Bought this cathedral and I'm having trouble finding out any kind of print.
I suspect that it is a west coast manufacture by I think Gilifillan bros. under license from RCA. the tube line up is 280, 171A,226, 226, 227, 226.
There 4 resistors 2- all yellow that would make it 440k but they measure 1.8 & 2.4 k?? off quite a bit??
one is orange & black orange that would make it 30k and is 31k seems right
last one is solid blue that would be 66 m ?? I can't see that. Here are some pic's
That's a west coast radio for sure, but what an odd knob arrangement. It doesn't look like a hole has been filled where a third knob would be on the right, but I've never seen an odd knob set-up like this before. You'd think they would have placed the knob directly under the tuning knob.
I'd sure like to see a picture of the front of the chassis and the inside front of that cabinet if you get a chance. When I get back to my other PC I'll see if I can find a schematic in my Gernsback manuals; they seem to have a lot of the west coast sets that Riders doesn't.
Also, what does that little plate on the front of the cabinet say?
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
John
The small plate in the front says "Broadway" also never saw color coded tube sockets before and the speaker is nothing I have ever seen before. The coil was open and I rewound it about 2500 ohms of .0035 wire and I get static when I drag the leads across a 9v battery Bought it for $50 at a small store in Huntsville AL. The tubes all test good. If you have a schematic that would be great.
Eric
(This post was last modified: 08-31-2015, 12:37 PM by Eric.)
Eric, don't go by the color codes on the resistors. They were not standardized until years after that radio was made. Each manufacturer had their own coding for the resistor value.
I would assume that the resistors are ok for now until you can get some definite info on their proper values from a schematic or parts list. If you can let me know where each one is in the circuit, I can give you some idea of their nominal values.
I will leave the resistors alone.
The blue resistor goes to the grid pin 3 of the 27 tube it reads 2.5meg ohms
the first yellow goes to the vol control and the main transformer reads 2.4K
second yellow goes to the main transformer and ground reads 1.8k
orange resistor looks to go to the output xformer
the filter cap is listed as 16mfd it doesen't say there are 2 -16mfd but I have 2 red and one black leads. the Black goes to ground the two red ones goes to the Inductor? Should I take it there are 2-16 mfd's?
The resistor readings you mentioned seem reasonable for their application. The blue resistor connected to the 227 grid is the detector grid leak and 2.5 meg would be a typical value.
The yellow resistors are bias resistors connected in the filament circuits and a value around 2K seems reasonable. The fact that both are relatively close in measured resistance (+ or - 20%) is encouraging, rather than being wildly different.
I dont know the exact function of the 30K resistor, but it is probably a voltage dropping resistor for one of the stages and as such would not be critical.
Given that the measured values correspond to their circuit application, the radio will probably work fine with the resistors as is. If you ever find the schematic you can take it from there and confirm whether they are exactly correct.
As far as the 16 uF cap, I would guess that it is the total capacitance of both sections (8 + 8 uF). Otherwise it would have to be 32 uF total capacitance and such a paper cap would be physically huge, much larger than what you show in the photo.
Eric, unfortunately I looked through all of my Floyd Paul west coast documentation and Gernsback manuals and didn't find your set. I did find this ad for a Falck (made by Advance) that has a similar offset knob arrangement as yours:
You have a pretty cool early west coast set on your hands and I doubt that very many like yours were made. Unfortunately Los Angeles was the first to start pumping out midget/mantel sets and the technology was rapidly advancing so a lot of these early sets are not documented. I have three west coast sets that are not documented anywhere either: a Gilfillan, a Falck (Advance), and a Crown.
Even some of my documented sets like my Jackson Bell Peter Pan used two or three different chassis's during early and late runs. You might want to start looking through Rider manuals or go to Nostalgia Air and look for similarities to any Jackson Bell, Advance, Keller-Fuller, etc.:
New problem.. Looks like I have an open pri output transformer. I 'm going to see if it is in the leads and repairable.
that's not going to work lot's of green corrosion every time I lift a lead it breaks so... can i replace it with a standard output xformer or should I have it rewound and where could I get it done.
Eric
(This post was last modified: 09-01-2015, 12:08 PM by Eric.)
I don't think a regular output transformer will work in that radio. It has a high impedance magnetic vane speaker. What was the resistance of the speaker coil you rewound?
Replacement audio output transformers typically match impedance of the plate circuit of several thousand ohms to the few ohms of the dynamic speaker voice coil. Unless you rewind the speaker coil with only a few turns of heavy wire, the speaker will not present the optimum load to the plate circuit and you will get very low volume.
You might be better off using a high inductance choke to feed DC to the output plate and capacitively couple the speaker to it. This was standard practice with the radios of the period, such as the AK 40, Radiola 60 etc.
John
I have a P-T291 from Antique Electronic supply it's an 8 watt unit would it work? I looked at the 71A data but not sure what you look at is it load resistance? Primary impedance is 4000-10,000 ohms If not I will get the one from radio Daze.
Also posted info and pictures on Facebook in the Antique radio group since some have indicated being on the west coast maybe I can get some more info
(09-01-2015, 07:34 PM)Eric Wrote: John
I have a P-T291 from Antique Electronic supply it's an 8 watt unit would it work? I looked at the 71A data but not sure what you look at is it load resistance? Primary impedance is 4000-10,000 ohms If not I will get the one from radio Daze.......
It wouldn't hurt to try it, but I didn't really pay attention to that spkr before, so it may be a wildcard like Mondial suggests.
Good idea posting on the Facebook page, the more info you gain the better.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
