16-04-2016, 11:14 PM
Not quite so quick, but .....
I've been keeping an eye out for one of these for some time but they seem quite 'Desirable' and/or a long way away. This one was a good Price and could be Posted, so give it a go.
They come in two Flavours - the P115U which is Permeability Tuned and the P116U which has a conventional Tuning Capacitor. They appear to have been available in Parallel although I haven't a clue why. They're mid '50s so I can't imagine it was Component shortages. The Cabinet is thin bent Ply with a Plastic Front. Both have a PCB and are AC/DC with B8A U Series Valves - a bit unusual for Pye.
It arrived safe and sound and had a gratifying layer of Dust and no obvious bodges. Even the 2-Core Mains Lead was connected the right way round and the Plug had a 3A Fuse.
On firing it up it was dead, but some Switch Cleaner in the Valve Holders cheered it up no end. The Volume Pot was very crackly but again a blast of Cleaner sorted it. It wasn't very sensitive so remove the Chassis and Speaker and see what the score was with the components. Having dusted it off it was easy to see that it was riddled with dodgy-looking Capacitors and any Resistor above 100k was way out. Also, there were a couple of other lower Values, particularly the Output Valve Cathode Resistor which were too far out to leave.
Step one was to change the dodgy Capacitors. The Electrolytics were OK. Oddly, although it has a PCB it isn't easy to work on as the Top is not easy to get at. That cheered it up no end, so on with the Resistors. Again, apart from access it was all pretty straightforward. However, on switching on it was back to being pretty dead - just faint sounds from the Speaker. The obvious question was 'What have I done?' Careful examination of the PCB showed no obvious breaks, shorts or Dry Joints. However, the Voltages around the Output Valve were all over the place. After a bit oh Head-scratching it dawned on me that I'd but the UBC41 and UL41 in the wrong Bases - Doh. Putting them back in the right places fixed the Voltages and it sprang to life. In fact it's quite sensitive as this range of Valves tend to be, despite the Frame Aerial.
A clean up of the Cabinet and the knobs, and reassembly more or less finished the Job. One oddity is that out on the Bench it sounds quite Tinny but back in the Cabinet it sounds quite good. The Cabinet would probably benefit from re-varnishing as the Top is quite worn, but it's really just age and Heat.
There's no Slow-motion, just a big Knob, but it works well enough for a 'Second Set'. I'm not sure where it's going to finish up yet, either the Garage or the Greenhouse. We'll see.
Alan
I've been keeping an eye out for one of these for some time but they seem quite 'Desirable' and/or a long way away. This one was a good Price and could be Posted, so give it a go.
They come in two Flavours - the P115U which is Permeability Tuned and the P116U which has a conventional Tuning Capacitor. They appear to have been available in Parallel although I haven't a clue why. They're mid '50s so I can't imagine it was Component shortages. The Cabinet is thin bent Ply with a Plastic Front. Both have a PCB and are AC/DC with B8A U Series Valves - a bit unusual for Pye.
It arrived safe and sound and had a gratifying layer of Dust and no obvious bodges. Even the 2-Core Mains Lead was connected the right way round and the Plug had a 3A Fuse.
On firing it up it was dead, but some Switch Cleaner in the Valve Holders cheered it up no end. The Volume Pot was very crackly but again a blast of Cleaner sorted it. It wasn't very sensitive so remove the Chassis and Speaker and see what the score was with the components. Having dusted it off it was easy to see that it was riddled with dodgy-looking Capacitors and any Resistor above 100k was way out. Also, there were a couple of other lower Values, particularly the Output Valve Cathode Resistor which were too far out to leave.
Step one was to change the dodgy Capacitors. The Electrolytics were OK. Oddly, although it has a PCB it isn't easy to work on as the Top is not easy to get at. That cheered it up no end, so on with the Resistors. Again, apart from access it was all pretty straightforward. However, on switching on it was back to being pretty dead - just faint sounds from the Speaker. The obvious question was 'What have I done?' Careful examination of the PCB showed no obvious breaks, shorts or Dry Joints. However, the Voltages around the Output Valve were all over the place. After a bit oh Head-scratching it dawned on me that I'd but the UBC41 and UL41 in the wrong Bases - Doh. Putting them back in the right places fixed the Voltages and it sprang to life. In fact it's quite sensitive as this range of Valves tend to be, despite the Frame Aerial.
A clean up of the Cabinet and the knobs, and reassembly more or less finished the Job. One oddity is that out on the Bench it sounds quite Tinny but back in the Cabinet it sounds quite good. The Cabinet would probably benefit from re-varnishing as the Top is quite worn, but it's really just age and Heat.
There's no Slow-motion, just a big Knob, but it works well enough for a 'Second Set'. I'm not sure where it's going to finish up yet, either the Garage or the Greenhouse. We'll see.
Alan