[Nick3092]

Last weekend I came across a 37-116 Deluxe in beautiful condition, with the original finish. It was a little more than I wanted to spend on a single radio, but the seller did come down to what is probably my upper limit on a radio. Given the condition of the finish and this radio's performance, I couldn't pass it up.

   

The seller said that he used it from time to time, and powered it on for me. I noticed the pilot and flood lights were not functioning. But the radio played quite nicely with a slight hum, but not bad.

So I got it home, and pulled the chassis. All the light sockets were suffering from the usual Philco spring/rubber melting issue. So I went through and fixed them all with a nylon washer and heat shrink like I've done on all my other Philcos. One of the springs broke, so i got a similar sized one from Ace Hardware. Its a bit stiffer, but seems to work. I also see that the two 8uF filter caps were replaced at some point. All the other electrolytic cans appear to be original.

The dial is in good shape, but doesn't always move with the vernier dial and tuning cap, so I need to disassemble that mechanism and see what is going on there. All the station tabs are missing or broken. The tabs all look to be made of the same phenolic material the dials are, vs the cardstock/paper tabs used in the later '39/'40/'41 models. Can't say that I've seen anyone (meaning Mark O. or Radio Daze) reproducing these tabs. Is that the case? Has anyone tried substituting the cardstock tabs on this dial? If so, does it work OK?

I ran all the tubes through my Hickok 533A, and all but 3 tested strong. I tested the 3 that did were coming up as bad/questionable on my Weston 981-1, and they were above the reject point. Given the radio works and at least one tester shows them as good, I'll probably leave them as is.

Under the chassis, it appears only 2 wax/papers were replaced. I didn't look at the schematic to determine which two, but I will replace them all. And I noticed one side of the 4k/1k candohm opened up, as someone put in a ceramic tube resistor to replace half of it. And surprisingly, didn't use the open terminal on the candohm, like every other candohm repair I ran across.

I'm currently in the planning phases, and looking for some input. As with any Philco, I've already ordered the info pack from Chuck S. I've compiled a list of the caps and resistors using the copy from NA and will be ordering them in the near future. I'm not going to start any work until I have all the parts, so I'm not sitting around for a week or two at a time waiting for something.

For the filter caps, I'm assuming they were originally 8uF and most likely rated 475v. The current cans are 8uF and 600v. I see that in the run changes on NA, they dropped the filter caps from 8uF to 4uF in run 5. If I understand correctly, usually a lower capacity lowers the amount of filtering. But it also drops the rectifier voltage a little bit (I'm basing that assumption off the fact if you up the capacity, it causes the voltage to go up). I usually order exact values whenever possible from Dave at JR. He does have 8 and 4uF's @ 450v. But with 5v rectifiers, I've heard it's better to go with 500v caps instead. I haven't checked DK/Mouser, but the smallest 500v Dave has is 10uF. Given I'm assuming Philco saw a benefit to decreasing the filters from 8 to 4, should I do the same? And for the voltage, am I better off trying to track down a 500v regardless of what uF value I go with?

The other burning question right now is the candohms. I'm not a fan of them, and usually replace them even if they do appear to be functional. The problem here is they are mounted close to each other, and in a somewhat inconvenient place. And I don't know what wattage to replace them with. It looks like one of the candohms (part 118) is actually just a single section 14k .5 watt resistor. If it's only .5 watt, I'm sort of surprised they used a candohm, as you would think it's not putting out that much heat. As usual for candohms, there is no rating on the 4k/1k (part 124). Any suggestions on wattage ratings here for replacement resistors?

As for working on the chassis, there seem to be 2 schools of thoughts. Remove the wires connecting the RF section, and remove it completely. The other is to some how fold it all up like a rubiks cube and not detach the wires. Any pros/cons to either approach? I would like to replace the 3 rubber bushings on the RF sub chassis anyway, not sure if that makes either method more desirable.

