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-   -   Restoration of RCA Victor R-98 1939 table top victrola (http://www.videokarma.org/showthread.php?t=255686)

Bill Cahill 09-25-2012 12:28 PM

Restoration of RCA Victor R-98 1939 table top victrola
 
Hi.
I've had this machine for more than 30 years.. At one time I had it playing, but, sound was weak. Then, other problems happenned, and, it got set asside for the last 24 years. I'm now finally back on it.
Started out by polishing the chassis, and, speaker.
I have repairs to do, and, case work to do.
Pictures are mixed, up. Sorry. But, I'll be doing this possibly in sections.
Well, here goes. Here are photos of it. Oh. By the way.
Tube line up follows: 1 5U4 Rect. 2 2A3 Audio Output. 2 6J5. ONe is inverter, other is pre amp.
It uses a driver transformer for ouput stage.

http://i18.photobucket.com/albums/b1...abinet0005.jpg

http://i18.photobucket.com/albums/b1...abinet0003.jpg

http://i18.photobucket.com/albums/b1...abinet0007.jpg

http://i18.photobucket.com/albums/b1...abinet0006.jpg


http://i18.photobucket.com/albums/b1...abinet0004.jpg

http://i18.photobucket.com/albums/b1...abinet0001.jpg

http://i18.photobucket.com/albums/b1...abinet0002.jpg

http://i18.photobucket.com/albums/b1...abinet0005.jpg

http://i18.photobucket.com/albums/b1...abinet0007.jpg

http://i18.photobucket.com/albums/b1...orR-980025.jpg

http://i18.photobucket.com/albums/b1...orR-980021.jpg

http://i18.photobucket.com/albums/b1...orR-980023.jpg

http://i18.photobucket.com/albums/b1...orR-980024.jpg



Well, what do you guys think? It was sort of playing 24 years ago, but, after getting the correct schematic for it, I found out the electrolytics I had put in, all at 450 volts, were too low. I needed 500 volt instead..
I think several of the parts are chrome plated.
I believe apeaker frame is also chrome plated.
Magnet assembly isn't.
Bill Cahill

Bill Cahill 09-25-2012 12:38 PM

Here are more pictures of it.

http://i18.photobucket.com/albums/b1...orR-980025.jpg

http://i18.photobucket.com/albums/b1...orR-980021.jpg

http://i18.photobucket.com/albums/b1...orR-980023.jpg

http://i18.photobucket.com/albums/b1...orR-980024.jpg

http://i18.photobucket.com/albums/b1...orR-980015.jpg

http://i18.photobucket.com/albums/b1...orR-980017.jpg

http://i18.photobucket.com/albums/b1...orR-980018.jpg

http://i18.photobucket.com/albums/b1...orR-980016.jpg

http://i18.photobucket.com/albums/b1...orR-980011.jpg

http://i18.photobucket.com/albums/b1...orR-980013.jpg

http://i18.photobucket.com/albums/b1...orR-980007.jpg

http://i18.photobucket.com/albums/b1...orR-980009.jpg

http://i18.photobucket.com/albums/b1...orR-980003.jpg

http://i18.photobucket.com/albums/b1...orR-980001.jpg

http://i18.photobucket.com/albums/b1...orR-980024.jpg

Well, what do you guys think? It was sort of playing 24 years ago, but, after getting the correct schematic for it, I found out the electrolytics I had put in, all at 450 volts, were too low. I needed 500 volt instead..
I think several of the parts are chrome plated.
I believe apeaker frame is also chrome plated.
Magnet assembly isn't.
Bill Cahill

maxhifi 09-26-2012 10:50 AM

Wow did you say push pull 2A3s, in a table top phono? This thing is awesome, certainly one of the nicest of the sort I've ever seen. I can't believe that by 1939 it wasn't based on a 50L6 output stage or at best a 6V6. I hope you get it going. I'd be tempted to modify it to play LPs to get a bit more use out of that amazing amplifier and speaker!

Bill Cahill 09-26-2012 07:33 PM

I have plenty of 78's, so, no prolblem there.
I'll get it playing again. I had it playing to some degree then.

This was a fairly expensive machine. Yep. I did say two 2A3's in push pull.
According to RCA records it puts out 12-13.5 watts of audio power.
It's a good machine.............
Thanks.
Bill Cahill

holmesuser01 09-29-2012 10:06 AM

I'd happily take those old klunky 2A3's off your hands, Bill...

