[GreenKeys] Navy CV-3510A Converter Repair/Recap

[Duncan Brown]

Jeff,

What ship are you working on?

We have a pair of CV-3510As at the AWA Museum, but I've never  had a 
chance to check them out.

On 08-Mar-23 23:39, Jeff G wrote:
>  The demod board is a mess, mostly around the bandpass filters. It 
> actually works...mostly...but for example, if I feed a solid 1575hz 
> mark signal to it from a signal gen, it'll be good for maybe a minute 
> or two, and then "fade" out. 1-2 mins later, fades back in again. When 
> its good, it decodes and prints, but then out of the blue, it fades 
> and just stops printing for 1-2 mins, and starts printing again.I 
> think it's adjustments, but the manual is fairly hard to follow in 
> this regard. The patterns on the CRT look like a trippy 1960s disco 
> video vs what I expect.
Sounds like a bad connection/solder joint. When things heat up, 
connection is broken.  When cools down, connection is remade and thing 
work OK.  You just need to follow the circuit to see where it quits.  Or 
try poking at the board when it quits to see if you can make it come back..

>
> Also the CRT is very dim; heater voltage looks OK, and I have the 
> brightness as high as it'll go.
>
That is typical of the old CRTs.  I've replaced the  CRT in the Museum's 
Dovetron a couple of times in the past ten years.

Good luck & have fun,

Duncan Brown, K2OEQ
USASA    31J30

i-Telex: 212503

Antique Wireless Assoc. Museum,
   Asst. Curator, Commercial Equipment
(also chief TTY op & repairman)

www.antiquewireless.org
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