March 18, 2020 at 6:11 pm #13426
Has anyone used one of these?
I’m having no luck finding a 5Y4G close to home. This will work if you move the pin locations to suit a 5Y3GMarch 19, 2020 at 5:26 am #13429Alistair ThomsonCVRS Member
When I was a kid I had an RME69 communications receiver. The rectifier tube had died on me and, knowing something about electronics back then (but not a lot), I removed the glass envelope and wired a pair of 1N4007 diodes in to the exposed base pins.
It worked beautifully for about five minutes, then all the electrolytics blew up. That was the bit I hadn’t known! It was good to see in your advert that the suppliers warn users about that!March 19, 2020 at 7:28 am #13431Jean MarcotteForum Participant
I replaced a 6X4 that had a cathode to filament short in my german radio by 1N4007 diodes. I also had to replace the power transformer and some components around it because it caught fire… I used two 1N4007 in series for each side with a resistor in series with the output to lower the output voltage and limit the initial current. If you don’t have that resistor, the voltage on your caps rises instantly to a much higher value when you put the power on.The two diodes in series is just an insurance policy in case one breaks down. If I remeber well the resistance was around 100 ohms 5w.March 19, 2020 at 8:56 am #13434Les DicksonCVRS Member
I replaced an 80 in much the same way as Jean Marcotte, with two diodes in series and some hefty resistors. I had to experiment to get the correct resistance. I also added a thermistor to the power supply to bring up the voltages slowly.March 19, 2020 at 10:13 am #13435
Can a thermistor be wired in with the original rectifier 5Y4G in place? Can they be used in AA5 radios? I hate the way the little Emerson I have spikes on start up. I imagine it’s pretty hard on everything.March 20, 2020 at 8:26 pm #13491
Many thanks Jean Marcotte!!!
Jean was kind enough to find me a 5Y4G in order to advance the repair/troubleshooting on the Philco 38-04 radio AND dropped it off at my place!!! Radio now plays quite well, but needs a volume pot and also an on/off 4 tone switch. perhaps it’s sacrilege to move stuff around, but I thought to yank the 4 tone on off switch (far left) and replace it with a conventional on/off volume switch, then install the 4 tone switch where the volume switch (far right) was. Only the on off is buggered, the 4 position tone part works great. This is a more conventional set up and solves the problem of finding a on/off 4 position tone switch. I have not looked for a on/off vol switch with the long shaft required for these radios. Is one place cheaper/better than another for that type of part?
Gary in Montreal
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