06-13-2025, 06:50 PM
Hi Arran.
I continue to disassemble and I see that the interstage transformer is completely beyond repair. It is placed in an iron box and completely filled with bitumen. There is no way to clean and rewind it. But I plan to use for the first step the circuit upgrade we discussed above with a symmetrical choke instead of a phase inverter transformer. As a choke I plan to use a small 120-240V converter transformer, I have a couple of them, it should be popular for this purpose. In the future, I may find a ready-made transformer with a combination of about 120V + 120V + 120V or something like that. I can apply a similar method to the output transformer. I have changed similar parts several times to fix the problem of a broken output transformer in several of my portable tube radios. In this case, rewinding is extremely difficult, as the audio transformer in this radio is very small and has a huge number of turns of very thin wire. For this case, I used with good results a 120v x 6-12v power transformer from an old power supply from small devices such as a phone charger. The winding data for this transformer matched the original requirements quite closely.
I continue to disassemble and I see that the interstage transformer is completely beyond repair. It is placed in an iron box and completely filled with bitumen. There is no way to clean and rewind it. But I plan to use for the first step the circuit upgrade we discussed above with a symmetrical choke instead of a phase inverter transformer. As a choke I plan to use a small 120-240V converter transformer, I have a couple of them, it should be popular for this purpose. In the future, I may find a ready-made transformer with a combination of about 120V + 120V + 120V or something like that. I can apply a similar method to the output transformer. I have changed similar parts several times to fix the problem of a broken output transformer in several of my portable tube radios. In this case, rewinding is extremely difficult, as the audio transformer in this radio is very small and has a huge number of turns of very thin wire. For this case, I used with good results a 120v x 6-12v power transformer from an old power supply from small devices such as a phone charger. The winding data for this transformer matched the original requirements quite closely.
If you want to work, lie down and sleep, and everything will pass.
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