And speaking of the rubber pieces, I'm looking at Renovated Radios to see what I need. On two of the shafts on the front, there are 1 each of the spacer grommets (GPH-spacer) and 2 each of the smaller spacers (GPH-spacer2). Is that correct? And securing the chassis was only a single screw with a metal sleeve. Is any kind of grommet supposed to be around that sleeve? On 2 of the corners, I have some badly deteriorated chassis washers. I can't measure them as they are flattened and distorted. Would CW8 be the appropriate washers for the 4 corners? And for the 3 grommets on the RF sub chassis, would i go with GPH-RF or GPH-690-RF?

I've restored around 11-12 radios in the past, a few Philcos, a few RCA's, and a couple other brands. The biggest ones I've done were a 40-180 and an RCA T10-1. The 40-180 is not as "big" of a radio, but the chassis was roomy and I had to replace all the rubber wiring. The RCA was bigger component wise, but still roomy. But this one dwarfs hem both in size and complexity. Given how nice this radio is, I want to take extra time and make sure I do it right. So I welcome any input or suggestions on how to handle this radio. I've never done a thread with continual updates while restoring either, so I think I will give that a try with this thread.

Thanks in advance for any feedback/tips/answers. I know I just dumped a lot into this first post, but once I started thinking about everything, my brain wouldn't stop.

-Nick

[morzh]

I have this, restored a year ago, plus sent one to a friend in Ukraine (he got it a week ago, came intact which in itself is a miracle).

1. Full recap.
2. unless you want a bit easier access to caps in RF chassis, no need to lift it, partly or in full. I only had a problem with one cap, but was able to deal with it.
3. Resistors. Change on the basis of check results, in my case most did not need to be replaced.

4. When taking apart dial assembly, photograph or sketch in detail every small step.
5. The dial hub might separate you could glue it back if the separation is not damaged apund. Otherwise repros are available. Mark Oppat is one.
6. Do not play it anymore before you replace electrolytics or make sure they have been replaced recently.
7. Check all tubes. Even if it plays.

[Steve Davis]

That is a nice looking radio.

Steve

[morzh]

37-116 has one of my most favorite colors.

[Nick3092]

1. Full recap.

Yup. That is always the plan when I get a new radio.

2. unless you want a bit easier access to caps in RF chassis, no need to lift it, partly or in full. I only had a problem with one cap, but was able to deal with it.

Hmm, I'll have to take a look. I need to devise some kind of stand or something to work on this thing.

3. Resistors. Change on the basis of check results, in my case most did not need to be replaced.

I usually shot gun the resistors while I'm in there. I don't want to have to re-work these radios in 10 or 20 years again. And odds are the existing resistors aren't going to last for ever, even if they are in spec today.

4. When taking apart dial assembly, photograph or sketch in detail every small step.

Noted. I always have my phone next to me while working on radios, and try to take lots of pictures, but sometimes I get so involved, I start forgetting.

5. The dial hub might separate you could glue it back if the separation is not damaged apund. Otherwise repros are available. Mark Oppat is one.

I'm hoping the dial is still good all the way around. Mark's repro's are great. but he hasn't been able to find a supplier for the phenolic material for a while, and he's running out of a lot of his dials. Radio Daze quality is below his, but they do have a line on some supplier. I wish Mark could find out who their supplier is so he can get his back in stock.

6. Do not play it anymore before you replace electrolytics or make sure they have been replaced recently.

The original 8uF filters were replaced with some other cans at some time in the life of the radio. Regardless, now that it's on my bench it won't see power again until I'm done working on it.

7. Check all tubes. Even if it plays.

As noted above, I ran them all through my 533A. It found 3 to be unknown or bad, but running them through my Weston 981-1 showed them above the reject point published by Weston. So they should be good. I tend to trust the Weston a little better than the Hickok, but the Hickok has far more tube data available, and is a little quicker to set up. So it's usually my primary tester.

That is a nice looking radio.Icon_thumbup

Steve

Thanks. I was shocked at how well the finish held up. The bottom "legs" are showing wear, but the rest looks great.

[morzh]

Even if tubes show in "replace"... in my case three tubes were plain dead, Both 6J5 (what a coincidence) and the rectifier was also full dead, no emission at all.

But both output 6A5 (there is a version with those instead of 6B4) were in "replace" and not fully dead.
I left them in, they play just great.

