Hi forum members,
joining as a new member with a specific need, hope that's alright.
Recently bought above mentioned 609k valve receiver but it turns out to be in a pretty bad state with at least one, long time ago, attempt at repair, probably doing more harm than good. Subsequently it must have been stored in an attic as it's full of dusty white powder, insect wings and seeds!
Anyway, I've disassembled to the point where I can access the components on the main tuner pcb and have removed all the obvious capacitor candidates for replacement and checked the values of all resistors in order to find the ones that are intolerant (sorry about that), I mean the ones that don't measure correctly for their markings. Getting ready to remove those too and replace with new old components that I've ordered (after xmas).
Apart from the dirt and the filter capacitor that had been added, to 'repair' it I imagine, I found a loose black lead that may have been the cause of some of the initial problems. Also a number of the valves, including one of the output el84s, were a milky white colour which is, I think, a pretty good indication that they're not in good shape. The face plate has also lost two small areas of paint where someone put some sellotape. I'm planning to paint in the small bare patches with some custom colour mixed paint, grey blue.
That's where I am at the moment. I have been looking for a schematic but have not found one yet. It would be very interesting to hear if anyone has experience of restoring a similar receiver.
I also have a 609k minette, which is just the FM receiver. This also needs attention as the face plate has a smaller bare patch and it only gets reception on FM mono with the tuning eye valve indicating weakish reception. I haven't yet opened that one up but expect it to be cleaner than the bandmaster but equally in need of attention to non spec components.
With the bandmaster I've removed all electrolytics and anything that resembles one. Also removed two black plasticky 10,000pf cap, one of which appeared to have partially melted. The remaining caps are red disks (ceramics?) and small silver coloured axials between the fascia dials.
Any thoughts about the reliability of these components particularly bearing in mind that the apparatus appears to have been quite severely stressed at some point.
I'll keep you posted with progress though that won't happen till after xmas 'n new year. Can also post some pics if anyone is interested as lacking the cicuit diagram I'm using pics and notes to try to keep track of what goes where.
Brian