Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Missing Cap on 118
#1

I’m rewiring a Philco 118 highboy, due to damage to the wiring, using Philco service bulletin #194.
I am now rebuilding by-pass capacitor part 46 and am missing a 1mfd. capacitor. Part 46 has four (4) electrolytic caps in it, three (3) one mfd and one (1) two mfd.
I found three (3) caps and am missing one (1) cap, a one mfd cap.
Could the missing cap be mislabeled? Could the cap labeled 28, on the schematic, actually be part of 46?
28, on the schematic, is labeled 1 mfd; however, on the parts list it is listed as a compensating cap.
( I will try an attach a schematic, with the parts highlighted. )
#2

hopefully this link to the schematic will work. You may have to download it, I'm not sure. Sorry for the problem.


http://www.go2convert.com/converted/file/PX5HaamM


Icon_sad
#3

Joejoe,

Are you trying to locate them on the schematic? Because all 4 caps are in the same can.

Glenn
#4

Glenn, I believe that I figured this out late last night.

My schematic shows 46, by-pass condenser connections, on the lower left corner; however, if you search the schematic you will only find 3 caps labeled 46, when in fact there should be four capacitors labeled 46,on the schematic. One section, a 1 mfd section, is not labeled, or as in this case mislabeled, on the schematic.

I think that the schematic is wrong. The capacitor labeled 28 on the schematic is actually one part of 46 and is incorrectly labeled 28.

The capacitor labeled 29, on the schematic, is compensating cap 28 and the unlabeled 3000 mmfd, connected to the band switch, is p/n 29.

So far this is the third error that I found on this schematic and I really haven't started wiring the chassis.

Thanks Glenn.


FYI the other two errors on the schematic I'm using ( Philco service bulletin #194 ) are as follows:

1. On driver, tube 42, the plate and screen grid ( pins 2 and 3) are connected together, on the chassis but this does not show up on the schematic.

2. The screen grids (pins 3), of the RF and IF amps, tubes 78, are floating and not connected to the grid supply, composed of p/n 67, 68 and of course capacitor 46.




Users browsing this thread:
[-]
Recent Posts
Philco 610B oscillator wiring
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM
HiFi (Chifi) tube amp build - but my own design.
Tim; I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM

[-]
Who's Online
There are currently 1583 online users. [Complete List]
» 1 Member(s) | 1582 Guest(s)
Avatar

>