01-03-2014, 01:56 PM
If you can find an original equipment type that is by far the easiest way to go. Of course if you have no way to verify it is good, it could turn into a can of worms. Make sure any such item has been checked at least by ohm meter to make sure the primary and secondary windings are good and have no shorts to the transformer case.
I did some checking against the schematic for your radio and I see these parameters about the power the transformer has to supply:
The B+ at the first electrolytic (item 61 ) is 270VDC and at the second electrolytic (item 58 ) is 185VDC. The field coil of the speaker serves as a choke and its resistance is 1100 ohms. There is an 85VDC drop across the field coil which means that the entire B+ load of the radio is drawing about 77.2 milliamps so round that up to 80 milliamps and that is the approximate power being delivered by the B+ circuits. The total amps of the filaments is about 2.35 amps if you allow for a couple of dial lamps of no. 44 type. Your radio may only have one dial lamp and it depends on what kind you install there. No. 1847 lamps draw only 150milliamps of current.
The rectifier is a no. 84/6Z4 type which has a separate filament winding requirement of 500milliamps at 6.3VAC. It would not be easy to find a readily available new manufactured transformer that would fill all of the requirements of voltages and current and still fit the chassis footprint of the radio. A replacement transformer would have to have two 6.3VAC filament windings, one capable of up to say 2.5 amps and one capable of the 1/2 amps the rectifier needs. The secondary windings of the transformer would likely have to provide about 390VAC across the end points and about 195VAC measured from the center tap to either end lead of that high voltage winding.
You may not find it easy to locate a type 84 rectifier. It has lower ratings for voltage and current capacity than the type 80 that is seen in many other Philco radios.
You might get lucky and find just a chassis available for spare parts with an intact power transformer. However, make sure it is checked before you spend your money. Also, make sure you have or can get a type 84/6Z4 rectifier tube before you go to far with any of this.
I did some checking against the schematic for your radio and I see these parameters about the power the transformer has to supply:
The B+ at the first electrolytic (item 61 ) is 270VDC and at the second electrolytic (item 58 ) is 185VDC. The field coil of the speaker serves as a choke and its resistance is 1100 ohms. There is an 85VDC drop across the field coil which means that the entire B+ load of the radio is drawing about 77.2 milliamps so round that up to 80 milliamps and that is the approximate power being delivered by the B+ circuits. The total amps of the filaments is about 2.35 amps if you allow for a couple of dial lamps of no. 44 type. Your radio may only have one dial lamp and it depends on what kind you install there. No. 1847 lamps draw only 150milliamps of current.
The rectifier is a no. 84/6Z4 type which has a separate filament winding requirement of 500milliamps at 6.3VAC. It would not be easy to find a readily available new manufactured transformer that would fill all of the requirements of voltages and current and still fit the chassis footprint of the radio. A replacement transformer would have to have two 6.3VAC filament windings, one capable of up to say 2.5 amps and one capable of the 1/2 amps the rectifier needs. The secondary windings of the transformer would likely have to provide about 390VAC across the end points and about 195VAC measured from the center tap to either end lead of that high voltage winding.
You may not find it easy to locate a type 84 rectifier. It has lower ratings for voltage and current capacity than the type 80 that is seen in many other Philco radios.
You might get lucky and find just a chassis available for spare parts with an intact power transformer. However, make sure it is checked before you spend your money. Also, make sure you have or can get a type 84/6Z4 rectifier tube before you go to far with any of this.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