[462ron]

Hi Nick, nice looking set..in better shape than mine was when I got it. When yours was playing, did you happen to try band #2 and if so did it work? Seems like a lot of these 37-116 have a bad band 2 oscillator coil as mine did. Just to give you a heads up. Also, I bought a chassis stand to work on this chassis as it is very heavy and it worked great.

Ron

[Nick3092]

Well, I haven't done much with this so far, other than trying to figure out all the parts I'm going to need.  So far I ordered all my caps from Dave, bulked up my supply of resistors, and got some rubber parts from Ed.


Last night I decided to see why the flood lamps weren't working.  Looking at the schematic, i saw they were swiched with the magnetic tuning.  I naively thought that it must have had the mag tuning off when it was last powered up. All the tubes were pulled so I powered it up just to get power on the filament circuits.  The pilot bulb came to life, but turning the mag switch either way didn't work for the floods.

So I traced out the wires and found the wires coming off the front of it that ground out the mag tuning when off and the filament wires on the back.  I grabbed my DMM, and found that there was no continuity between the filament string one one lug on the back of the switch and the other lug that connects to one leg of the of the flood lamps.  So I desoldered the wires and pulled the switch out.

Here is one view of the switch that makes/breaks continuity to the flood lamps:
   

This picture is after I fixed it.  When you rotate the switch, a wafer style switch on the frond grounds out the mag system.  Then there is a plastic switch mounted to the back.  There is a "foot" on the end of the shaft that is supposed to flip the switch.  But instead I found a bent piece of metal that the foot was just riding up on top of.  The red line was how that side of the switch looked originally.  I stuck my needle nose pliers in and was able to straighten it.  It now properly flips the connection back and forth.  I shot some Deoxit D5 in for good measure, worked it back and forth.  Then I sprayed some F100 Faderlube around the foot and inside the plastic switch to hopefully decrease any resistance that made it bend in the first place.  Put it in, connected everything back up, and now I have working flood lamps!

Speaking of, does anyone know what bulb they should be?  The parts list just lists the floods as an assembly.  Who ever worked on it last put in an assortment, apparently of whatever they had on hand.  I know the pilot is 55, and it has a big round deflector.  This has a narrow deflector, So I suspect they used a "tube" style bulb, like maybe a 44 or a 47 instead of a globe like the 55.  I think the 38-116 used 44's.  But it also only used two of them instead of 4.

[thirtiesradio]

That's a beautiful radio. The condition of the cabinet is how you like to find them

[Mondial]

I would consider using 8.2 uF 630 V metallized polypropylene caps for the two filters right after the rectifier. These can handle much greater ripple current than modern electrolytics, and they will basically last forever. 

I have been using this type of cap for the first filter in several radios and they work great. They are about $6.50 each from AES and small enough to stuff inside the original electrolytic cans.

[Nick3092]

I would consider using 8.2 uF 630 V metallized polypropylene caps for the two filters right after the rectifier. These can handle much greater ripple current than modern electrolytics, and they will basically last forever. 

I have been using this type of cap for the first filter in several radios and they work great. They are about $6.50 each from AES and small enough to stuff inside the original electrolytic cans.

Hmm, I think I saw those once, and sort of balked at the price. Long lasting is a plus. I've never actually restuffed a can before, and given how big those are, I'd pretty much have to. There wouldn't be room under the chassis for that.

However, that takes me back to my 4uF/8uF question (where Philco dropped from 8uF to 4uF for the filter caps in run 5). I can't find a run number stamped on my chassis. But I can tell I at least have a run 6. In run 6 it says they moved the two 25k resistors from hanging directly off the interstage transformer to directly on the 6B4 sockets. Mine has this change made, so I think it's safe to assume mine is at least a run 6. However, along the way someone replaced the original filter cans, and threw in 2 non-Philco 8uF cans with wire leads. Not sure why they would have done that, assuming the originals were clearly marked 4uF. Unless they just looked at the schematic (and not the run changes), and figured someone else put in the wrong values, so they should put in the 8's.

