Posts: 237
Threads: 24
Joined: Dec 2007
City: Gladwin, MI
Hi Guys,
Just thought I would post to the new forum. I just received a Westinghouse WR-10A tombstone radio. I purchased it because I wanted the transformer to restore my GE S-22A. Anyway, it came with a phono pre-amp installed that looks like it might have been a factory supplied option. It has a pre-amp volume control added to the front panel and the original 27 second detector tube has been replaced by a 56 tube, I suspect to reduce the filament draw, since there is an additional tube in the pre-amp. Oh, and the knob on the added pre-amp pot is exactly the same style as the original knobs on the radio. So, has anyone ever heard of a factory supplied optional phono pre-amp for such sets as the RCA R7, GE S-22, or the Westinghouse WR-10?
Ed
Posts: 909
Threads: 117
Joined: Jun 2007
Hello etech! I ran across the same thing on a 36 GE M-50(?.. I think that was the mod#) tombstone for a customer a few yrs back,however, the knob for phono input control was mounted on the rear chassis panel next to old-style 2-pin phono input connection. Knobs matched perfectly as fnt controls knobs also. Looked like orig factory install, but wasnt included in my Riders schematic at all if I remember correctly. Thats been awhile ago, I just remember noticing it, very unusual on those model sets.
I recapped the radio,got it working fine, but never tried using the phono as I dont have one.
Seems there was a spot on the tuning dial condenser that had a simple contact switch (looked orig too), that when the tuning condenser up past 1700 kc engaged, applied the phono input (simple copper contact touch switch). I remember scratching my forehead after I noticed it, asking myself..whats this?!Then I remembered the phono input would be activated. I got hum from touching the + input phono terminal after restoration with switch contacts engaged, but never tried a phono. I figure the phono input would have worked if needed.? I also have a 1929 Fada mod KW console w/ (trf) chassis with the same type phono input jack, except no extra phono input vol control. If I remember, it was shown in the early Fada schematic, and that set even has the old early "flash-o-graph" neon gas type tuning indicator tube which predates Philcos shadowmeters.
Didnt mean to get off-topic here. Hopefully someone here can help us both on that mystery phono setup question!
Posts: 237
Threads: 24
Joined: Dec 2007
City: Gladwin, MI
Randal,
Thanks for the info. That sounds like the phono pre-amp my radio came with. In this Westinghouse WR-10A, I'm thinking that this phono pre-amp may have been marketed as a kit from Westinghouse/GE/RCA to be sold and installed by the technician at the local radio shop. In this one, I'm pretty sure it was a manufacturer design, but the installation leaves much to be desired, leading me to believe that it was installed locally. Too bad that hole was drilled in the front panel for the new gain control. As such, nobody wanted it, and I bought the radio for scrap. Too bad, because the radio actually plays well. It only needs re-capping. Now I am undecided as to whether to pull the transformer or the whole chassis and install it in my GE S-22A or to try and repair this front panel and save this radio. Decisions, decisions, lol!
Ed
Posts: 909
Threads: 117
Joined: Jun 2007
you bet etech!... those decisions are hard to decide on working radios! I definately agree on your idea of a "retrofit" aftermarket add-on from the orig mfgrs! Otherwise, it makes no sense that the parts of the same "vintage", especially the knobs! I guess the tech that installed yours decided to make his install "user friendly", and locate the control upfront instead of the rear panel?
Just a guess. It is a shame that orig cab design was altered. Just as you, I have a few nice old sets that I bought for parts only, and found them to be great performers, albeit with ugly add-ons added before. (hee hee)
I have a few that someone conveniently drilled a hole in a nice wood tombstone case, and bypassed the orig on/off sw with a toggle sw.
Back then, those techs never realized that those radios would ever be collectible these days.
Hey, if nothing else, recap it, and let it be your daily workbench listener? Another trans will come along in the future, then you will have saved both!!
Posts: 337
Threads: 15
Joined: Nov 2005
City: Ortonville, MI
Slow down, guys!! Look at the tube in yhis "Preamp". It should be a 2A7. This doo-whatsis is an OSCILLATOR, and not a preamp. RCA had this thing for the attachment of a phono player to any radio. Using it, you didn't need to go into the set's circuitry to connect their phono attachment. I have one of tose things NIB, and you can see the ads for them in the RCA red books.
Check me out on this.
NOW, here's a funny thing. On the RCA R-7 sets, there's already a terminal strip for a phono attachment. This takes you right into the set's audio input. If I'm right about the oscillator, I wonder why they'd have not used the terminal board for the phono?
I much confuse.
Posts: 237
Threads: 24
Joined: Dec 2007
City: Gladwin, MI
This device (preamp or whatever) has a 57 tube in it. The 57 has a tube shield that looks like a 'goat' shield on it. It is wired down to the audio input terminal strip on the radio. It has a RCA phono jack on it.
Here is a picture of it.
[Image: http://i135.photobucket.com/albums/q136/...Preamp.jpg]
Ed
Posts: 337
Threads: 15
Joined: Nov 2005
City: Ortonville, MI
OK, this isn't the gadget I had envisioned. The addition of a 57 will get you a horrendous amount of pre-amplification. Looks to me like it was rigged to be a preamp for a GE or some kind of VR pickup. The tube socket mount to the cabinet is purely home-tinker stuff. I'd take it out, if it were mine.
I have both the R-7 and the R-7A sets. I've restored the R-7, and just got a good cabinet for the R-7A. The principal difference between the two models is the use of 47 tubes in place of the 45's. In that time, the 47 was (allegedly) a sensation in radio technology.They have more distortion than the 45's, but better power sensitivity. There was no improvement in power output either.
So, now, I can sleep well. The mystery is solved! In this hobby, you can never be sure of what happened to a radio during the 75+ years it has lived.
Posts: 237
Threads: 24
Joined: Dec 2007
City: Gladwin, MI
Thanks for the info Doug. Unless it was some kind of factory option, I planned to remove it. To bad they installed that darned pot on the front panel. I think I can repair it though. This radio is the WR10A version with the 47 tubes in it. At least the 47's are reasonably priced.
BTW, I also have a GE S-22A which is nearing completion. I have refinished the cabinet and was waiting for a new power transformer. I finally got one and the radio is playing nicely now. It is the same chassis as the WR-10A, using the 47's.
Ed
Posts: 909
Threads: 117
Joined: Jun 2007
The price of #45 tubes are outrageous! In several cases, I have "subbed" #47s tubes in place of the 45s by making socket changes from 4-pin types to 5 pin types, and rewiring sockets accordingly. Both tubes are close electronically speaking if you check the tube manual. Ive never had a prob in this conversion to escape the extra-expense, and no noticable sound quality difference that I could hear.
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