11-27-2017, 04:21 PM
jcassity;
Yes the unit I am working on is Run 3 with a 7AF7 RF tube in the front end.
I was lucky that I was able to fish out the end of the wire the mice had chewed apart and by careful re-tinning of the lead I established continuity again, then used a very fine insulated wire from one of the very small audio cables often seen used for connection to phonograph cartridge connections. It is about 28AWG stranded wire with a white insulation cover. That matches with the white wire coming up to the solder lug on the bottom of the transformer. I used the smallest size of white heat-shrink tubing to protect the completed connection and shrunk that, then added a couple of small drops of clear plastic glue to stabilize the end of the wire at the winding of the transformer.
I turned on the radio again and tuned across the dial and began to pick up stations with my finger serving as an antenna - success! I had been on line looking at Philco radios and spotted a 46-1226 chassis complete with tubes for $25 plus a little over $21 for shipping. However, since I managed to repair this transformer I will not have to do anything that drastic to complete the restoration.
When I was changing the old wax paper-foil capacitors I spent hours tracing the other components and wires attached to them and studying the schematic versions to verify each circuit. It was a good thing, as it kept me from connecting some parts incorrectly as I replaced parts. I did get myself in a problem with one circuit where I stopped overnight without finishing one reconnect. I had to remove one connection and re-solder the parts to correct my error the next morning. Hand wired chassis are often somewhat of a rat's nest and can be confusing to work on. This one is no exception.
Yes I have had to use two schematic versions to work on this set. I was lucky that the tube tester I have had a supplemental booklet that showed the settings for testing the 7AF7 tube. In fact the roll-chart of my tube tester had only about two 7xx type tubes listed on it. All the others are in the supplement. This is my oldest tester (an Allied Radio unit) which has the sockets needed for the old 4 pin, 5 pin tubes seen in radios from the late 1920s and into the 1930s. My other tube tester does not have the Loctal type sockets and so does not cover the 7xx tubes at all, but it will check tubes such as the 7868 tubes used in late model Fisher tube type stereos.
Joe
Yes the unit I am working on is Run 3 with a 7AF7 RF tube in the front end.
I was lucky that I was able to fish out the end of the wire the mice had chewed apart and by careful re-tinning of the lead I established continuity again, then used a very fine insulated wire from one of the very small audio cables often seen used for connection to phonograph cartridge connections. It is about 28AWG stranded wire with a white insulation cover. That matches with the white wire coming up to the solder lug on the bottom of the transformer. I used the smallest size of white heat-shrink tubing to protect the completed connection and shrunk that, then added a couple of small drops of clear plastic glue to stabilize the end of the wire at the winding of the transformer.
I turned on the radio again and tuned across the dial and began to pick up stations with my finger serving as an antenna - success! I had been on line looking at Philco radios and spotted a 46-1226 chassis complete with tubes for $25 plus a little over $21 for shipping. However, since I managed to repair this transformer I will not have to do anything that drastic to complete the restoration.
When I was changing the old wax paper-foil capacitors I spent hours tracing the other components and wires attached to them and studying the schematic versions to verify each circuit. It was a good thing, as it kept me from connecting some parts incorrectly as I replaced parts. I did get myself in a problem with one circuit where I stopped overnight without finishing one reconnect. I had to remove one connection and re-solder the parts to correct my error the next morning. Hand wired chassis are often somewhat of a rat's nest and can be confusing to work on. This one is no exception.
Yes I have had to use two schematic versions to work on this set. I was lucky that the tube tester I have had a supplemental booklet that showed the settings for testing the 7AF7 tube. In fact the roll-chart of my tube tester had only about two 7xx type tubes listed on it. All the others are in the supplement. This is my oldest tester (an Allied Radio unit) which has the sockets needed for the old 4 pin, 5 pin tubes seen in radios from the late 1920s and into the 1930s. My other tube tester does not have the Loctal type sockets and so does not cover the 7xx tubes at all, but it will check tubes such as the 7868 tubes used in late model Fisher tube type stereos.
Joe
