance measurements (of a DMM) to equal that of
even
the cheapest C meter. Even on the "expensive" meters." Paul Grohe,
sci.electronics.basics

My concern is that the capacitor checker function built into a
multi-purpose DMM isn't as good as a stand-alone capacitance meter. Is
there any truth to this statement?

you will also need a variable HV supply to check for leakage, more like
a HI-POT unit.

Dolemite wrote:
Don`t know much about TV`s,but how good would a 1950`s TV picture look
compared to say, a new HDTV? just wondering wouldn`t it be a lot more worth
repairing a broken HDTV or plasma TV? were TV`s built a lot better in the
50`s?

Hi...

Memories, my (must be young) friend, memories :)

Gee, even reading about it brings 'em back. Had forgotten
about those boiling hot shields on the if's :) And trying
to find the key to put hot tubes back in the tuner. And
squeezing wax paper caps gently with a pair of long nose to
test them.

And cleaning tuner contacts... and fine tuning the fine
tuning... and real solid wood cabinets that weighed tons...
and antennas on the roof... more and more keeps flooding back :)

Memories, wonderful memories :)

Take care.

Ken

Surely you would replace all those caps as a matter of course, as well as the
high value resisters

David

Nomen Nescio wrote:

I'm just starting the process of bringing back from the dead a very old
1950's RCA color television. The CTC-7 chassis is very ugly looking, with
over 75 paper capacitors. There are also two Sprague can-type
electrolytics, 3 caps in each can. Will have to make something to replace.
Powering on is out of the question until I can replace numerous components.

I want to buy a capacitance meter to check both the caps that I'm replacing
and the replacement parts I will install. I've been looking at a BK
Precision 810c Capacitance Meter. Or maybe I'll buy a Fluke 177. But then
I read this from a post in 2002:

"don't expect the Capacitance measurements (of a DMM) to equal that of even
the cheapest C meter. Even on the "expensive" meters." Paul Grohe,
sci.electronics.basics

My concern is that the capacitor checker function built into a
multi-purpose DMM isn't as good as a stand-alone capacitance meter. Is
there any truth to this statement?

Nomen Nescio wrote:

I'm just starting the process of bringing back from the dead a very old
1950's RCA color television. The CTC-7 chassis is very ugly looking, with
over 75 paper capacitors. There are also two Sprague can-type
electrolytics, 3 caps in each can. Will have to make something to replace.
Powering on is out of the question until I can replace numerous components.

I want to buy a capacitance meter to check both the caps that I'm replacing
and the replacement parts I will install. I've been looking at a BK
Precision 810c Capacitance Meter. Or maybe I'll buy a Fluke 177. But then
I read this from a post in 2002:

"don't expect the Capacitance measurements (of a DMM) to equal that of even
the cheapest C meter. Even on the "expensive" meters." Paul Grohe,
sci.electronics.basics

My concern is that the capacitor checker function built into a
multi-purpose DMM isn't as good as a stand-alone capacitance meter. Is
there any truth to this statement?

you will also need a variable HV supply to check for leakage, more like
a HI-POT unit.

Nomen Nescio wrote:

On 26 Jun 2005 12:42:40 -0700, wrote:


Why not tuen on the set and see what happens. The vacuum tube color
sets, which I worked on in the 50's to go thru college, were very
forgiving of temporary overloads, etc. If you are familiear with
tubes, you understand there is much more margin than with transistors
as far as temporary overloads are concerned.


Believe me, this set ain't in power-on condition. I was told that the set
was broken, hadn't been turned on in years, sat in an unheated garage for
years, and the power cord was snipped off. Upon a visual inspection, the
horizontal output tube was up to air (getter all white), and the chassis
was only partially bolted in place, bolts finger tight, another bolt
rolling around loose inside, along with several tube shields. The main
power transformer has leaked a dark brown goo down on the chassis (the
chassis sits vertically on its side), with the video board all gunked up.
The CRT board took a nice hit, cracking the neck socket. Fortunately the
wires to the socket are all intact, and the vacuum is still there. Believe
me, there have been many hands in this set, with many modifications from
the schematic I've obtained. The CRT is a 21FBP22, replacing the original
21CYP22. The old man who used to own it must have been in love with the
thing, because it appears the CRT has been exchanged twice from when it was
purchased in 1957. Looks like around the mid 1970's the repair shop told
the guy to give it a decent burial, because that's when the repair tags
end. They probably didn't want to work on it anymore.

So anyway, I'm going to give this my best shot. Have a whole bunch of caps
on order. Once I get the power supply cleaned up, I may attempt to fire it
up (only talking figuratively he-) and see if I can get raster....

you may find that the flyback is out in left field.
good luck in locating another.
it was a common problem of having bad flyback transformers
for various reasons.
one of the common problems was losing the horizontal drive, the tube
would heat up thus popping it self during its melt down and heating the
heck out of the flyback melting the wax while in process.

On Sun, 26 Jun 2005 18:29:15 -0400, "Dolemite" wrote:

Don`t know much about TV`s,but how good would a 1950`s TV picture look
compared to say, a new HDTV? just wondering wouldn`t it be a lot more worth
repairing a broken HDTV or plasma TV? were TV`s built a lot better in the
50`s?
"Jamie" wrote in message

Slide over to rec.antiques.radio+phono and see how many people are
into restoration of old electronics. It might give you a different
perspective.

John