03-28-2020, 09:54 PM
And so to work...
The first thing I noticed was that there is plenty to replace beneath the preset button and coil assemblies, so the wires were labelled and desoldered. I had hoped that the two parts could stay soldered together, but there was another connection to the coil frame that was beneath the whole thing. So 12 wires were dutifully desoldered, and then the two parts could be out of the way. This is safer overall, as the preset coils have very vulnerable fine wires.
I cut a circle of cardboard and covered the speaker, also drew out a diagram of the chassis, and checked off which valve locates in each socket.
The three electrolytics were removed from the chassis. I think I will restuff these, and remove the parts added beneath. The wiring looks to be clear enough - remember, I have no documentation to go on whatsoever.
The transformers were checked for continuity, and all test well, also the speaker field coil. The mains switch was cleaned, and with all valves removed, power was applied using the "dim bulb" tester. Not a flicker from the bulb, but the dial lights lit up, and all secondary voltages seemed in order. There's a good 350V AC on each half of the HT winding, so they meant business, feeding the two #41 output valves.
The tuning drive string broke, I've ordered some new cord. The mechanism confused me at first, there are two strings - one connecting the drum to the tuning shaft, the other connecting to the dial mechanism.
Lastly, I tested removal of the rust. It seems this might well clean up better than expected so gentle scrubbing with a kitchen scourer, plus rust removal gel will be pursued first.
Cheers
Ed
The first thing I noticed was that there is plenty to replace beneath the preset button and coil assemblies, so the wires were labelled and desoldered. I had hoped that the two parts could stay soldered together, but there was another connection to the coil frame that was beneath the whole thing. So 12 wires were dutifully desoldered, and then the two parts could be out of the way. This is safer overall, as the preset coils have very vulnerable fine wires.
I cut a circle of cardboard and covered the speaker, also drew out a diagram of the chassis, and checked off which valve locates in each socket.
The three electrolytics were removed from the chassis. I think I will restuff these, and remove the parts added beneath. The wiring looks to be clear enough - remember, I have no documentation to go on whatsoever.
The transformers were checked for continuity, and all test well, also the speaker field coil. The mains switch was cleaned, and with all valves removed, power was applied using the "dim bulb" tester. Not a flicker from the bulb, but the dial lights lit up, and all secondary voltages seemed in order. There's a good 350V AC on each half of the HT winding, so they meant business, feeding the two #41 output valves.
The tuning drive string broke, I've ordered some new cord. The mechanism confused me at first, there are two strings - one connecting the drum to the tuning shaft, the other connecting to the dial mechanism.
Lastly, I tested removal of the rust. It seems this might well clean up better than expected so gentle scrubbing with a kitchen scourer, plus rust removal gel will be pursued first.
Cheers
Ed
I don't hold with furniture that talks.