Seriously, that's a great amplifier.

I got one built around 1933 that was used for back-up in a movie theatre for about 60 years that used 4-2A3's. Two were missing, and I was amazed to find 2 in my tube stash. They all check very good.

I did a full re-cap on it, and I use it with an FM tuner today. It sounds really nice.

I look forward to the progress on this phono. I've got projects that have sat around just as long as this one has for you.

All the best!
Bruce

Bill Cahill 09-30-2012 08:15 PM

Tried amplifier yesterday. I ended up having to try a cheap crystal cartridge.
Not touched original player yet.
Amp has good, clean sound, but, lackng bass.
I suspect mica caps are shot.
I'll have to work on that.
When I rebuilt it I used mylar caps on output stage. It had paper caps. Yet, schematic called for mica caps there. Someone may have replaced those long ago.
One of the cans had been replaced with a cardboard 450 volt filter. That's long gone, now.................
Well, it works, but, needs more work. When that's done, I'll bring cabinet into the shop, and, replace bad pick-up wire.
Bill Cahill

Bill Cahill 10-01-2012 05:02 PM

Hope to get back on it tommorrow. Vol. was o.k., but, not great. Found out coupling resistor for cartridge had doubled. I'll replace that.
I think what's left of mica caps have gone south.
I'll replace them.
The volume control in this actually has two tone taps. Not bad, says I.
Speaker is good, and, transformers are still good.
Wheww!!!!!
Bill Cahill

Electronic M 10-01-2012 05:27 PM

Homina, homina, homina....drool...(wipes mouth). That thing must be the E.H. Scott of 78rpm phonos.

I bet it will sound GREAT when you are finished working on it.

Bill Cahill 10-06-2012 08:50 AM

It's been a rough week here, so, in spite of getting some caps for it, I haven't been able to work on it, yet. Hope to soon.
I'll post when I do....
Thanks.
Bill Cahill

radiotvnut 10-06-2012 11:35 AM

That's a nice machine and I hope you get it going soon!

Reece 10-07-2012 11:22 AM

That's really hunky for a table top record player. Wonder if it was intended for something like school use, powerful output and manual player, no radio. The chassis is full of extra holes plugged up: wonder if the chassis was shared with a radio model or PA amp or some other product.

Bill Cahill 10-07-2012 04:10 PM

Looks like it might have been also used for one of their radios.
The plugs are nickel plated, also.
Bill Cahill

Bill Cahill 10-15-2012 11:45 PM

I posted this in both ARF, amd, my own forum tonight. Thought you'd be interested. Here goes................

I have had this machine for over 35 years. When I got it it was still barely playing with it's original 1939 factory Crystal cartridge.
I repaired it at the time, and, it put out some audio, but, not alot.
Well, alot happenned, and, I haven't touched it in 20 years, approx.

I got back on it about two weeks ago after my flyback fried in my Raytheon tv.
I put new electrolytics in it again, and, started repairs.

Well, it's still got issues, but, guess what!!
The original crystal cartridge is still very much alive!!!!!!
The wire leading to it was shorted because rubber insulation on center wire had crumbled off.
The wires solder to the back of the cartridge, and, there is a shorting switch mounted on the cartridge to short it out while changing needles.
I don't have great wire, and, it's causing me major headaches. But, with fiddling around, I get fairly decent volume out of that cartridge, with good bass response.
I can't play a record yet because of mechanical problems, including a gummed up motor.
But, with difficulty, I can drag a record, and, it had decent volume, admittedly with vol control turned all the way up, but, still, decent volume, with good bass.
I'm not even going to rebuild this one. I'm leaving this cartridge alon!!!!
:D :D
Bill Cahill

Bill Cahill 10-16-2012 01:28 AM

Did some messing around with motor, and, connections, and, a fussy mercury switch, and, got it to play records. With original old saphire needle it was distorted. I put a new 78 needle in, and, now, it plays GREAT!!!!!
Lots of volume, good bass, clean, and, clear.
I am IMPRESSED!!!!!
Bill Cahill :banana:

Reece 10-16-2012 02:58 PM

That's some find. Does it have any other function, like a mike input? Or just plays records?

EDIT: answered my own question; it plays records only. Here's the schematic. Quite a player.

http://www.nostalgiaair.org/PagesByM...5/M0015735.pdf


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