Cleaning out our circa 1860s estate home and under the staircase found this. RCA Radiola 44 Model-594 radio and speaker from 1929. Fully intact and inside the case was a full set, still in their boxes, of unused spare tubes.



And I was able to find the schematic for it!

Lots of surface rust inside, dust, dirt, and bug detritus but no rat chewing. This should keep me busy for quite a while.

Edit: And! I have located the RCA Service Notes with full disassembly, assembly, alignment, antenna construction, and servicing information!

 

What a fantastic find! that should keep you out of trouble for quite a while.

 

Cleaning out our circa 1860s estate home and under the staircase found this. RCA Radiola 44 Model-594 radio and speaker from 1929. Fully intact and inside the case was a full set, still in their boxes, of unused spare tubes.
View attachment 325152
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And I was able to find the schematic for it!
View attachment 325155
Lots of surface rust inside, dust, dirt, and bug detritus but no rat chewing. This should keep me busy for quite a while.

Edit: And! I have located the RCA Service Notes with full disassembly, assembly, alignment, antenna construction, and servicing information!

That's a stunner and its quite similar to something I picked up in an Arizona antique store a couple years ago. Mine also had all tubes and in the interior looked very clean, almost unused. I haven't even powered her up yet. This isn't my model but is pretty much identical.

https://www.radiomuseum.org/r/sears_roeb_silvertone_g.html#images

That site also has a lot of history and schematics, in fact this looks like your radio

https://www.radiomuseum.org/r/rca_44.html

Its incredible to think these radios have seen and survived the great depression, prohibition and world war 2.

 

At least the service manual has all the disassembly instructions. There are 2 chassis. Tuning chassis on the left and power chassis on the right. The rusty boxes on the right are filter and bypass condensers (not electrolytic capacitors), Filter Reactor (whatever the heck that is? Choke?), and main transformer. Once I can clean room for it on the bench, I will need to remove the 2 chassis to clean and see if the transformer is not shorted or open. If it is that may be the end of the project... Should be able to check the plug before removing anything for a quick go/no-go.

 

They certainly don't make 'em like that any more. You going to try and keep it perfectly period, eg with appropriately insulated wire where perished?

 

This isn't my model but is pretty much identical.

Exactly! TRF Neutrodyne but mine is 5 tube. 3 UX-240s in the tuning chassis and a UX-245 and UX-280 in the power chassis. Only 2 of the tuning sections have overall shields (one copper and other is aluminum) and the hold-down bracket for the two shields is missing. Also someone moved the 2 tube shields from the 1st and 2nd tuning sections over to the power chassis so someone has already been into it long ago. I've seen better examples but living right on the coastal marsh everything around here is exposed to saltwater vapors so it's got a good sprinkling of surface rust. That can be cleaned up with steel wool to be repainted if I go there. The wood is in very good condition other than dust and a few bits of long ago paint splatter. A little elbow grease cleaning it and a coat of wax will bring it right back to looking great.

 

Exactly! TRF Neutrodyne but mine is 5 tube. 3 UX-240s in the tuning chassis and a UX-245 and UX-280 in the power chassis. Only 2 of the tuning sections have overall shields (one copper and other is aluminum) and the hold-down bracket for the two shields is missing. Also someone moved the 2 tube shields from the 1st and 2nd tuning sections over to the power chassis so someone has already been into it long ago. I've seen better examples but living right on the coastal marsh everything around here is exposed to saltwater vapors so it's got a good sprinkling of surface rust. That can be cleaned up with steel wool to be repainted if I go there. The wood is in very good condition other than dust and a few bits of long ago paint splatter. A little elbow grease cleaning it and a coat of wax will bring it right back to looking great.

Where did you find the service manual?

 

perfectly period

I was worried about tubes but with the "new" spares I hope that is not a problem. Resistors and capacitors may need upgrading though. Antiqued new cloth covered power cords and wire are available for not too much. IF I can get it back up I don't intend a museum quality restore but will try keeping it as original as possible. The tuning mechanism is bound up so a bit of penetrating oil to soak and loosen is needed.

 

Where did you find the service manual?

RCA-Victor-Service-Notes-1929-1930.pdf (worldradiohistory.com)
Great source for old books and such.

Edit: There are other sources that SELL old radio schematics and manuals but WRH is free.

 

J.A.C.K.P.O.T - !!!

And, WRH strikes again.

ak

 

The Radiola 46 is the same radio but in a different "cabinet" that included the speaker unit. I'm not certain but I think the 44 also had a base stand as the cabinet has cords coming out of the bottom without any "notch" for the radio sitting on a table to come out of. These were intended as a piece of furniture much like console TVs were in the day. In 1929, the list price of the Radiola 44 was $75. Quite a bit of money back in the days when hard working men were paid 10 cents/hour so 4-5$ a week. I went ahead and grabbed my multimeter and tested the power cord. It's OPEN! So, I'll have to get into the chassis to test it to be sure...

 

It's OPEN!

Well, DUH, the power switch was open... Still, very low resistance so I've got to get the cover off of the main terminals rail to check the transformer input directly. Nope, goes directly to the transformer... Hmmm...

Specs call for 4Ω across primary of XFMR so need to pull power chassis and put it on the isolation XFMR, dim bulb tester, and Variac to ramp it up and check.

 

This has come up before, but do you use a 1:1 transformer to isolate the radio/yourself from the incoming AC supply? Some of these behemoths have a live chassis, no idea if your radio does.

 

Pulled the power chassis and blew the dirt and dust out of it and performed the continuity tests and all looks good. Someone has added a wirewound resistor in series with the correct reading original but doesn't seem to affect the continuity tests.

 

This has come up before, but do you use a 1:1 transformer to isolate the radio/yourself

Absolutely! Not only an isolation XFMR but a dim bulb tester to alert for shorts and a Variac to bring the voltage up slowly. Now that I've got the power unit out and initial testing from the service manual done showing that everything (including the XFMRs primary winding) looks good, the next step is to power it up. Probably tomorrow...

Power Cord and ON/OFF switch are bad and will have to replace.

 

Please keep us posted. I have my fingers crossed.

 

I see that an external speaker came with it. If I recall correctly some of those older speakers did not use a permanent magnet and instead had an electromagnet that obviously need its own powers, not sure if your speaker is one of these.

 

I thought all the tubes were 4 pin but it's just the rectifier and regulator tubes in the PSU. The tuner section is all UX-224 5 pin amplifiers. Apparently some one had already swapped around some tubes because the 2 tube shields had been moved from the tuner chassis to the power chassis because they had put the wrong tube shape 24s in the tuner section and the shields would not fit over the replaced tubes. Turns out what I though were new in the box tubes may have been the original tubes. Still need to refurbish my TV7/AU mil surpuls tube tester which has 4 & 5 pin sockets and the tube data sheets for these old tubes...

 

not sure if your speaker is one of these.

It is. I've unplugged it from the PSU but haven't gotten into it yet. Has torn fabric grill cloth on one side so I did poke my finger in and check that the cone is still intact but nothing else so far. It doesn't match the pictures in the service manual for the outside shape of the RCA 100B speaker but I'm pretty sure the interior will as it is a heavy bugger.

I did find that there is a lot of veneer on the sides of the cabinet and some coming unglued. No cracks though and none missing so, if I can resurrect the electronics, the veneer can be repaired as well.

 

I just took mine down from shelf and took a bunch of pictures, I discovered that it was battery powered - 45V - never even noticed that when I purchased it.