09-24-2022, 08:09 PM
Hi Keefer,
One other thing:
Does this radio have a 0Z4 rectifier or a rectifier with a filament / cathode? If it has a 0Z4, consider replacing it with a 6X5. The 6X5 was designed with car radios in mind, although Philco and Zenith used it quite often for home radios. Check to see of the rectifier socket is wired for it. The pinouts are supposed to be the same, except that the 0Z4 does not use pins 2 and 7 because, being a gas discharge rectifier, it does not have a filament / heater. Some radios are wired to use either tube. Adding the filament wiring will allow either tube. Having the wiring will not affect the use of a 0Z4 tube if desired.
Another possible alternative is to replace the 0Z4 with 3A 1000PRV diodes. It may be prudent to put resistors in the anode leads between the transformer and the diodes (maybe 1K Ohm, 2W. However, the voltage out of the solid state rectifier will be higher than with either tube. Consider filter caps that are 400 or 450 WV.
The issue with the 0Z4 is the voltage / current required to "start" it (for the gas to ionize). I have heard the frequency of the solid state vibrator may be lower than that of a mechanical vibrator. Maybe a lower frequency is preventing the triggering of the tube. Dunno why leaning it on the side will cause the 0Z4 to fire. If you measure "Plate to Plate" AC voltage at the rectifier when the radio is not playing, is it the same or higher as the voltage when the radio is not playing?
Does the manufacturer of the solid state vibrator instruct you to remove the buffer cap? If not, it may be a good idea to have that in place. The vibrator (either mechanical or solid state) does not exactly produce a sine wave; it is more like a square wave, and I wonder if more like car ignition.
One other thing:
Does this radio have a 0Z4 rectifier or a rectifier with a filament / cathode? If it has a 0Z4, consider replacing it with a 6X5. The 6X5 was designed with car radios in mind, although Philco and Zenith used it quite often for home radios. Check to see of the rectifier socket is wired for it. The pinouts are supposed to be the same, except that the 0Z4 does not use pins 2 and 7 because, being a gas discharge rectifier, it does not have a filament / heater. Some radios are wired to use either tube. Adding the filament wiring will allow either tube. Having the wiring will not affect the use of a 0Z4 tube if desired.
Another possible alternative is to replace the 0Z4 with 3A 1000PRV diodes. It may be prudent to put resistors in the anode leads between the transformer and the diodes (maybe 1K Ohm, 2W. However, the voltage out of the solid state rectifier will be higher than with either tube. Consider filter caps that are 400 or 450 WV.
The issue with the 0Z4 is the voltage / current required to "start" it (for the gas to ionize). I have heard the frequency of the solid state vibrator may be lower than that of a mechanical vibrator. Maybe a lower frequency is preventing the triggering of the tube. Dunno why leaning it on the side will cause the 0Z4 to fire. If you measure "Plate to Plate" AC voltage at the rectifier when the radio is not playing, is it the same or higher as the voltage when the radio is not playing?
Does the manufacturer of the solid state vibrator instruct you to remove the buffer cap? If not, it may be a good idea to have that in place. The vibrator (either mechanical or solid state) does not exactly produce a sine wave; it is more like a square wave, and I wonder if more like car ignition.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
Best Regards,
MrFixr55