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Restoring 545b


Jayadamski728@...
 

Hi all, I am from London uk and I am restoring a 545b which I obtained from ebay for £30. It was in a bad state when I recieved it and had 7 vacuum tubes missing. I now have got it to the point where I get a dot on the screen from both A and B channels and it seems the vertical output is not working at all. I think a lot of the problems is with dirty contacts on the rotary switches ...
I was wondering what is the best way to clean these as I have tried to clean them with alcohol and cotton buds. Do you guys have a good way to clean them and get all the oxide off ?


@0culus
 

I have been working on a 585A and an assortment of plugins. I cleaned up the Type CA plugin's dirty (exposed) controls with carefully applied deoxit. It definitely helped. You have to be really careful not to make a mess with these canned products since they typically are full blast or nothing.

Sean


Jayadamski728@...
 

Hi all

One of the bridge rectifier diodes in the power supply has shorted ... I was wondering what a suitable replacement would be ?


Stephen
 

On Sat, Jul 11, 2020 at 11:28 PM, <Jayadamski728@...> wrote:


Hi all

One of the bridge rectifier diodes in the power supply has shorted ... I was
wondering what a suitable replacement would be ?
Look at the schematic which you could download from TekWiki, I guess.
It’ll probably tell you the characteristics of that rectifier. Replace it with a suitable modern replacement having the same voltages/power handling. That shouldn’t be too hard to find.


Chuck Harris
 

It would help, only a little, to know which diode,

There are about 6 1N3194's (0.75A, 400PIV), which
can be replaced with a 1N4007 (1A, 1000PIV).

-Chuck Harris



Jayadamski728@... wrote:

Hi all

One of the bridge rectifier diodes in the power supply has shorted ... I was wondering what a suitable replacement would be ?