07-31-2015, 07:19 PM
Warren - That is a nice record to have! i started getting into the big bands and early jazz once I started working on/collecting tube radios. I wanted to hear what they would have sounded like playing the music from that era. And suddenly i found my self enjoying it. 10 years ago i would have called myself crazy...
Terry - I replaced all resistors when I refurbed the radio. R31 is reading 3.98M and R32 is 69.7k. Both spot on. I also replaced all mica's, so C34 is brand new. I did check voltages way back when i first powered it on, but can't find the numbers. But i do recall them all looking fairly good. But I rechecked them.
Below is what I read, and in parentheses is what the schematic/service notes say (a few are hard to read, those have ? marks). I had the variac on 115 to start, but it drifted down to 114 by the time I was done. Radio was on BC and tuned to my SSTRAN (the service notes didn't say if it should be tuned to a station or not), but with the volume all the way down. All readings VDC and to chassis, except where noted.
C43 - First filter
Pos to CT: 318.2 (325)
CT to Chassis: 14.88 (15)
C18 - Second filter
209.8 (215?)
C17
184.6 (190?)
84 Rectifier
Cathode: 303.9 (310)
6A8 Det/Osc
3 Plate: 209.8 (215)
4 Screen: 77.8 (80)
5 Osc Grid: -26.6 (n/a)
6 Osc Anode: 161.9 (175)
78 IF
2 Plate: 210.7 (215)
3 Screen: 78.0 (80)
4 Suppressor: -2.88 (n/a)
37 2nd Det/AVC
2 Plate: -5.11 (n/a)
3 Grid: -4.38 (n/a)
75 1st Audio
2 Plate: 143.1 (135?)
3 &4 Diodes (tied together): -5.69 (n/a)
41 Output
2 Plate: 203.8 (205)
3 Screen: 213.9 (215)
4 Grid: -14.02 (n/a)
Over all, nothing is jumping out at me as blatantly wrong. B+ is a touch low - about 5 to 6v, but that shouldn't matter much. The 75 plate is a little high, but I suspect that is because the DMM isn't loading the circuit. The only other reading that is off is the osc. anode/"plate" that is about 13v low.
Terry - I replaced all resistors when I refurbed the radio. R31 is reading 3.98M and R32 is 69.7k. Both spot on. I also replaced all mica's, so C34 is brand new. I did check voltages way back when i first powered it on, but can't find the numbers. But i do recall them all looking fairly good. But I rechecked them.
Below is what I read, and in parentheses is what the schematic/service notes say (a few are hard to read, those have ? marks). I had the variac on 115 to start, but it drifted down to 114 by the time I was done. Radio was on BC and tuned to my SSTRAN (the service notes didn't say if it should be tuned to a station or not), but with the volume all the way down. All readings VDC and to chassis, except where noted.
C43 - First filter
Pos to CT: 318.2 (325)
CT to Chassis: 14.88 (15)
C18 - Second filter
209.8 (215?)
C17
184.6 (190?)
84 Rectifier
Cathode: 303.9 (310)
6A8 Det/Osc
3 Plate: 209.8 (215)
4 Screen: 77.8 (80)
5 Osc Grid: -26.6 (n/a)
6 Osc Anode: 161.9 (175)
78 IF
2 Plate: 210.7 (215)
3 Screen: 78.0 (80)
4 Suppressor: -2.88 (n/a)
37 2nd Det/AVC
2 Plate: -5.11 (n/a)
3 Grid: -4.38 (n/a)
75 1st Audio
2 Plate: 143.1 (135?)
3 &4 Diodes (tied together): -5.69 (n/a)
41 Output
2 Plate: 203.8 (205)
3 Screen: 213.9 (215)
4 Grid: -14.02 (n/a)
Over all, nothing is jumping out at me as blatantly wrong. B+ is a touch low - about 5 to 6v, but that shouldn't matter much. The 75 plate is a little high, but I suspect that is because the DMM isn't loading the circuit. The only other reading that is off is the osc. anode/"plate" that is about 13v low.
