Into the fray with a 116X
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City: Lehighton
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I finally pulled the chassis from my 116X yesterday but first, I brought it up slowly on the variac. At 95 volts she came alive with a loud hum. But, she also was faintly pulling in a couple of stations. Wonderful! I shut it down, yanked the chassis, and started to replace the power filters. Surprise, surprise, someone was in there ahead of me, a very long time ago (Repair is dated 7-15-1940). Unfortunately they didn't do a very good job. The double lytic (8Mfd-500V, 100Mfd-100V) had been replaced with (8Mfd-475V, 8Mfd-475V). The real problem was they had pulled the grounding lug off of the old can and just slipped it up between the new can and the clamp. However, the new can was actually a cardboard replacement, not metal, and it shrank over time allowing the lug to slip out as soon as the wire was touched. Not sure what, if any, contact the lug had with metal.
I replaced all three power filters, reconnected the chassis, and brought it back up on the variac. Good news is she plays; bad news is the speaker's bad. At minimum/low volume it's fine but as soon as you start to bring the volume up it starts to seriously buzz and rattle. Since the horsehair around the top and bottom of the speaker has been eaten away (I guess the little devils couldn't reach the horsehair on the sides) I suspect the cone is damaged by the mice who lived in there for a long time. Hopefully the speaker in my parts radio is good.
The amazing thing is it has all Philco tubes in it and I think they're all original. That was a nice surprise. Also, the shadow meter appears to be in working order.
[Image: http://i863.photobucket.com/albums/ab191...16x-1s.jpg]
[Image: http://i863.photobucket.com/albums/ab191...16x-2s.jpg]
Larry
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City: Clayton, NC
Nice set, Larry! Where did you find it?
I have a 116X chassis/speaker in my 116B tombstone, it is an outstanding radio!
Posts: 462
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I picked it up in eastern NJ a few weeks ago. It was on CL.
Larry
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I've hit a snag. There is a single .00011 Mfd, 400v paper cap in line to the lead to the detector (#77) tube. The radio appears to be working fine but I would hate to leave just one old cap in place. Anybody know where to get one of these (where it won't cost $15 postage for a $.50 cap ![Icon_smile Icon_smile](https://philcoradio.com/phorum/images/smilies/icon_smile.gif) )?
Thanks,
Larry
(This post was last modified: 03-28-2012, 12:37 PM by rocketeer.)
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(03-27-2012, 08:29 PM)rocketeer Wrote: I've hit a snag. There is a single .00011 Mfd, 400v paper cap in line to the lead to the first audio (#77) tube. The radio appears to be working fine but I would hate to leave just one old cap in place. Anybody know where to get one of these (where it won't cost $15 postage for a $.50 cap )?
Thanks,
Larry
I would make out a parts list of all the caps and carbon resistors and order those with the capacitor in question, it's only a matter of time until the ones inside the tar blocks fail even if it seems to be working at the moment.
I would try either Radio Daze or Bob's Antique radio supply for the caps, maybe Mauser if you want to get some resistors.
Regards
Arran
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I have already replaced all the other paper caps and the electrolytics. I only need that one paper cap, in an odd size. I tried all the usual sources and so far have not been able to find one.
Larry
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If you can handle a 100 pF 200v cap in that application, mouser has their p/n 581-SA102A101JAR (0.19 each) or 80-C410C101J2G (0.58 each) note they are ceramic. They can get 110 pF 400V poly caps at 68 cents each, but it is a long lead time.....And you have to order 3800 of them
If you want radial leads there are a ton o silver micas available at 500V
When I run into this I order a few and some .01 .047 etc for stock so I dont feel to bad about the freight.
John
Las Vegas, NV USA
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Thanks, it's a 400 volt spec but I don't think I'll need 3800 of them.
Larry
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(03-28-2012, 08:11 AM)rocketeer Wrote: Thanks, it's a 400 volt spec but I don't think I'll need 3800 of them. ![Icon_biggrin Icon_biggrin](https://philcoradio.com/phorum/images/smilies/icon_biggrin.gif)
Larry
110pf dipped silver mica caps are readily available and two of them fit nicely in a bakelite block as well.
Chuck
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Posts: 462
Threads: 40
Joined: Jun 2010
City: Lehighton
State, Province, Country: PA
I've replaced all the caps and all the electrolytics except the 4 small buggers inside the small can. As I went along I brought it up on the variac and tested it. Basically it sounds much like it did when I started except the hum is gone. At minimum volume she plays fine but as soon as the volume increases distortion appears and increase as the volume does. I swapped speakers with the parts set and there was no change. I'm hoping it's those last 4 lytics, when they arrive in the mail, but I'm not optimistic.
Having read up on the damage water can do to the dial I decided to try DeOxit D5 on a small area. It worked great so I did the entire dial. It cleaned up very nicely.
A couple corrosion spots on the chassis but I'll live with it. More to come.
[Image: http://i863.photobucket.com/albums/ab191...16x-12.jpg]
[Image: http://i863.photobucket.com/albums/ab191...16x-13.jpg]
Larry
(This post was last modified: 04-07-2012, 05:33 PM by rocketeer.)
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I finished replacing all the paper caps and electrolytics. It's got a weird problem and for now I'm going to shelve it and tinker with something a bit easier before I dig back into this over-crowded mining pit. Here's the story:
All paper caps replaced.
All electrolytics replaced.
All tubes tested, weak replaced.
All contacts everywhere cleaned.
Tuning condensor cleaned and lubed.
Replaced burned out bulbs.
What I have not done:
Replaced any resistors.
Touched any bakelite blocks.
Symptoms (using a variac):
90 volts - she plays and draws a little less than 1 amp.
105 volts - same but draws 2 amps.
122 volts (max) - same but now draws 3 amps.
What the heck is going on? I'm at a loss to understand why going from 90 to 122 volts triples the amperage draw. As I said, it's going to set a bit, but any insight would be appreciated.
Larry
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Hello, Larry: first check all your resistor values, incl the large wirewound.
Do you still have the incr in distortion as you incr volume? Could be a cathode bias issue in output circuit if so, BUT......
Re stuff of bakelite blocks is not that tough. You should replace these caps too as they too are 70+ years old. The mica caps are usually ok.
Any bad cap between B+ and ground can cause excessive current draw, but it could be something else.
Might be a good idea to re-check your previous work, just to be sure. Check to see if a lead or solder has been moved to the point that it is making ctc with ground.
BTW unclear if you did replace the can with the four caps.
Posts: 462
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Hi Tom, yep, I did replace those 4 little 'lytics. I'll be going over the rest of the chassis when I decide to jump back in. I just have a problem understanding why it draws less than an amp at 90 volts but 3 amps at 122 volts. Doesn't seem like it could be a short as that would cause the amps to climb as soon as voltage was applied, even as low as 60 volts.
You know that old saying "Careful what you wish for,"? I thought "Heck, I'll grab a little ol AA5, something easy." So, I grabbed an RCA clock radio my son had given me. I should know better. I was not expecting the clock to be hard-wired to the chassis so of course the clock has to come out at the same time. OK. Then I discover they used those insidious one-way metal push on clips tp hold it in place. Not 2, not 3 or 4, but 5 of the bloody things. Now I gotta worry about breaking those 50+ year old plastic tabs. Criminy, time to get out the rum and lemonade.
Larry
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Joined: Sep 2005
City: Evanston, IL
The condensers in bakelite blocks WILL leak and go "squirrely" at this age. Replace ALL the caps in them before you take something out with high current draw. Easy replacements. See the Service Tips section of my site for the pictorial procedure.
Chuck
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