The PHILCO Phorum

[attachment=24129][attachment=24128]                                                                                                  Hello everyone. I am an "older newbie" to tube radios. Always wanted to get into them, but just got active. I am a complete novice, with no background in electronics whatsoever (and little in carpentry). (I've been in the financial industry my entire life.) I picked up a few console radios in the last 10 days locally (within 50 miles) for what I thought were low prices- a Zenith 6S52 ($50), a RCA 811K  ($50) and a Philco 38-116 ($150). I have been gathering equipment (variac, isolation transformer, multimeters, soldering iron etc) and pouring over the Phorum, AntiqueRadios.com, and the internet (sites like Phil's Old Radios, etc). I have the Nostalgia Air schematics and have also downloaded the appropriate Riders manuals. I intend to join my state's antique radio club, NJARC.

I recognize this will be a looong process before I get to the RCA or even more so, the Philco. I intend to do a few tabletop radios and the little 6 tube Zenith console first. However, tabletop radios seem to be more expensive, even for basket cases, so I'm still looking for some candidates to fix/restore. This brings me to the Zenith: it's missing all four knobs, otherwise seems "complete" except one side of the cabinet has seen better days. Has all tubes and underside of chassis looks completely original. 

Right now I am looking for the appropriate knobs and searching out some veneer. After I decipher the components needed to recap it, I'll order those and really  begin the process- slowly. I will need lots of advice and help along the way I am certain.

Oh yeah, new chassis supports and replacement grillcloth needed as well. I understand the original type is unavailable as a repro- any ideas out there for this particular model?

Yes,

Renovated Radios is your go to place.

Welcome to the Phorum Steve 

I'll briefly touch on one of your radios, the 1936 Zenith 6S52.  A six tube radio it was the first in Zenith's lines of "Big Black Dial" radios that are very popular with collectors.  Although it's not apparent now, with the dial lights on the dial is actually fairly colorful due to bands of color on the rear of the dial face.  It also has a fairly deep chassis that should be easy to work on with lots of room.  Unfortunately, the correct original wood knobs might cost more than the $50 you paid for the radio, but that's just a fact of life with the Z knobs.  This site has a close-up of the correct knobs:

https://www.radiomuseum.org/r/zenith_6s5...h5619.html

It looks like you'll need two round, one pinched, and one pointer knob.  There are very nice reproductions available from:

http://renovatedradios.com/productlist.p...ondary=120

For reference it looks like you'd need a K16, K18, K15 and K14 for tuning.  I suggest just putting a set of cheap generic knobs on it until you are successful restoring it, and then do more research for the exact knobs used... those are just my best guesses since the only '36 I have is a 12 tube that uses a dual tuning knob.

Also, please don't power up these radios until you at least replace the electrolytic capacitors and out of tolerance resistors.  Below are two very clear schematics:

https://www.tubesandmore.com/sites/defau..._pg7-1.png

https://www.tubesandmore.com/sites/defau..._pg7-2.png

There is a long metal resistor mounted to the chassis shown near the top of the schematic.  These multi-section units are called a candohm and you should replace all sections if any of them are out of tolerance since they have a tendency to short to the chassis (I personally replace them all just to be safe).  The 11M is actually 11K ohms, Zenith used a M to indicate K ohms back then.  Good Luck and have fun!

I don't see why you couldn't work on the brand Z first, followed by the RCA, the 6S52 is basically the same chassis as one would find in a table/mantle model since it's a six tube chassis. It looks like the cabinet used to have a dark strip down the middle of the pilasters, and on the beaded molding just bellow the speaker grille, you can easily spot a refinished set online if everything was refinished on a monochrome. A guy that claims to have a refinishing business did this with an RCA-Victor model 281, posting pictures on the ARF, the legs were darker then the body of the cabinet, and had a black stripe on each leg, he redid them all in a medium brown, along with the rest of the cabinet. Your best bet for getting knobs would be to attend some swap meets, the Renovated Radios ones are plastic made to look like wood, alternatively you could play the fleabay lottery for originals, buy some wood reproductions (though I'm not sure about whether they make 1936 Z knobs) or contact someone like Mike Koste, or one of the other second hand knob vendors . With regard to table radios, you will find a few in short order, in fact one of our members would probably be able to supply you with as many as you require, he's out on Long Island.
Regards
Arran

