04-27-2026, 08:09 PM
Hey all, I had a chance today to pull down the 2 farm units from my upper cabinet display today. Some good news, and some questions for the group. Here are the models I have and some details. Pics attached also for reference.
1. Philco model 38 - built 1934:
According to my Rider volume IV (the schematic on the Philco site was pretty hard to read, but I have all the Rider volumes which comes in handy now and then) - this unit needs;
a. A supply: 2V, type 172-R - I believe this type refers to the Philco 2 volt lead-acid battery from the 1930s
b. B supply: 90V, type P-962 - another Philco type reference for heavy-duty battery back
c. C supply: -4.5V? or -9V? is that correct?
options:
- doesn't look like Rod's schematic design will work for this model
- doesn't seem like the Powr Shiftr will work either since it is 1.2v filament and no C supply - is that correct?
- ARBE-III will work - is that correct?
- one challenge will be hooking up the ARBE-III to the Philco 6-pin battery plug - is there a female plug end available somewhere that I could wire up to the ARBE-III, does anyone have a source for that?
2. Zenith model 6-J-230, chassis 5646, built 1938:
Here I lucked out - this unit is a 110V AC -or- 6 VDC unit. When I was originally looking at it, I only saw the 6V battery connectors and I didn't see the AC cord stuffed in the unit. It has a switch on the back to toggle between 110V and 6V. So, I can work on this one in 110VAC mode. I do have a separate power supply that can delivery the 6VDC if I wanted to test this out once repaired. So I'm in the clear on this unit. Well, in the clear for how to power it, but dang this unit needs some TLC haha. Gonna need to psyche myself up for this renovation.
Pics attached for reference. I really, really appreciate the time and effort everyone here has put in to throw out input and feedback. Super helpful.
Oh, wait a second, I know the solution to both of these units - BONFIRE!
1. Philco model 38 - built 1934:
According to my Rider volume IV (the schematic on the Philco site was pretty hard to read, but I have all the Rider volumes which comes in handy now and then) - this unit needs;
a. A supply: 2V, type 172-R - I believe this type refers to the Philco 2 volt lead-acid battery from the 1930s
b. B supply: 90V, type P-962 - another Philco type reference for heavy-duty battery back
c. C supply: -4.5V? or -9V? is that correct?
options:
- doesn't look like Rod's schematic design will work for this model
- doesn't seem like the Powr Shiftr will work either since it is 1.2v filament and no C supply - is that correct?
- ARBE-III will work - is that correct?
- one challenge will be hooking up the ARBE-III to the Philco 6-pin battery plug - is there a female plug end available somewhere that I could wire up to the ARBE-III, does anyone have a source for that?
2. Zenith model 6-J-230, chassis 5646, built 1938:
Here I lucked out - this unit is a 110V AC -or- 6 VDC unit. When I was originally looking at it, I only saw the 6V battery connectors and I didn't see the AC cord stuffed in the unit. It has a switch on the back to toggle between 110V and 6V. So, I can work on this one in 110VAC mode. I do have a separate power supply that can delivery the 6VDC if I wanted to test this out once repaired. So I'm in the clear on this unit. Well, in the clear for how to power it, but dang this unit needs some TLC haha. Gonna need to psyche myself up for this renovation.
Pics attached for reference. I really, really appreciate the time and effort everyone here has put in to throw out input and feedback. Super helpful.
Oh, wait a second, I know the solution to both of these units - BONFIRE!
Craftsmanship is an ongoing cycle of learning fueled by patience, persistence, and care, where every project refines our judgment and challenges our skills, in the steady pursuit of the Path to Mastery.




