Re: CG551AP - has anyone seen this problem before?
This time the problem was fuse A5F1141 (1.5A fast) in the HV supply circuit (top left of schematic <18>). I replaced it with the same specification and it all works again.toggle quoted messageShow quoted text
Multiple power cycles with no problems at all.
The original fuse must have just died of old age ...
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: 04 March 2020 04:14
Subject: Re: [TekScopes] CG551AP - has anyone seen this problem before?
There is a handful of mercury wetted relays underneath
a shield. One of the relays is probably sticking shut,
and installing a 50 ohm load all the time. This makes
the voltage output 1/2 what it should be, and trips the
Also, virtually all of the transistors are plugged into
the board. Many have heatsinks. If the cables aren't
dressed properly when you install the boards, they can
push the transistors cockeyed in their sockets and then
can short to the inter board shields.
David C. Partridge wrote:
Oh no, not again!!! Yes apart from not getting errors 56 and 57 ...