02-06-2023, 10:38 AM
Thanks John and Chas, a lot to digest here for sure! To answer your question John, yes this is the only TRF I’ve ever worked on or even listened to so I have no idea of what to expect as far as performance. My set uses all 01As except for the 200 detector. I have swapped in an 01A for the detector with not much difference. My phone line conversion to use as a long wire antenna works really well on my long wire superhet sets.
Chas, I didn’t realize these tubes/sets are that finicky as far as the “A” supply goes. I am using a computer ps that puts out 5V. I changed from a no name ps to a Dell with same voltages. The first supply I used turned out to be noisy, the Dell is much quieter. I’m going to see what I can rig up to get an honest 6-6.5V. That resistance wire in the AF filament supply was crumbling so I replaced it with a .47 ohm carbon resistor which measured close to what the wire does. I’ve tried using my signal generator by going stage by stage connecting it through a cap. Then I used a coil with several turns wound on a TP roll that fits quite well over these tubes. With the quieter ps now I can get hear 2 stations, probably 3 at night but it is alive mostly in the middle of the band, the upper and lower ends are dead. I’ve tried the AK synchronization method plus randomly experimenting.
John, I will experiment with that cap and grid resistor on the detector and see what changes occur. I have changed the B+ value up and down on the detector plate supply without much difference. So, I have lots of things to further look into and I appreciate you and Chas for all your input. OBTW, congrats John on your upcoming retirement. You obviously have antique radios as a hobby like me but in fair weather, I have my hiking and outdoor activities. Hobbies are a must otherwise you’ll be bored and go nuts, daytime TV is a wasteland! Now get yourself healed.
Ron
Chas, I didn’t realize these tubes/sets are that finicky as far as the “A” supply goes. I am using a computer ps that puts out 5V. I changed from a no name ps to a Dell with same voltages. The first supply I used turned out to be noisy, the Dell is much quieter. I’m going to see what I can rig up to get an honest 6-6.5V. That resistance wire in the AF filament supply was crumbling so I replaced it with a .47 ohm carbon resistor which measured close to what the wire does. I’ve tried using my signal generator by going stage by stage connecting it through a cap. Then I used a coil with several turns wound on a TP roll that fits quite well over these tubes. With the quieter ps now I can get hear 2 stations, probably 3 at night but it is alive mostly in the middle of the band, the upper and lower ends are dead. I’ve tried the AK synchronization method plus randomly experimenting.
John, I will experiment with that cap and grid resistor on the detector and see what changes occur. I have changed the B+ value up and down on the detector plate supply without much difference. So, I have lots of things to further look into and I appreciate you and Chas for all your input. OBTW, congrats John on your upcoming retirement. You obviously have antique radios as a hobby like me but in fair weather, I have my hiking and outdoor activities. Hobbies are a must otherwise you’ll be bored and go nuts, daytime TV is a wasteland! Now get yourself healed.
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84