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Looking for a better in circuit ESR meter


Richard Knoppow
 

IN Circuit explains it. Of course, the problem is that you may have trouble discriminating what is in the capacitor from what is external to it. You are up against Kirchoff's law and its equivalents in AC (Norton and Thevinin).

On 5/16/2020 12:55 PM, Reginald Beardsley via groups.io wrote:
The issue is doing it reliably in-circuit on an instrument for which there is very meager service information. All I've got for the PS is a schematic with no part values. Multiple caps in parallel are shown as a single cap. And access makes removing the caps for better testing a major chore. It would be very difficult to get them back in and with almost 20 caps wedged together down under the edge of major chassis parts, it's not at all clear it could be done without completely disassembling the supply. The construction is such that it would probably take 4 hours to take apart and another 4 hours to assemble.

The PS has 9 output voltage adjustments and 8 connections on the PS connector. I've not yet determined where I can access the -12V output. The service manual procedure is "replace module". Test points? We don't need no stinking test points!

The PS connector was poorly chosen and the +/- 5 V connections burn up. This unit had a factory repair under warranty. It consisted of soldering the PS to the main board with #12 AWG wire.

The symptoms make me suspect that I've got noise on a power rail, but the SMPS makes it very hard to probe for that.

The LeCroy DDA-120 functions, but the front panel response is intermittent. I've replaced the cable and the switch contact board and I've swapped the processor boards without significant change in behavior.

I'm Not Having Fun!
Reg
--
Richard Knoppow
dickburk@...
WB6KBL


David Kuhn
 

" I just ordered an EDS-88A II designed by Dave Miga from Merced
Electronics. I'll see if it can successfully test the wad of caps that the
BSIDE ESR02 Pro (aka Arduino LCR/transistor tester) and the Peak Atlas
ESR70 cannot."

I have one and love it. I can not speak anymore of ESR as this is a TEK
Scope Forum (or so I have been previously told and probably should not even
mention that I like the EDS-88A).



On Sat, May 16, 2020 at 10:21 AM Reginald Beardsley via groups.io
<pulaskite=yahoo.com@groups.io> wrote:

I'm using the groups.io website as my mailbox was getting swamped. I
could make no sense of your ASCII art. Please get on the website and look
at your own post. That's what I see.

I just ordered an EDS-88A II designed by Dave Miga from Merced
Electronics. I'll see if it can successfully test the wad of caps that the
BSIDE ESR02 Pro (aka Arduino LCR/transistor tester) and the Peak Atlas
ESR70 cannot.

Both of those work for a lot of caps, but not for this tightly packed set
of 12. They get reported as under 200 pF. Getting one back in after
removal will be a huge pain. So I *really* want to be sure it's bad before
removing one.

I'm trying to sort out a LeCroy DDA-120 which is misbehaving as if the
front panel controls were intermittent. I suspect that I've got a noisy PS
rail, but on an SMPS that's very hard to test because of ground access. I
only have a few places I know of I can access the rails and no ground close
enough to not have a huge problem with magnetic pickup.

Reg




Roy Morgan
 

Chuck,

I have discovered where to change the message font in my mail program (Mail on my Mac. Mail -> Preferences->Fonts & colors).
There are about one bazillion choices of fonts.

Can you suggest one likely to work well?

Thanks much.


On May 16, 2020, at 9:42 AM, Chuck Harris <cfharris@...> wrote:

If my ascii schematic isn't working it is likely because you
have your browser set to substitute your favorite font for the
font chosen by the sender.
Roy Morgan
K1LKY since 1958
k1lky68@...


 

Courier new is good for ascii artwork as it's mono-pitch.

D.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Roy
Morgan
Sent: 12 August 2020 16:32
To: TekScopes@groups.io
Subject: Re: [TekScopes] Looking for a better in circuit ESR meter

Chuck,

I have discovered where to change the message font in my mail program (Mail
on my Mac. Mail -> Preferences->Fonts & colors).
There are about one bazillion choices of fonts.

Can you suggest one likely to work well?

Thanks much.


On May 16, 2020, at 9:42 AM, Chuck Harris <cfharris@...> wrote:

If my ascii schematic isn't working it is likely because you
have your browser set to substitute your favorite font for the
font chosen by the sender.
Roy Morgan
K1LKY since 1958
k1lky68@...


toby@...
 

On 2020-08-12 11:32 a.m., Roy Morgan wrote:
Chuck,

I have discovered where to change the message font in my mail program (Mail on my Mac. Mail -> Preferences->Fonts & colors).
There are about one bazillion choices of fonts.

Can you suggest one likely to work well?
If I recall the context of this thread: Anything monospaced. e.g.
Courier is standard on OS X and Windows.

--Toby

Thanks much.


On May 16, 2020, at 9:42 AM, Chuck Harris <cfharris@...> wrote:

If my ascii schematic isn't working it is likely because you
have your browser set to substitute your favorite font for the
font chosen by the sender.
Roy Morgan
K1LKY since 1958
k1lky68@...







Chuck Harris
 

Roy,

Generally, pick any that is a fixed spaced font... such as
any of the typewriter fonts: Pica, Elite, Courier...

-Chuck Harris

Roy Morgan wrote:

Chuck,

I have discovered where to change the message font in my mail program (Mail on my Mac. Mail -> Preferences->Fonts & colors).
There are about one bazillion choices of fonts.

Can you suggest one likely to work well?

Thanks much.


On May 16, 2020, at 9:42 AM, Chuck Harris <cfharris@...> wrote:

If my ascii schematic isn't working it is likely because you
have your browser set to substitute your favorite font for the
font chosen by the sender.
Roy Morgan
K1LKY since 1958
k1lky68@...








Carsten Bormann
 

On 2020-08-12, at 17:32, Roy Morgan <k1lky68@...> wrote:

Can you suggest one likely to work well?
I’m not Chuck, but highly readable monospace fonts include Andale Mono (Windows/Office font) and Menlo (Apple font).

Grüße, Carsten


Glenn Little
 

Use any fixed with font. Courier works well.

Glenn

On 8/12/2020 11:32 AM, Roy Morgan wrote:
Chuck,

I have discovered where to change the message font in my mail program (Mail on my Mac. Mail -> Preferences->Fonts & colors).
There are about one bazillion choices of fonts.

Can you suggest one likely to work well?

Thanks much.


On May 16, 2020, at 9:42 AM, Chuck Harris <cfharris@...> wrote:

If my ascii schematic isn't working it is likely because you
have your browser set to substitute your favorite font for the
font chosen by the sender.
Roy Morgan
K1LKY since 1958
k1lky68@...





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of the Amateur that holds the license"


Precaud
 

I have been successfully using an HP 4815A for in-circuit ESR testing for more than 20 years.