01-15-2017, 07:17 PM
Here's a old ad from Eaton Canada for the model 222 interesting.
Cheers
Lar
Philco Model 222
01-15-2017, 07:17 PM
Here's a old ad from Eaton Canada for the model 222 interesting. Cheers Lar
01-15-2017, 07:36 PM
here`s info on perma power
[Image: http://farm2.static.flickr.com/1503/2524...7e166c.jpg] [Image: http://farm2.static.flickr.com/1487/2577...550f84.jpg] Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift mafiamen2
01-16-2017, 03:31 AM
(01-15-2017, 01:27 PM)diamondsouled Wrote: Picked up a Rogers Magestic a while back that had a Perma Power Model A converter with it. Would that work with the Philco 222 as well? It should work, however I would want to rebuild the power supply electrically first, and then find out which settings to use for the number of tubes your set has. One thing to watch for is that Selenium rectifiers fail with age, that is the output current tends to drop, necessitating replacement. However it's not as simple as dropping modern silicon diodes/bridge rectifiers in as the internal resistance of a Selenium rectifier was higher then a silicon diode is, so that the output voltage using silicon rectifiers will be higher and will have to be compensated for on the "A"+ side. This can be handled in a number of ways such as with a wire wound resistor, but you can also use a number of silicon diodes connected in series across the load to bring the voltage down, about .7 vdc per diode. The filter capacitors inside the power supply will also need replacement. If you need a schematic for this set I have a set of Radio College Manuals and some Philco of Canada folders, but I can't guarantee that I have one for this set in the latter. You may not need one anyhow, more often then not these farm battery sets didn't encounter much servicing, in part because they were run for a low number of hours compared to an AC radio, and also because they ran cool and at lower operating voltages, and most were retired after AC power was introduced in a given area. This means that it's likely all original under the chassis, and all that you will need to do is carefully replace on component at a time, likely capacitors and possibly a few drifted resistors. If you want to test it you can connect ten 9 volts in series for the 90 volts B+ , and two or three "D" cells in parallel to supply the proper voltages, but don't mix the two up or you will be looking for a new set of tubes. You may find that this radio will still work after you connect the proper voltages to it, though I would still overhaul it if you intend to play it a lot. It looks like it was probably a decent performer though, in that it has a three gang tuning capacitor, that usually indicates that it has a tuned RF amplifier stage. Regards Arran
01-16-2017, 01:34 PM
01-16-2017, 01:38 PM
Arran,
I'm guessing that you wouldn't be able to use a variac in this case. I'm thinking through the Perma Power converter of course, after it's been gone through. Will be interesting to open things up and see what the condition is of some of those 60+ year old components. Thanks! Lar
01-23-2017, 01:54 AM
Lar;
You could use the variac to slowly power up the Perma Power power supply to test it, but it really isn't of any use in testing battery radios unless you have the battery radio plugged into the Perm Power unit whilst you do. If it has metal can filter capaciitors can you may be able to reform or recondition them by power it up on a variac, it won't help the selenium rectifiers if they have started to wear out though, if they are still good then you might be able to use the Perma Power using it over the short term. Slow power ups are really only useful for reconditioning old electrolytic capacitors and for catching electrical faults in a device before they can cause any real damage, battery radios have maybe one electrolytic capacitor whilst the rest are paper and mica caps. One thing that often causes trouble in battery radios is that the wires will break down inside the battery leads right near the plugs on the ends, so you may have to cut the plugs off and strip the wires back, this you can check with an Ohm meter first. Regards Arran
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