05-30-2013, 10:10 PM
OK, so:
http://www.nostalgiaair.org/PagesByModel...013199.pdf
1. The radio was at some point...repaired. The reason was obvious, the electrolytic caps. Judging by the parts it was done long time ago.
The caps 126 and 127 (I extracted them) weigh very little and they are supposed to be heavy. Bone-dry inside. One of them foamed. And according to the sch they are 8uF each, but the real ones are 4uF each. And the guy replaced them with one old tubular 10uF cap (they are paralleled).
Surprisingly the replacement cap which is probably over 30 years old is still 9.7uF. It was paralleled to that cap that foamed; another one was cut off.
2. Big surprise: The Candohm 4K+1K is alive and is indeed 3.9K + 1.0K, nice!
3. The output tubes' wiring seems to be factory, the pins 1 and 8 (one is NC and 8 is Cathode) grounded. And the transformer filament windings (both) that are supposed to be grounded via centertapped 60 Ohm resistors are not. So I take it this is the version with 6A5 tubes and not 6B4.
4. Some tubular caps are there, some seem to be original and some are added to probably fix some backelites.
5. The backelites were not rebuilt.
6. The backelites have their rivets flooded with solder. Some look like they were touched up. But the internal wires (that I am supposed to cut when rebuilding) are all soldered to the rivets; will complicate the process somewhat.
Well, not all is bad.
In 2-3 weeks I will get those 5C4S rectifier tubes (5U4), new unused Soviet production, plus some 6S2S (6J5) - it's a gift and the one that comes handy at that.
The underbelly is clean and with exception of one small cobweb does not need cleaning at all.
http://www.nostalgiaair.org/PagesByModel...013199.pdf
1. The radio was at some point...repaired. The reason was obvious, the electrolytic caps. Judging by the parts it was done long time ago.
The caps 126 and 127 (I extracted them) weigh very little and they are supposed to be heavy. Bone-dry inside. One of them foamed. And according to the sch they are 8uF each, but the real ones are 4uF each. And the guy replaced them with one old tubular 10uF cap (they are paralleled).
Surprisingly the replacement cap which is probably over 30 years old is still 9.7uF. It was paralleled to that cap that foamed; another one was cut off.
2. Big surprise: The Candohm 4K+1K is alive and is indeed 3.9K + 1.0K, nice!
3. The output tubes' wiring seems to be factory, the pins 1 and 8 (one is NC and 8 is Cathode) grounded. And the transformer filament windings (both) that are supposed to be grounded via centertapped 60 Ohm resistors are not. So I take it this is the version with 6A5 tubes and not 6B4.
4. Some tubular caps are there, some seem to be original and some are added to probably fix some backelites.
5. The backelites were not rebuilt.
6. The backelites have their rivets flooded with solder. Some look like they were touched up. But the internal wires (that I am supposed to cut when rebuilding) are all soldered to the rivets; will complicate the process somewhat.
Well, not all is bad.
In 2-3 weeks I will get those 5C4S rectifier tubes (5U4), new unused Soviet production, plus some 6S2S (6J5) - it's a gift and the one that comes handy at that.
The underbelly is clean and with exception of one small cobweb does not need cleaning at all.