Re: AM503B current amplifier questions.


Hi Tom,
That did happen, and Tegam continued to sell a few of the most lucrative
TM5000 products for a while, but the sale to Tegam came after Tek stopped
producing Service Manuals for the new TM5xx/TM5xxx products they introduced.
Dennis Tillman W7PF

-----Original Message-----
From: []
Sent: Wednesday, November 04, 2015 10:27 PM
Subject: Re: [TekScopes] AM503B current amplifier questions.

Didn't they pass the whole line off to Tegam? They then dropped everything.
Also, no help even for paid service.

----- Original Message -----
From: 'Dennis Tillman' [TekScopes]
Sent: Wednesday, November 04, 2015 11:18 PM
Subject: RE: [TekScopes] AM503B current amplifier questions.

About the time the AM503B (I am referring to the B model only) came out
Tek stopped including schematics in their manuals. They became Instruction
Manuals rather than Service Manuals. There was nothing that might be of use
to a service technician - no theory of operation, no schematics, no parts
lists (mechanical or electronic), no calibration procedure, etc. This was
one manifestation that Tek's days were numbered. Another one of the TM500
instruments that suffered the same fate was the TVC501 Time-Interval to
Voltage Converter.

Dennis Tillman W7PF

-----Original Message-----
From: []
Sent: Wednesday, November 04, 2015 6:09 PM
Subject: Re: [TekScopes] AM503B current amplifier questions.


That is a very popular piece of test instrument. There must be dozens of
group members who will be able to help you. I have a manual, but I do not
have any time to scan it for you. Someone must have a PDF already prepared.

On Wed, Nov 4, 2015 at 1:02 PM, [TekScopes] <> wrote:

> Picked up an AM503B on our favorite source. It does not work, how
> strange is that.
> There seems to be vary limited info on this unit, i.e. no schematics
> even for money.
> The scope output is hung positive at 0.4 volts and there is a fault
> code of 592 and it is flashing.
> Looking at the old 503 amplifier shows that there is +3 volts on pin A
> and
> -3 volts on pin D. On this unit, I get about +/- 0.5 volts. This seems
> to power the probe. The internal supplies seem to be good as far as I
> can tell. But without a schematic I am shooting in the dark.
> Has anyone on this group ever worked on one of these? Any ideas?
> Best regards,
> Tom
Gary Robert Bosworth
Tel: 310-317-2247

Posted by: Gary Robert Bosworth <>
Posted by: "Tom Miller" <>

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