What are the overall effects of changing the values of the filter cap values? All I know is that if you go higher, you might get better hum elimination, but you could raise B+ too much. And should I go with 8uF or 4uF?

Thanks!

[Mondial]

That's a good question as to why Philco changed from 8 uF to 4 uF filter caps. Perhaps it was because they were having reliability issues with the 8 uF? It is quite unusual to go to a lower value cap as the ripple will increase. If they wanted to reduce the B+ supply voltage, Philco most likely would have changed the power transformer secondary winding rather than reducing the filter capacitance. I do know that they went back to 8 uF in the next years model 38-116.

Another factor is that the actual capacitance of the early electrolytics was usually higher than the marked value, so the later 4 uF might have been closer to 8 than to 4 uF.

I would still recommend the 8 uF polypropylenes. They have a tight tolerance so their value will not exceed the marked value by more than 5%. If you use 4 uF 500V miniature electrolytics, they will not have a ripple current rating high enough to survive for long in this application. 

In general, increasing the value of the first filter cap right after the rectifier will increase the DC voltage and decrease the amount of ripple. How much depends on the DC current drawn from the supply, the higher the current, the greater the effect. Looking at the original 37-116 schematic with the 8 uF filters, the DC voltage readings seem to be right in line with what would be expected, so I don't see why they would want to reduce the B+ supply voltage by using lower capacitance input filters.

[PhilcoMike]

Wow, no need for grill cloth either!!!

Mike

[Radioroslyn]

I've got two 37-116's would like to know what you are going to use for the rubber parts for the subchaiss. Size  and p# would be very handy!!! I'm assuming that you are getting them from R/R
Tnx Much!!
Terry

[Nick3092]

I bit the bullet and ordered the 2 Solen 8uF caps from AES.  They had a couple other odds and ends I was thinking about getting anyway, so it gave me more incentive to order them as long as I'm already paying the shipping.  Now I'll have to go review the tutorials on restuffing cans.

I do have another question on the dial mechanism.  The vernier shafts always turn the tuning capacitor.  But the automatic dial hub (and the dial itself) sometimes spin, but mostly does not.  Does that mean I need to go through the procedure of increasing the vernier tension as outlined in the automatic tuning doc?  I'm assuming the whole assembly should be turning as one.  I really do not want to disassemble this mechanism further than I did to get the dial and mask out (before they get damaged).

Hi Nick, nice looking set..in better shape than mine was when I got it. When yours was playing, did you happen to try band #2 and if so did it work? Seems like a lot of these 37-116 have a bad band 2 oscillator coil as mine did. Just to give you a heads up. Also, I bought a chassis stand to work on this chassis as it is very heavy and it worked great.

Ron, sorry I missed your post before - just noticed it now.  I did not try the radio on anything other than BC while at the seller's house.  I'll be sure to ohm out the coil and make sure all is good.  I have rewound two outer coils on my Philco 60B.  They were well documented and easy to do.  I don't know that I could say the same of these coils.

Wow, no need for grill cloth either!!!

Yeah, its in amazing shape.  It is pulled away slightly from the right side of the cabinet in the lower right clarifier grill.  Its not too noticeable in the picture I posted earlier.  But it is in person.  Not only do you see the gap, the V pattern doesn't line up with the middle pillar.  I was going to post a pic and question in the cabinet subforum to see if that would be easy enough to fix.  If not, it can stay that way.

I've got two 37-116's would like to know what you are going to use for the rubber parts for the subchaiss. Size  and p# would be very handy!!! I'm assuming that you are getting them from R/R
Tnx Much!!

I emailed Ed at R/R and asked him for clarification on which of the two RF sub chassis kits I needed.  He said to get the GPH-690-RF grommets.  So I did.  I also got the GPH-RFTR to go on the back of the tuning cap, and CW8 for the corners of the chassis.

Speaking of the rubber parts, on 2 of my 4 shafts there were a real thick washer (that appear to be the same as Ed's GPH-spacer) and 2 thinner ones (that appear to be the same as GPH-spacer2).  Those 6 pieces all seemed to be in pretty good shape, so I didn't order new sets of those.