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Philco-18 problem
#1

When I bought this radio from a radio person, he explained away the following note as "probably caps": 80 tube overheats, do not energize until problem is found. So I took out the 80, and did some voltage checks. The voltages to the 80 were right on. Filaments to the other tubes OK. Field coil OK, choke OK. So I stick the 80 in and at around 80 volts, there are little sparks on the 80 tube socket (from underneath) and I quickly shut down. The 80ST shows shorts and no filaments.. I hadn't checked it before this. Now, before I start the lengthy (but enjoyable Icon_wink ) recap, do my initial transformer checks rule out a transformer problem? Anything else to check first? Suspects?

What schematic do I want to be looking at? This chassis has a band switch; the on/off is with the volume. The electrolytics don't match up with 18 schematic. For example, I don't have part #s 59 & 60 (8uF & 10uF and 8uF), I have a 20/20/20 can.
#2

Bad 80 tube socket? This has been known to happen in Philcos of this vintage.

If it has two bands (AM and the "police" band), on-off with the volume control, then it is the early 18 - not the later Code 124 (AM only) version.

--
Ron Ramirez
Ferdinand IN
#3

Quote:then it is the early 18


Is this something that I have to get from The Philco Repair Bench?
#4

Ah, I see what you mean - the early 18 isn't at Nostalgia Air.

Well, if you want good, clear, readable schematics with all production change notes, etc., then - yes.

--
Ron Ramirez
Ferdinand IN
#5

Well worth the 7.00 from Chuck.
#6

Quote:Bad 80 tube socket? This has been known to happen in Philcos of this vintage.

Electrolytics this time.

Quote:Well worth the 7.00 from Chuck.

Check went in the mail today.
#7

DKinYORKpa Wrote:
Quote:Bad 80 tube socket? This has been known to happen in Philcos of this vintage.

Electrolytics this time.

Okay, just trying to help...good luck...you may need it.

--
Ron Ramirez
Ferdinand IN
#8

Quote:Okay, just trying to help...good luck...you may need it.

I love your help! Now, why may I need good luck??????
#9

If you saw sparks in or under that socket and it is a wafer style, then you better keep an eye on it after you are done. Any arc will burn a trace between the layers of the wafer resulting in a HV short that just gets worse.
#10

^^^
And that was the point I was trying to make, DK! Phlogiston is 100% correct.

Now, let's all go put some extra Chivas Regal in our New Year's drink for this evening and have a nice night.

--
Ron Ramirez
Ferdinand IN
#11

I still have a transformer to wind. Will Chivas Regal help - you know it will!




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