Very nice finds, Steve. The Zenith 6S52 is a surprisingly strong player for a 6 tube radio. I've restored 2 of them in recent years. One thing you might find is an open field coil on the speaker. Seems to be fairly common on this model. There is a fix for it, though, and Mark Oppat can walk you through it. https://www.oldradioparts.net/index.html

You will also need a new dial belt. Those can be found here: https://www.qualityradiobelts.com/index.html

Good luck!

[attachment=24150]

Welcome to the Phorum ! That Zenith looks like it will be a nice set if it is not missing some critical parts. I don't see any shafts coming through the two lower holes on the right and left. Some controls might be missing, not just the knobs. One of the shafts I don't see is the band switch, a pretty critical part made from unobtainium these days. I hope this is just an optical illusion because the chassis is not pushed up properly in the cabinet. As for the knobs, if you aren't a fanatic purist, you can get good looking reproductions made of plastic that look just like the wood ones from a little distance here...  http://renovatedradios.com/index.php   I hope all the critical parts are there. It is a great radio and deserves to be restored. Good luck to you.

[attachment=24192][attachment=24194][attachment=24195][attachment=24191]

Thank you all!  

Morzh and Elliott Ness- Yes the wooden knobs are pricey (!)- I recognized that going in but for $50 for the console without knobs I went ahead. I think I will take the suggestion of using generic knobs for now- the cabinet needs refinishing (particularly the veneer on one side). Then I will reconsider...I also had read here and on antiqueradios that the Candohm is frequently a problem- we'll see.
 
Arran- the console seems to be original as you suggested, clearly up close shows several tones to the wood. Because of the veneer damage on one side and loss of lacquer on the right front I will probably end up stripping part or all .
 
NostalgiaRadioTime- that's a very nice Zenith. I hope mine will look something like that when I am done. I will need a new dial belt although you can't see that from my pics. I wish the Waves grillcloth was not ripped, I would love to find something as close to that as I can.
 
Mike-it has all shafts. I think it is pretty complete altogether except for the knobs (even has dial lamp shades, although I will replace them). It does however have severely compressed chassis supports so the knobs (until I get new supports) do not quite clear the openings. I have propped it up to show the shafts in a new attachment
 
I am posting several additional snaps of the top and inside of chassis. If anyone sees anything missing, please let me know. Can anyone comment about the Zenith antenna metal attachment to the rear of the cabinet?

Steve, thanks for the additional pictures. That Zenith is a great radio, and is going to be a wonderful player when you are done. Take your time with the restoration, and do it right. The folks here will be happy to help you out. Renovated Radios has all the rubber parts you will need, as well as the knobs. Here is the link to their page with the Zenith rubber parts http://renovatedradios.com/productlist.p...ondary=120  , and here is the link to their page with the Zenith knobs. http://renovatedradios.com/productlist.p...ondary=120  Believe me, these reproduction knobs look great, and are much cheaper than original wooden ones would be, plus they are available all at once. Take your time with the restoration. Yes, some of the parts to do it right are going to seem a little pricey, but that is what you have to pay for items that sell in small quantities to a niche audience. It is something that all of us in the hobby have to deal with. The trick is to take your time, and buy things along and along, fixing the radio as you get them. It does require patience, but this just adds to the feeling of satisfaction when you finally see the radio finished and performing as it did when it was new. I look forward to seeing your posts as you go along with your work.

