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38-38 conversion to AC? - Printable Version

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38-38 conversion to AC? - Greg Rodocker - 08-10-2014

I recently acquired a Philco 38-38 at an auction. It is almost in perfect shape. Is it possible to convert this to run on AC? If so where can this be done?
Thanks in advanced
Greg

RE: 38-38 conversion to AC? - vinzer - 10-05-2017

I just got a 38 38t I think I Will convert mine to ac using the circuit for a 38 23t.

vinzer

RE: 38-38 conversion to AC? - Radioroslyn - 10-05-2017

Geez I thought I had a lot of time on my hands.
Think it would be simpler to build a p/s to emulate the batteries. Well at least for the hv and filament supply the bias batteries would last a very long time.
Or you may want to consider building a battery pack that would power it. In this you can eliminate all of the interference from the ac mains. I have 39-80 (battery farm set) it plays quite well from batteries. Like supersized transistor radio.
The 1938 model use the older 2v tubes so a resistor in series is in order to drop 3v worth of battery power down to two. The '39 models use 1.5v tubes so D cell work fine.

RE: 38-38 conversion to AC? - vinzer - 10-05-2017

I built one for another battery radio but it  had room for batteries so I put it inside the radio but cannot do that on this one has no room for it . does  look to hard to change to ac.

Vinzer

RE: 38-38 conversion to AC? - dmaugus - 10-06-2017

I did that exact same thing a couple of years ago. Find a suitable power transformer and use schematic for model 38-9.

RE: 38-38 conversion to AC? - vinzer - 10-07-2017

I think I will use a 38 23 schematic no power transformer needed

Vinzer

RE: 38-38 conversion to AC? - vinzer - 10-12-2017

I did it now what do I call its not a 38-38 any more no quite a 38-23?

RE: 38-38 conversion to AC? - morzh - 10-12-2017

38-38 Renegade?

RE: 38-38 conversion to AC? - vinzer - 10-13-2017

Sounds good to me.

RE: 38-38 conversion to AC? - vinzer - 12-05-2017

Well I got to feeling bad about making a Franken Philco still had original parts changed it back to original and made a power supply.

RE: 38-38 conversion to AC? - Arran - 12-06-2017

That was probably the smart move, in my opinion, I've seen a few attempts where someone tried to convert a battery operated tube set into an AC set, with AC tubes, and they never seemed to produce a functional set afterward, they seem to get just so far, and then loose the handle. On the other hand I have seen a number of sets where someone retained the original battery tubes, and circuits, and constructed either an outboard power supply/battery eliminator to operate it from the AC power line, or built an inboard power supply in an empty area of the chassis, and almost all of those were successful. The nice thing about battery sets is that whilst the voltages and currents required are different from lets say a transistor radio, you can throw together a very good power supply using inexpensive off the shelf or salvaged parts.
Regards
Arran