[Milsurplus] RT-1523B circuits

[robinson at tuberadio.com]

Hi all,

I have an RT-1523B on the bench at the moment.
No display, just blank.
I used to work.
Now it has audio noise, which varies with the volume control.
No rx or tx.
Power supply voltages are correct.

I have downloaded manuals from the web
but they are slightly different and have no circuits.
The trouble shooting flow charts have not helped.
Does anyone know of any circuits available?

regards
Ray