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 38-690 Oscillator Not Working?
#1

I have strong audio signals and strong IF signals. I am receiving no stations at all.

The local oscillator does not seem to be working. Oscillator voltages are as follows:
Pin 3 - 191.8 VDC
Pin 4 - 93.0 VDC
Pin 5 - 1.58 VDC
Pin 6 - 195.5 VDC
Pin 8 - 2.53 VDC
Grid Cap - 0 VDC

The mixer voltages are as follows:
Pin 3 - 238.1 VDC
Pin 4 - 99.7 VDC
Pin 5 - 1.58 VDC
Pin 6 - 99.7 VDC
Pin 8 2.53 VDC
Grid Cap - 0 VDC

Shouldn't the pin 5 of the oscillator grid measure a large negative voltage? Does the OSC CONT tube
have control over the oscillator?

Thanks for any suggestions and help.
nv3g
Oscar


Messages In This Thread
Philco 38-690 Oscillator Not Working? - by NV3G - 04-02-2019, 07:53 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 91 code 221
Chassis grounds thru rivets is another good place to look. Oh and the stator screws on the tuning cap where the leads at...Radioroslyn — 08:11 AM
Philco 91 code 221
Dirty tube pins and socket, cold solder joint, stray tiny strand of wire, clean the entire area around the oscillator tu...RodB — 08:43 PM
Philco 91 code 221
I have been restoring one of these sets and switched it on yesterday. It didn't exactly spring into life, but after a co...Philconut — 08:26 PM
Philco 50-925 antenna connections
That's super. Glad to hear you figured it out. Paul.Paul Philco322 — 11:11 AM
Philco 50-925 antenna connections
Hello Keith, great news !! Sincerely Richardradiorich — 02:14 AM
Philco 50-925 antenna connections
Finally, got the antenna fixed (repaired some broken wires) and have the radio playing. I've got four different schemat...keith49vj3 — 09:38 PM
1949 Motorola 5A9M
Bob, Nice radio.  I’ve not seen one before.  Keep us updated!Joe Rossi — 07:56 PM
Phioco 90 Power Transformer Wire Colors
Thanks for adding that information.klondike98 — 06:09 PM
Phioco 90 Power Transformer Wire Colors
Although I have used this site as a resource for a number of years this is my first post.   I am restoring a Model 90 si...vincer — 05:02 PM
My collection presentation
There is a complete instruction how to solve your problem. One piece of advice - be careful with the low-voltage capacit...Vlad95 — 09:32 AM

[-]
Who's Online
There are currently 760 online users. [Complete List]
» 2 Member(s) | 758 Guest(s)
AvatarAvatar

>