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

philco 90 ecap question
#1

Hello forum,
On my last (and first) set, all ecaps connected to ground so the direction of connection was straightforward. On the 90 (single 47) I'm now working on, the ecap (56), which consist of 2 ecaps (10uF and 6uF), connect to the rectifier filaments on one end and the other end connects to the transformer (and BC resistor). I'm a novice - I believe that the B+ line is the rectifier filament line and the B- line is the transformer/BC resistor line. So I assume that the ecaps negative end point toward the B- and positive to the B+ line...is this correct? Secondly, so I understand better, if the original part number 56 had 2 ecaps inside (10uF and 6uF) is it OK to substitute with a single 16uF (630V)? I appreciate any input you guys have-
Also, the schematic is attached - page 4 at the bottom
bdi


Attached Files
.pdf 90 single 47 Schematic.pdf Size: 851.01 KB  Downloads: 129
#2

A single capacitor won't work. Number 56, the input capacitor connects positive to the 80 filament and to the input of the filter choke, negative to the HV center tap. Number 57 connects positive to the output of the filter choke and negative to chassis ground.

Steve

M R Radios   C M Tubes
#3

Cap 56 has only one cap inside. It is either 6 uF for 50-60 cycle models, or 10 uF for 25-40 cycle models, it is not a dual cap. Same for the second filter cap 57.
#4

wow...I was wrong about everything. So the pos of the 56 to the transformer line, neg to the rectifier filaments. I was confused by the 6uF and 10uF specifications for the same cap since someone replaced the previous 57 cap with a 16uF cap. I have the 50-60 cycle model, so I should be back on track now. Thanks for the clarity guys. Please let me know if my summation of your info is incorrect.
#5

No, no, no...

Look here:

http://www.philcoradio.com/tech/images/90b.jpg

Positive of (56) to the junction of one leg of the 80 filament and the input lead of choke (55).

Negative of (56) to B- which is the high voltage secondary center tap, lead 12, and its junction with the bias or B-C resistor ( 58 ), terminal 1.

Now:

Positive of the output electrolytic (57) to the junction of the output lead of choke (55) and the speaker socket as indicated on the schematic.

Negative of (57) to chassis ground.

If you cannot read schematics or are having difficulty, STOP and learn to read schematics before proceeding. If you do not know what you are doing, you may fry a power transformer or other component, or worse yet, fry yourself...and we do not want that to happen.

http://www.antiqueradio.org/howfix.htm

--
Ron Ramirez
Ferdinand IN
#6

Thanks Ron - I believe I am reading them properly, however, the schematic I have (from NostalgiaAir) does not show the polarity of the ecaps like the one you provided. My last reply was accidentally incorrectly stated - my mistake. My original thread correctly stated my intention of matching pos to B+ and neg to B-, which matches your statement. Thanks for sending the schematic. I appreciate your input-
#7

Good. Icon_smile

And please do not misunderstand - I am definitely not trying to talk down to you - I'm only trying to help.

--
Ron Ramirez
Ferdinand IN




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Hi Cap'n Clock, Unfortunately, I do not have this radio.  This is a shame because this should be a good performer.  2A5...MrFixr55 — 06:48 AM
American Bosch Model 802 auto radio
I think it would come under either American Bosch or United American Bosch. American Bosch made sets for the American We...Arran — 05:53 AM
trying to identify this wire type
Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will ...georgetownjohn — 09:32 PM
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM

[-]
Who's Online
There are currently 6187 online users. [Complete List]
» 2 Member(s) | 6185 Guest(s)
AvatarAvatar

>