Speaking of future posts, take LOTS of pictures as you work. Take several of the underside of the chassis from as close as you can focus the camera BEFORE you begin any work. Then take a picture at each stage as you go along with replacing the paper condensers, the electrolytic condensers, and any out of tolerance resistors. Don't let the term candohm throw you. It is just a long, tapped resistor mounted to the side of the chassis to dissipate heat. You can replace it with a terminal strip with suitable resistors soldered to it, or, if just one section of the candohm is bad, solder a replacement for that section between the terminals of the bad section, same resistance, and sufficient wattage to take the current which it will have to pass. All these pictures you take before and during the process will allow you to refer back in case you mess something up and need to see how things were earlier. They will also be fun for us all to see to follow your progress.

You might want to browse through some of the restoration threads on here from Ron, rfeenstra, and the rest, even me. You can see how we did things, and how to avoid mistakes we made, especially ME, LOL. Look at the cabinet restoration threads too. You can learn a LOT; things like what products to use, and what NOT to use, as well as how to use them. I know this is long, but I want to help you if I can so you will have a great radio when you are done; and, more importantly, the fun along the way, and the satisfaction of a job well done.

The 6-S-52 is one of my favorite Zeniths. Mine was in bad shape too. I had kept it in the "wood shed" before deciding to fix it up. Now I am glad that I did.

[attachment=24196]

I like the looks of that console, Russ and Greg! Looking at the photo of the chassis, it would seem there is a LOT of empty real-estate under there. It should be a breeze to work on.

Yep. Still have to change out that one cap -

[attachment=24199]

Forgot to include a pic of the underside-yes, lots of room under there! Considering how crowded some radio chassis are that I've looked at on line, this seems wide open.  Since I'm new to this, to those who have worked on 6-S-52's does anything seem missing?                        


 [attachment=24197]

And here's my initial take on the capacitors I will need to order to recap it (I included the original specs versus the appropriate ones to order for comparison.) I did not include any micas. This is the first schematic I have ever reviewed (attached-courtesy of Nostalgia Air). If anyone is willing to look, did I get any wrong? Also, what resistors if any should be replaced as a matter of course early on? Thank you in advance!

C2     .05 MMFD   200 V              3 needed                              .047 mfd 630v axial
C6    .001 MMFD  600 V              2                                          .001 mfd 630v axial
C7    .02 MMFD   400 V               1                                         .0022 mfd 630v axial
C8   .02 MMFD   600 V                1                                         .0022 mfd 630v axial
C9   .1   MMFD   400 V                2                                         .1 mfd 630v axial
C11   .1 MMFD  200 V                 1                                         .1 mfd 630v axial
C14   .1 MMFD  600 V                 1                                         .1 mfd 630v axial
C15   .0036 MMFD  600 V           1                                          .033 mfd 630v axial
Electrolytic:
C16   8 uF   450 V                     1                                           10 mfd 450v axial
C17   8  uF   450 V                    1                                           10 mfd 450v axial
C18   10 uF  25V                       1                                           10 mfd 50v axial

You have a few values on the order list that should be looked at. The. 0022mfd should be .022mfd and the .033mfd should be .0033mfd. Watch your quantities. If you need 5 or 6 of one value you might be able to buy 10 for the same price.

Measure the resistors and replace the ones that are over 20 percent off. I use 10 percent in my radios. Verify against the schematic as you go through them.

Yes, indeed, while you are ordering parts, measure all the resistors including the candohm. If any are more than 20% out from the stated value, or if the resistor is marked with silver, 10%, or gold, 5%, and beyond that tolerance, replace them. I never order smaller than 1 watt resistors these days, and I buy 1% metal film types. They are much smaller than the old carbon composite type they replace, and are smaller for higher wattage, so can handle over current better should that occur. I often use modern 3 watt metal film type to replace the old 1/2 watt because they are about the same size ! If the candohm is bad, or any section of it, feel free to ask folks on here about what wattage resistors to use in replacing it, or a section of it.