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

Philco 91-221 (25 HZ) metal capacitor block 4989-K
#1

This is my first post.
http://www.nostalgiaair.org/pagesbymodel...013884.pdf

#56 in schematic

This is my first foray into the Philco bakelite blocks.  The regular ones go just fine.  I have the master key with the connections and the discontinued's, etc.  My problem is with the metal encased blocks, specifically 4989-k, noted as a 0.18mfd or, actually, two 0.09's.  There is no actual bakelite in this condenser bank.

Upon dissection of the old capacitor, there were 2 halves in the tar, separated by a paper insulator.  I could find no connection between the 2 halves.  There is no number on the metal case.

3 wires come out one end of the block. A bare ground wire to the metal case (subsequently grounded to chassis) was present on other end.

One half of the bank is wired to the filter choke and the rectifier tube.
The other half is wired to the electrolytics, the other wire to the ground as noted above.
Again, no apparent connection between the halves of the condenser block.

I have to admit my sophomoric level of understanding with regards to reading schematics.

My question regards rebuilding the block:
Should I re-wire it as I dissected it, using a 0.1 mfd in place of each side of the bank, or try to directly place them in parallel and somehow then make the connections?

Thank you, in advance.
Brian
#2

It does not matter.

First of I am not sure why you think #56 is a backelite inside the block. It is probably just a standalone backelite cap.
Better yet it was determinded the #56 cap is pretty useless and could be dropped altogether.

When I rebuild my blocks i twist all teh caps that go to GND together, solder it to teh case with a flexible wire, wrap in fish paper and push inside.
Those not grounded, just put out the wires the way they are shown on the sch.

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.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
A little light Saturday positive about our hobby in our feed... My new every Saturday video about antique radio equipme...RadioSvit — 02:12 PM
Model 70 Cabinet Trim
musar , Well if you have any more questions feel free to post away . Sincerely Richardradiorich — 08:56 PM
Model 70 Cabinet Trim
Although I have not made any cabinets or cabinet parts for a couple of years, I still have some parts left over, includi...Steve Davis — 06:26 PM
philcorepairbench.com - shadow-meter
Thanks Ron. But I can't find those articles.fenbach — 02:43 PM
Model 70 Cabinet Trim
Thank you, Gary. Before making my original post, I had clicked on "Steve Davis Cabinets" only to find that it...musar — 02:25 PM
philco predicta
Welcome to the Phorum, cgl18! I am not your resource for television repair, but lots of friendly help is available here...GarySP — 02:12 PM
Model 70 Cabinet Trim
Welcome to the Phorum, musar! You can send Steve Davis a private message (PM). The site is at the top of the Home page...GarySP — 02:09 PM
Model 70 Cabinet Trim
How do I contact him? The only contact information for him I could find when searching online was a telephone number th...musar — 10:38 AM
philco predicta
Hello, good afternoon, I would like to ask what the possible problem could be if I don't have an image on the screen. I ...cgl18 — 10:19 AM
Philco model 38 code 121 not receiving signal.
So one last question before I finish this radio. Regarding the speaker and output transformer. I salvaged the original o...Stormlord5500 — 09:31 AM

[-]
Who's Online
There are currently 660 online users. [Complete List]
» 1 Member(s) | 659 Guest(s)
Avatar

>