New project - Crosley 5-50

[PaulOF]

Christmas break has arrived and its time to start a new project. Sometime in the 1970's I bought my dad a Crosley 5-50 thinking he would enjoy getting it working, but it was one of the projects that he never got around to. It's been floating around my house since he died, and I finally decided it was time to have a go at it. It is the oldest thing I've attempted so far, but my success with the Electrola has emboldened me.

The case was pretty dirty and badly scratched:




I suspect that the switch is not original. It is not really very carefully installed, and it does not appear on pictures of other 5-50's I've found.

I decided to see what kind of job I could do of keeping the old finish using Gojo followed by Howard's. I used the darkest Howard's I could find on the dark portions, and Howard's mahogany on the rest.




It's not perfect, you can still see some of the scratches, but its way better ... good enough to be tolerable, and it saves the character of the original finish. I think I will try to enhance the gilding in the gooves with Rub 'n Buff. Then polish up the brass, give it (the brass) a coat of laquer, and re-install it.

Inside, the chassis looks pretty good.



I love the looks of those hand-wired rf transformers.

The capacitors all hold charge. One of the audio interstage transformers has an open primary, and the tickler coil is also open. These two coils are in series between B+ and the plate of the detector. I suspect that perhaps the detector's filament failed and fell into the plate, burning out both coils.
The good news is that there is a replacement available for the interstage transformer that will just slide onto the core of the original Crosley transformer. Here is the disassembled burned out transformer:


and the new coil on the core ready to be re-assembled into the case:


Removing the tickler, it looks like this:


When I unwound it, the wire fell into three separate pieces. Here it is re-wound:


It came with 5 01A's all of which test OK. The schematic shows a
112 or 171 as the final audio amplifier, but I suspect that the 01A it came with will at least have enough oomph to drive a pair of 2000 ohm headphones. Then when I win the lottery I can buy a 112 or 171. If I am reading the schematic correctly, I can jumper it so that it derives bias from A- and only need to cobble together A and B supplies, which will be tomorrow's task.

[bandersen]

Very cool! I've never worked on anything that old and find it rather intimidating

Ugh - I just checked eBay prices for 71As. I'd keep looking though. I did managed to pick up a couple good used ST types for less than $10 each not too long ago.

[Reece]

When I saw the first pictures, I thought, I hope he's going to try to preserve that finish. Great job! It does preserve the original look and character of the set. These twenties circuits are pretty simple. I've used one of those new transformer cores before in a Radiola IIIA and it worked great. I'll bet with an '01A as the output tube you'll get some usable volume from a high impedance speaker (or a modern speaker using an output transformer.)

[batterymaker]

One of my professors in college had one of those along with a Sunglow Melody Chest. He wanted to see if I could get either one going. My knowledge was much too scant back then, but the Crosley had a better chance to be restored. The Melody Chest had a tuning cap made out of pot metal and became warped and gnarled beyond use.

[PaulOF]

So, I've finally had time to get back to the 5-50. I put together a battery box

made out of stuff from Radio Shack. Holds 10 9 Volts for B+ and 4 D cells for A.

Poking around in my Dad's stuff, I found what looked like a nice Crosley speaker, Dynacone model F.


The bad news is that this speaker had an electromagnetic field rather than a horseshoe magnet. The worse news is that someone ripped out the internal workings and replaces it with a little 3" perm-mag modern dynamic speaker. Even though it's wrong for this radio, I hope I can find proper insides at some point.

So I dug out an old unrestored Radiola 100 I had laying around and hooked the whole thing up. Added a 10' antenna and ground, plugged in the tubes, turned up the filament voltage and ... nothing. Checked the wiring, and realized I had left out the jumper between A- an C. With that installed, I turned it on again and found KYW without much trouble. Good start, but I'm so closed to KYW that I can almost receive it by sticking an antenna into a bar of soap. I was concerned that I heard no sign of oscillation in the detector even with the tickler fully engaged.

A little further investigation showed that I had wired the newly re-wound tickler in backwards. After fixing that, even with the tiny 10' antenna I had stations all across the dial. The volume is not great, but better than I expected using the '01A as the final audio amp.

At this point, I reinstalled everything in the cabinet, and here is how it looks now:

The brass came up nicely with a bit of magic wadding followed by a coat of laquer.




Here's the front,


Side and the unrestored Radiola 100,


And the inside,


Finally, a close-up of the label.


So, at this point I'm a happy camper. This is the oldest thing I've worked on (ca. 1926) and I was a bit nervous about attempting it, but while some of the components looked exotic, the circuit was straightforward and there was virtually no unobtanium. Pretty much anything it it could be replaced or rebuilt if necessary. One thing it is missing is the dial paper. I hope I can find a reproduction somewhere. I'd also like, at some point, to find a proper Crosley Musicone speaker for it. Meanwhile I'll look into rebuilding the Radiola speaker. Has anyone here had experience with those? The entire supporting structure for the cone has disintegrated. It appears to be some sort of soft leather (Kid?) Is there reproduction grill cloth available?

So now onward to the next project. I think maybe it's this guy's turn.

[bandersen]

It looks really sweet I'm glad you were able to get it working after a fashion.

That's a real shame about the Dynacone. As for the TCA 100 grille cloth: check this out: http://www.grillecloth.com/pages/RCA100.php

[PaulOF]

Thank you, Bob. And thank you especially for the link to the howto page at grillcloth.
Paul

[JoeNewberry]

That's just gorgeous. Gojo and Howards are a miracle cure I'm going to have to look into. A shame about the speaker, but I'm sure there's a proper replacement out there somewhere for it.

Thanks for all the upclose pictures, especially the shot of the patent sticker.
Specifying who the radio is meant for, that it's got all Crosley parts which we should assume have patents pending on them, and we can see that the radio was built before Armstrong lost his dispute with de Forest. I especially like the warranty text though. Guaranteed for 30 days, and then only if you sent in the warranty card in the first five days of ownership. You'd think for something like this they'd have stood behind their workmanship a little longer.

[polyphase]

A very engaging and informative thread. Im grateful you started it.

I have a Crosley RFL60 with a Musicone speaker, which also lacks a permanent magnet, using plate current to generate a magnetic field. It looks great, goes with the set, but is a poor performer. I use it for show, but for serious listening I use a Western Electric WE540, which sports a big fat horseshoe PM. The tubes I use are #30, a substitute for the ubiquitous 01A of the time but with MUCH less filament power (60ma @ 2V). So two D cells can power the fils in my 5 tube Crosley for almost 30 hours.

I attach some pics for those interested..