05-18-2020, 12:13 PM
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I tried 4 different value chokes in place of shortwave/broadcast coil #28. In every instance I checked both push button and manual dialing. I have set my SG to 910 Kc and I have tuned the radio to that same frequency because that is the broadcast frequency of a 1000 Watt local and it's mid point on the dial. My presumption being if I manage to get the oscillator working I will hear the generator at least strong enough that I could peak any trimmers. I have the SG tied to antenna lead marked white-green, no other antenna attached.
HV in your response confuses me a bit, “hv lead and the bottom of #28,” I have already tied a current meter set to MA in series with #28, attached to pin # 3, 7J7 and terminal 3 of #28. There was no current drop. I tried 2 different meters to make sure I was getting an accurate measurement and clip were attached correctly. Meter will produce voltage readings but 0 current.
The HV is the inside winding. They used a cardboard tube, around which is the HV winding. They then put that tube inside a second tube and created the SW winding around the outside. The whole thing is encased in wax. The HV break was the connection inside of that inner cardboard tube. Hair-like wire was brittle and easily broke. I finally heavily solder tinned a chunk of copper solder wick. I put that physically inside of the tube with the lead laying on top and using a pencil iron I heated that solder and pressed the winding into it. I have continuity but I have no idea where I picked up that winding. Was the short piece of wire I found the end of that winding? No idea.
Chokes I've substituted for shortwave/broadcast coil #28: 10uH, 47uH, 100uH, (slug tuned) 2.2 HM, (slug tuned) and the oscillator coil I got from Tubes and More. Last night I tried that Tubes and More coil in place of the existing broadcast oscillator coil. I have tested that coil for continuity and it matches the specifications on the print, but I had never tried to sub it out before.
Thanks guys, I really appreciate the help.
Tom
I tried 4 different value chokes in place of shortwave/broadcast coil #28. In every instance I checked both push button and manual dialing. I have set my SG to 910 Kc and I have tuned the radio to that same frequency because that is the broadcast frequency of a 1000 Watt local and it's mid point on the dial. My presumption being if I manage to get the oscillator working I will hear the generator at least strong enough that I could peak any trimmers. I have the SG tied to antenna lead marked white-green, no other antenna attached.
HV in your response confuses me a bit, “hv lead and the bottom of #28,” I have already tied a current meter set to MA in series with #28, attached to pin # 3, 7J7 and terminal 3 of #28. There was no current drop. I tried 2 different meters to make sure I was getting an accurate measurement and clip were attached correctly. Meter will produce voltage readings but 0 current.
The HV is the inside winding. They used a cardboard tube, around which is the HV winding. They then put that tube inside a second tube and created the SW winding around the outside. The whole thing is encased in wax. The HV break was the connection inside of that inner cardboard tube. Hair-like wire was brittle and easily broke. I finally heavily solder tinned a chunk of copper solder wick. I put that physically inside of the tube with the lead laying on top and using a pencil iron I heated that solder and pressed the winding into it. I have continuity but I have no idea where I picked up that winding. Was the short piece of wire I found the end of that winding? No idea.
Chokes I've substituted for shortwave/broadcast coil #28: 10uH, 47uH, 100uH, (slug tuned) 2.2 HM, (slug tuned) and the oscillator coil I got from Tubes and More. Last night I tried that Tubes and More coil in place of the existing broadcast oscillator coil. I have tested that coil for continuity and it matches the specifications on the print, but I had never tried to sub it out before.
Thanks guys, I really appreciate the help.
Tom
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