03-12-2024, 06:30 PM
Hi all,
Not sure what happened to my original post. Bits and pieces were missing.
As I mentioned in past posts I am trying to learn this hobby slowly. I have a 40-120 philco I have been tinkering with for a couple of months now. I also bought 2 more off of eBay, one of which is in working order. My goal was to take the schematic and study the way everything is connected while slowly re-wiring the one I had. I managed to overcome several hiccups with bad RF coil and broken domino capacitor lead. I have the original radio, I started with, wired identical, from what I can tell, to the radio that works perfectly.
All of the original wax tubular capacitors have been replaced with brand new capacitors from Antique Radio Supply that are equal in microfarads as well as voltages. If the voltage size was not available I chose the next size up, never lower. All resistors were replaced with brand new resistors of the exact Ohms and wattage. I have tested all the new capacitors to make sure their capacitance is still true and so far all the new caps have been reading very close to spot on. The only resistors that haven't been replaced are number 34 which is the long filament resistor and it reads correctly. Also number 27 which is a 130 ohm, 1/2 watt resistor connected on the bottom of the 35A5 tube. It tests as 135 ohms.
I am at the point of power on which I have done with a Variac and my Cristy A2 dim bulb tester. Pilot light comes on slightly bright and then dims as the tubes warm up. All I hear is the exact same sound as when you have a bad filter cap. The volume control does work at decreasing and increasing the volume of the hum. I have checked the new electrolytic cap for microfarads, correct polarity, and basic leakage with the Cristy A2 Tester which can also test for leakage. Both sides are perfect. All other capacitors, which are all brand new from Antique Radio Supply, test correct as well. I have swapped out the tubes with the set that works perfect into the set I am working with and get the same result.
I have been busy watching Mr. Carlson and Glasslinger on YouTube for ideas. So far the closest thing I have seen is a video about a Ground loop, but I cannot find anything like that.
What might my next step be? If someone could give me an idea on what to check next it would be much appreciated.
Not sure what happened to my original post. Bits and pieces were missing.
As I mentioned in past posts I am trying to learn this hobby slowly. I have a 40-120 philco I have been tinkering with for a couple of months now. I also bought 2 more off of eBay, one of which is in working order. My goal was to take the schematic and study the way everything is connected while slowly re-wiring the one I had. I managed to overcome several hiccups with bad RF coil and broken domino capacitor lead. I have the original radio, I started with, wired identical, from what I can tell, to the radio that works perfectly.
All of the original wax tubular capacitors have been replaced with brand new capacitors from Antique Radio Supply that are equal in microfarads as well as voltages. If the voltage size was not available I chose the next size up, never lower. All resistors were replaced with brand new resistors of the exact Ohms and wattage. I have tested all the new capacitors to make sure their capacitance is still true and so far all the new caps have been reading very close to spot on. The only resistors that haven't been replaced are number 34 which is the long filament resistor and it reads correctly. Also number 27 which is a 130 ohm, 1/2 watt resistor connected on the bottom of the 35A5 tube. It tests as 135 ohms.
I am at the point of power on which I have done with a Variac and my Cristy A2 dim bulb tester. Pilot light comes on slightly bright and then dims as the tubes warm up. All I hear is the exact same sound as when you have a bad filter cap. The volume control does work at decreasing and increasing the volume of the hum. I have checked the new electrolytic cap for microfarads, correct polarity, and basic leakage with the Cristy A2 Tester which can also test for leakage. Both sides are perfect. All other capacitors, which are all brand new from Antique Radio Supply, test correct as well. I have swapped out the tubes with the set that works perfect into the set I am working with and get the same result.
I have been busy watching Mr. Carlson and Glasslinger on YouTube for ideas. So far the closest thing I have seen is a video about a Ground loop, but I cannot find anything like that.
What might my next step be? If someone could give me an idea on what to check next it would be much appreciated.
