Philco 112 Lowboy restoration (caution, lots of images)
Posts: 31
Threads: 12
Joined: Mar 2008
Hello,
I'm restoring my first radio, a philco 112 lowboy.
The radio was found on craigslist for $50. To my untrained eye it looks mostly unmolested.
[Image: http://farm3.static.flickr.com/2283/2359...52.jpg?v=0]
I have done a bit of work on the cabinet and it now looks like this:
[Image: http://farm4.static.flickr.com/3284/2366...c5.jpg?v=0]
Click for larger image
Next up is a new coat of lacquer.
I am now trying to wrap my head around tube electronics The top of the chassis looks like this:
[Image: http://farm3.static.flickr.com/2274/2359...97.jpg?v=0]
Click for larger image
And the bottom like this:
[Image: http://farm4.static.flickr.com/3157/2359...0a.jpg?v=0]
Click for larger image
As far as I can tell everything is original. I have avoided the urge to plug it in and have now removed enough components from it that doing so wouldn't get me anywhere anyway.
I've ordered a bunch of capacitors and resistors from JustRadios which will hopefully show up soon so I can move on with the soldering.
This model has a large very annoying 'condenser block' thing which seems to contain all the larger capacitors.
[Image: http://farm4.static.flickr.com/3295/2365...90.jpg?v=0]
Click for larger image
I wasn't able to get the innards out using a heat gun, so I moved up to heating the sides with a propane blow torch. That worked quite well and now i have the case free:
[Image: http://farm4.static.flickr.com/3064/2365...36.jpg?v=0]
Click for larger image
The heat did beat up the paint a little, so I plan to respray it.
In case anyone has ever wondered, the innards look like this:
[Image: http://farm4.static.flickr.com/3184/2365...40.jpg?v=0]
Click for larger image
and one of the capacitors unrolled like this:
[Image: http://farm3.static.flickr.com/2375/2365...71.jpg?v=0]
Click for larger image
Am I correct in thinking that none of these capacitors are electrolytics? They all seem to be paper.
I am replacing them all with film capacitors.
There is one coil which looks different from the others:
[Image: http://farm4.static.flickr.com/3233/2366...51.jpg?v=0]
Click for larger image
That is the best picture I could get of it. I understand these can corrode? is that what the little dots are? I haven't tested any of them for openness yet.
Anyhow I hope all my rambling is interesting to someone out there...
Posts: 33
Threads: 8
Joined: Nov 2007
Great pictures!!! I can't answer your question about corrosion. And, it's funny, I ALWAYS have that urge to plug it in when I shouldn't. Good Luck and so far so good...cabinet looks great too. Thanks for sharing.
Posts: 13,776
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Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Hi
The blistering on that coil is probably from heat.
You are correct in that none of the capacitors in the large black filter can were originally electrolytic - they were wound paper and foil, as you have seen for yourself.
You are going to have a VERY nice radio when you get it finished. Congrats, and thank you for sharing the photos!
--
Ron Ramirez
Ferdinand IN
Posts: 270
Threads: 12
Joined: Nov 2005
City: Nashville, TN
Hi,
I was wondering if there would have been room inside the can, right inder all the tar to add the new caps?
On my Philco 20, I removed very little of the tar inside the square can, then added the new caps underneath the tar, but mounted to the bottom terminals. That saved me a lot of trouble/mess, rather then emptying the whole can out.
Just a thought.. great job though coming along well.
Gary.
Posts: 393
Threads: 40
Joined: Sep 2007
City: St Clair Shores, MI, USA
Nice set. Always amazes me at the physical size of Philco's transformers. Huge and rugged!
-Brian
If you collect or are interested in antique telephones, please visit Classic Rotary Phones
http://www.classicrotaryphones.com/forum/index.php
Posts: 31
Threads: 12
Joined: Mar 2008
Yes, the transformer is crazy. It is, by far, the heaviest thing in the whole radio.
Posts: 31
Threads: 12
Joined: Mar 2008
There wasn't enough room in the can for replacements without some major excavation. And since i had to heat the mess anyway to get any of it out, i just heated it the whole way and pulled the whole mess out at once.
It is pretty easy. Just heat the sides while pulling lightly on the wires. At a certain point it will let go and the whole inside will pull out in one big piece.
Posts: 31
Threads: 12
Joined: Mar 2008
Update:
I had a little extra free time after the end of a business trip, and was able to do some final cleaning of the cabinet and spray on a new coat of lacquer. It now looks like this:
[Image: http://farm3.static.flickr.com/2281/2397...8d.jpg?v=0]
Click for larger image
I haven't decided yet if i will do another. There are a couple of problems with this first coat, but they are minor.
I have never sprayed lacquer before. Sadly it was a little thick for my gun (just a cheap air powered thing from an auto parts store). I should have thinned it. Because of this there is a slight texture to the resulting surface. But if you aren't looking for it you don't notice it.
Second view:
[Image: http://farm3.static.flickr.com/2060/2397...bd.jpg?v=0]
Click for larger image
Also my parts came in from JustRadios. So i have started the recapping process.
