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

Philco 48-200 Clear but faint
#16

Well...I am looking at the Nostalgia website sch which I am not sure the one you have (do you have the link to the one you have)?

the 7A8 is the input tube.

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.
#17

So here's the problem, pin 6 is the control grid of the 50A5. If you connect the .22 to it and the chassis it passes most of the audio to ground. Remove that .22 from pin 6 and connect it from B- (- side of the filter) and the other end to the chassis as per the schematic. Leave the .01 and the 470k resistor.

Terry
#18

Ahhhh...my error I meant the 14A7 tube...not 7A8.
#19

The schematic with the 5OA5....

http://s000.tinyupload.com/index.php?fil...4261184648
#20

(07-11-2016, 11:58 AM)Radioroslyn Wrote:  So here's the problem, pin 6 is the control grid of the 50A5. If you connect the .22 to it and the chassis it passes most of the audio to ground. Remove that .22 from pin 6 and connect it from B- (- side of the filter) and the other end  to the chassis as per the schematic. Leave the .01 and the 470k resistor.

Terry

If I'm remembering correctly, I believe that all the filters are grounded to pin 4 of 14A7 (right next to where the .22 is/was attached now). There's a ton of wires and leads attached to pin 4. I'm impressed the manufacturers were able to do it. I do recall that it wasn't the pin the "troubleshooting" section of the schematic showed it to be.

This radio also had a three section cap with one (20 mfd) lead cut and a separate 20mfd installed. I assume it was a repair/replacement.

So attach .22 to pin 4 14A7 then to another convenient ground pin?
#21

Solution found. Someone had recapped this I the past. The .22 mfd cap I pulled and replaced was the problem. Checking the schematic, the cap was listed as a 22 MMFD cap. When I put a .0002 cap in there all was well.
#22

You need 0.00002uF (22pF) .

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: 2 Guest(s)
[-]
Recent Posts
Philco 16B Parts
The 16B's in the tombstone cabinet sport a 10 1/2" spkr vs the older cathedral sets which uses an 8". The p/p ...Radioroslyn — 12:58 AM
Philco 38-7 Oscillation
I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 11:16 PM
Philco 38-7 Speaker
I know that when I first started working on this radio, I did not even have a speaker. Once I finally found one it was n...tludka — 11:00 PM
Philco 60 Squealing
I seem to remember eliminating a squeal by changing the IF frequency by a few KHz. Not that you should put too much tru...fenbach — 08:48 PM
Philco 42-390, code 121 speaker
These speakers pop up on eBay regularly, even if at bloated prices. Honestly, have not seen many parts on swapmeets.morzh — 08:38 PM
Philco 38-7 Speaker
The put-put is not like the speaker problem.morzh — 08:29 PM
Mission Bell Model 19A Car Radio
Hello everyone,  As mentioned in my last post I was going to see if the vibrator / rectifier section could be persuaded...Antipodal — 08:21 PM
Philco 60 Squealing
Wondering if I did it backwards. If a coil was wound backwards, the oscillator would not work at all. Old school...Chas — 07:23 PM
Philco 38-7 Speaker
4-ohm speaker. Black, Green leads.tludka — 07:00 PM
Philco 42-390, code 121 speaker
#87 on the schematic.  This radio had a 8" Zenith  speaker attached to it when I got it. I do don't know the hist...Stevelog — 06:39 PM

[-]
Who's Online
There are currently 3945 online users. [Complete List]
» 3 Member(s) | 3942 Guest(s)
AvatarAvatarAvatar

>