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Almost done with recapping (two tubulars left) and all but two resistors have been replaced. The tone ctl has been rebuilt.
Now the volume pot is problematic. While end to end resistance is correct, there is a dead zone. I cleaned and lubed it but I will be looking for a new one.
The switch is also problematic though after some exercise it makes and with some current it will self clean but it is one of those covered with a riveted plate so no cleaning possible.
This Philco has the tuhular caps with the rolled up ends, so just pulling the guts out is not possible, so I cut tbe rolled edges off. Never saw those before.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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(06-12-2016, 10:21 PM)morzh Wrote: Almost done with recapping (two tubulars left) and all but two resistors have been replaced. The tone ctl has been rebuilt.
Now the volume pot is problematic. While end to end resistance is correct, there is a dead zone. I cleaned and lubed it but I will be looking for a new one.
The switch is also problematic though after some exercise it makes and with some current it will self clean but it is one of those covered with a riveted plate so no cleaning possible.
This Philco has the tuhular caps with the rolled up ends, so just pulling the guts out is not possible, so I cut tbe rolled edges off. Never saw those before.
Mike;
The way you get those caps with a rolled over end apart is to heat the body of the cap, then put one end down over a small diameter mechanic's socket, then push down and the guts of the cap should pot out of the top. This was the style that RCA used to use, except with those you usually don't have to heat them the guts will just push or pull out by the leads. The same trick would with those axial lead electrolytics with the cardboard sleave over metal. Then after you restuff the cap you roll the open end over again.
Regards
Arran
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Arran
I am not sure I understood the part with the socket.
Wish I knew before. I usually heat the body and simply pull a lead, and then pull another, and the guts just follow.
In any case, with cut off ends these caps look normally, same as the other ones without the rolled-up ends when potted with hot glue.
The only thing I should do probably is to buy the colored hot glue, this will look better.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Question:
If anyone knows.
I need to figure out the sizes that fit my 118.
Out of the following:
PHILC 67-0032 350K W/TAP, SPEC SHAFT REQ...
PHILC 67-0042 350K, TAP 60K, W/SW, 3/16d SF
PHILC 67-0003 350K W/TAP, W/CW SW,SPEC SFT.
EX-STAT TP101 350K, TAP @75K, USES "A" SW
PHILC 33-5535 350K, 2 TAPS, MODEL 48-1274.. (not sure where the tap is ohm-wise)
PHILC 3354252 350K W/TAP W/SW, SHAFT SAVER.
PHILCO 670042 350K W/60K TAP W/SW,3/16DIA S
PHILCO/CENTRA 350K, TAP 70K, W/SW, 2 5/8flt
Or if someone is willing to sell me either PN# 33-5069 (vol ctl from 18 ) or 33-5024 (from 118 ).
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 06-13-2016, 08:21 PM by morzh.)
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(06-13-2016, 09:57 AM)morzh Wrote: Arran
I am not sure I understood the part with the socket.
Wish I knew before. I usually heat the body and simply pull a lead, and then pull another, and the guts just follow.
In any case, with cut off ends these caps look normally, same as the other ones without the rolled-up ends when potted with hot glue.
The only thing I should do probably is to buy the colored hot glue, this will look better.
Mike;
A socket from a socket set, like a mechanic would use, a 1/4 or smaller one is what you might need for a paper cap, larger for an electrolytic. You place the socket on a table, then place the end of the capacitor on top, grab the body of the cardboard tube and pull it or push it down over the socket, the guts of the capacitor will pop out of the top end if everything is working right. Sometimes you will need to heat it up with a heat gun first though, in which case grab the cardboard tube with a rag so you don't burn yourself.
Regards
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Oh...got it. So you pretty much force the guts out so they would unwrap the opposite end.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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So...no one chimes in with advice on #19 post with question on the pots?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Powered it up tonight.
No singing. IF signal goes through nicely if applied to the 6A7 grid but barely gets through the 1st RF 78. Both transformers, the antenna snd the 1st RF seem to be fine, the 78 is good. Tomorrow will see if the absence of the shadow meter is at fault, will put 1K resistor in parallel to the shadow meter bypass.
Well, at least the audio's good and the oscillator too.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Well, still struggling. Thing is, cannot devote real time right now to it, the house full of people and so things keep popping up, like helping making a frame for the picture that they brought or ...or....so haven't really been able to crack this one yet.
I realized the IF signal gets suppressed by the first tuned circuit. An RF signal that corresponds to the dial position does get through. But not very strong. Whereas the IF signal applied to the 6A7 grid does get through very loudly. No stations. Yet.
Voltages seem fine.
The antenna and the second RF transformer (the RF 78 load) seem fine, at least continuity-wise.
So, will have to start looking at values (all replaced, caps and resistors); I do not think this is the AVC misbehaving (I did add that 1K resistor in parallel to the shadow meter bypass to emulate the shadow meter that I have not put in yet) but will check it. All tubes are fine, and the 78 RF has been replaced, and re-checked........
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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So it was the AVC. I accidentally connected cap #17 to the bottom pin of the RF xfmr #12 instead of the middle pin.
No wonder it attenuated the heck out of everything.
I walked down the AVC circuit and noticed the 2M and 70K resistor, where they connect to the coil, had no cap connected. That was the clue
Anyways, it plays very well now, the sound is really booming.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Put back the shadowgraph; seems to work.
Need to put in the new volume regulator I got from Mark.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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I aligned it tonight. Pkenty of stations on BC and SW.
As a final act of defiance it started crackling when I plugged it into 120V, and then kept doing it at 110V, stopping it at 100V. Changing the 80 tube fixed it.
I think I will !eave it this way.
PS. It lacks the chassis bolts. Held by those brackets, but. no bolts. May have to buy them.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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