10 hours ago
Hi Phil,
Don't worry, no need to apologize. It takes me forever to do a post and then go back after interruptions caused by life, and then update after I note my mistakes. Please do feel free to read that post only when you are ready to do the electrolytics. I posted now, not to dump more stuff on you for you to worry about, but to make sure that I documented what I thought was important.
What you may be seeing is new resistors being put in parallel with old resistors whose values have changed. the original resistors of the 1930s, sometimes referred to as "dogbone" resistors are very much prone to increasing in value. this radio was likely 10 years old by the middle of WWII. Unlike modern electronics which rarely require service and are unfortunately discarded as unrepairable, these sets represented a major investment by the owner. By the time that they are 8-15 years old, they would have required service. During WWII, from 1942 till 1946, there was no new consumer electronics, and even tubes and repair parts were scarce. Therefore, putting another resister in parallel to bring the errant resistor back into spec was common. then by the time that new electronics was available or the radio broke enough times, it found itself at the curb or in a landfill where preteen or early teen boys, and occasionally girls) like me picked them up as their first electronic projects, usually resulting in such butchery as you are noting in your set.
The best way of dealing with this is replacing the dogbone resistors and even the 1940-s- 1970s style resistors with new metal film resistors. Signal resistors can be 1/2 w. But any resistors in "voltage dividers should be of higher wattage.
Regarding the bakelite blocks, there are 2 ways of handling them. Either scooping out the contents and replacing them with modern caps. This can be done without disconnecting the external connections; see Morzh's post in the Library under Techniques. A link is attached here:
https://philcoradio.com/library/index.ph...soldering/
The other way is to just pass a drill through the rivets to cut the wires connecting the internal components to the external terminals. Thie is quick but dirty, and Morzh's technique is rather quick, and results in a clean, factory-like result.
Any paper caps, "black beauty" or "bumble bee" caps or ceramic coated tubular caps should be replaced as they leak or short. You likely do not have many of these. It appears that the dark brown caps that are clustered in one area are likely mylar. If installed correctly, they can remain. As stated before, by many experts in many posts, any electrolytic must go if not recently replaced. It is likely that all electrolytics are either original (Cap # 73) or are replacements (the Tobe cap and the blue electrolytic by R90). These must go!
Good luck, keep asking, please never worry about asking us to clarify our posts. Keep plugging and you will be rewarded with a nice, historically important radio. Just think that the owner was listening to shortwave to find out what was happing in their ancestorial country, praying while listening to Vatican Radio or feeling anxious, listening to news of a world descending to war. Remember, radio, especially shortwave was the internet of the 1930s and 1940s
Don't worry, no need to apologize. It takes me forever to do a post and then go back after interruptions caused by life, and then update after I note my mistakes. Please do feel free to read that post only when you are ready to do the electrolytics. I posted now, not to dump more stuff on you for you to worry about, but to make sure that I documented what I thought was important.
What you may be seeing is new resistors being put in parallel with old resistors whose values have changed. the original resistors of the 1930s, sometimes referred to as "dogbone" resistors are very much prone to increasing in value. this radio was likely 10 years old by the middle of WWII. Unlike modern electronics which rarely require service and are unfortunately discarded as unrepairable, these sets represented a major investment by the owner. By the time that they are 8-15 years old, they would have required service. During WWII, from 1942 till 1946, there was no new consumer electronics, and even tubes and repair parts were scarce. Therefore, putting another resister in parallel to bring the errant resistor back into spec was common. then by the time that new electronics was available or the radio broke enough times, it found itself at the curb or in a landfill where preteen or early teen boys, and occasionally girls) like me picked them up as their first electronic projects, usually resulting in such butchery as you are noting in your set.
The best way of dealing with this is replacing the dogbone resistors and even the 1940-s- 1970s style resistors with new metal film resistors. Signal resistors can be 1/2 w. But any resistors in "voltage dividers should be of higher wattage.
Regarding the bakelite blocks, there are 2 ways of handling them. Either scooping out the contents and replacing them with modern caps. This can be done without disconnecting the external connections; see Morzh's post in the Library under Techniques. A link is attached here:
https://philcoradio.com/library/index.ph...soldering/
The other way is to just pass a drill through the rivets to cut the wires connecting the internal components to the external terminals. Thie is quick but dirty, and Morzh's technique is rather quick, and results in a clean, factory-like result.
Any paper caps, "black beauty" or "bumble bee" caps or ceramic coated tubular caps should be replaced as they leak or short. You likely do not have many of these. It appears that the dark brown caps that are clustered in one area are likely mylar. If installed correctly, they can remain. As stated before, by many experts in many posts, any electrolytic must go if not recently replaced. It is likely that all electrolytics are either original (Cap # 73) or are replacements (the Tobe cap and the blue electrolytic by R90). These must go!
Good luck, keep asking, please never worry about asking us to clarify our posts. Keep plugging and you will be rewarded with a nice, historically important radio. Just think that the owner was listening to shortwave to find out what was happing in their ancestorial country, praying while listening to Vatican Radio or feeling anxious, listening to news of a world descending to war. Remember, radio, especially shortwave was the internet of the 1930s and 1940s
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Best Regards,
MrFixr55