Recapped condenser pack:
[Image: http://farm4.static.flickr.com/3229/2397...08.jpg?v=0]
Click for larger image
And a rebuilt bakelite AC input filter block:
[Image: http://farm3.static.flickr.com/2324/2397...43.jpg?v=0]
Click for larger image
I wasn't originally planning to rebuild the blocks. But in the end it isn't hard to do, and they provide a needed mounting mechanism. It only takes about 30 seconds with a heat gun and a little piece of wire to remove the potting, Then maneuver the replacements into place and solder. Takes less than 5 minutes per block.
If I get really ambitious (and lucky) I might be able to finish the recapping tonight. We'll see.
Posts: 217
Threads: 40
Joined: Dec 2009
i typed every way i could how do you get to pictures i have a highboy 111 same schematic as 112 the sert plays but going to rebuild pics would help
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Some older posts here in the Phorum now have broken image (picture) links. The reason is because when the Phorum was started, it ran an older version of software. The newer software now running the Phorum requires that pictures be inserted in posts in a different way than was used a year or more ago.
I don't have time to go through every post and correct the image links.
So I depend on you, the readers and Phorum members, to notify me when there is any sort of problem.
The correct thing to do when you find broken links, pictures not showing up, etc., is to contact me via email or PM and let me know about it so I can fix the problem.
Thank you.
--
Ron Ramirez
Ferdinand IN
Posts: 217
Threads: 40
Joined: Dec 2009
you guys are totally tube u luar these pics will help alot the ones on the big black box are great thanks again give you guys 5 stars denver
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Joined: Feb 2009
Looking awesome! Must be very gratifying to see this coming along so nicely. You do very nice work.
tractorforum.com *** I reserve the right to be wrong
Posts: 217
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Joined: Dec 2009
i was wondering i ordered new caps for model 111 same as 112 looking at pics of cap block mine are not any thing likes in pics they sent me 4.7uf @450 volts 2 1.0uf@630 volts 1 0.47uf 630volts 4 0.22uf 630 2 0.15uf 630 volts 1 0.047 630 volts 8 0.015uf 630 5 0.01uf 630 volts which ones goes in big block ![Icon_idea Icon_idea](https://philcoradio.com/phorum/images/smilies/icon_idea.gif) looked on some links uf never came up on cap comparasons thanks denver ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
So what ever happened with this 112 restoration? I just spent the weekend on a early 112 chassis with pretty much the same layout. Got the set with no tubes and a friend did a beautiful job on the cabinet so now it is my turn to get the chassis ready.
Finally found a Hickok 530-B Tube tester up on my shelf that helped validate some tubes for it, and it seemed like it powered up OK with good audio and IF, but it took a while for me to pay proper attention to the tube basing and lack of plate voltage at the RF Amp. Traced it to the coil in the plate circuit was open and was able to find the break near the first turn and solder in a 'patch.'
Voila, we have a radio, just a little intermittently low on sensitivity and gain intermittently, but able to get stations all over the western US when it is working right :-). Probably still a bad cap in a block somewhere, as I didn't touch any of those or the condenser block. This set has great B+ and no hum.
Posts: 31
Threads: 12
Joined: Mar 2008
Sorry for not posting this earlier!
The 112 is now completely restored and works quiet well.
After recapping I powered the radio up through a dim-bulb tester through 25, 40, 60, and 100 watt lightbulbs. Small amounts of audio came out with the 100W bulb and generally everything seemed like it was fine. Power up straight into the wall produced loud audio and tuning seemed to work fine.
Generally it worked pretty well. But there was clear audio distortion coming from somewhere. Lots of random poking around led me to look at the speaker drive signal on my scope. This showed pretty clearly that part of the waveform was very truncated. Somehow (I don't remember how...) I figured that one of the 45 audio tubes was bad. 45 tubes are annoyingly expensive because some audiophile people love them. So I ended up replacing both 45s with 1619s from here ( http://www.dialcover.com/tubes.html). That completely solved the distortion problem. This problem also led to the only instance of electrocution in the project: when I foolishly decided to adjust the scope with one hand and the radio volume control with the other....ouch.
This is him all powered up (with the original 45s, one of which is blue):
[Image: http://farm3.static.flickr.com/2172/2399...a7_z_d.jpg]
And all put back together:
[Image: http://farm4.static.flickr.com/3049/2402...9a_z_d.jpg]
It currently has knobs from my (also now in restoration) 36-650. I need to find a source for the right knobs.
I use the radio about weekly. At power up there is a slight hum at about 3 seconds, and then audio comes through at about 15 seconds. It takes about 5-7 minutes before everything is entirely warmed up and stops drifting. I think there is slightly more hum than is supposed to be there. Also the volume control is annoyingly scratchy at the lower part of the range. It is a weird (to me) metal wheel in a carbon(?) sleeve affair. I've tried to clean it, but am afraid of harming it further. So I scrub it up and down every once in a while and live with it.
here is a picture of the volume control:
[Image: http://farm3.static.flickr.com/2220/2367...fe_z_d.jpg]
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