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

38-690 Code 125
#28

So as I now understand it, your oscillator frequency is correct at 600 kc, 25 kc high at 760, 40 kc high at 950 and 50 kc high at 1200 kc. 

With this further info and the fact you checked and aligned your IF at 470 kc again, looks like the IF is not at fault since the tracking offset is not constant but varies from 0 to 50 kc.

This points to an oscillator error as you tune higher in frequency. The tuning capacitance is too low as you go higher in frequency. Check the connections to the main tuning cap as each section has a split stator where both stators are used in parallel on the broadcast band.

Could still be caused by the AFC circuit since the 6N7 control tube is always in circuit even if you short out the AFC with the switch. I would double check any work you did in the oscillator and AFC sections of the RF section.


Messages In This Thread
38-690 Code 125 - by RGK20m3 - 11-24-2021, 08:26 PM
RE: 38-690 Code 125 - by klondike98 - 11-24-2021, 09:01 PM
RE: 38-690 Code 125 - by RGK20m3 - 11-26-2021, 05:41 PM
RE: 38-690 Code 125 - by klondike98 - 11-26-2021, 06:21 PM
RE: 38-690 Code 125 - by RGK20m3 - 11-26-2021, 10:29 PM
RE: 38-690 Code 125 - by RGK20m3 - 12-02-2021, 07:35 PM
RE: 38-690 Code 125 - by morzh - 12-02-2021, 08:09 PM
RE: 38-690 Code 125 - by Ron Ramirez - 12-02-2021, 08:58 PM
RE: 38-690 Code 125 - by morzh - 12-02-2021, 09:02 PM
RE: 38-690 Code 125 - by radiorich - 12-02-2021, 10:01 PM
RE: 38-690 Code 125 - by Ron Ramirez - 12-02-2021, 11:41 PM
RGK20m3 - by RGK20m3 - 12-05-2021, 06:03 PM
RE: 38-690 Code 125 - by David - 12-05-2021, 07:19 PM
RE: 38-690 Code 125 - by klondike98 - 12-09-2021, 08:08 PM
RGK20m3 - by RGK20m3 - 12-10-2021, 02:54 PM
RE: 38-690 Code 125 - by Mondial - 12-10-2021, 06:42 PM
RE: 38-690 Code 125 - by RGK20m3 - 12-10-2021, 07:15 PM
RE: 38-690 Code 125 - by morzh - 12-10-2021, 07:27 PM
RE: 38-690 Code 125 - by Mondial - 12-10-2021, 07:40 PM
RE: 38-690 Code 125 - by mikethedruid - 12-10-2021, 08:01 PM
RGK20m3 - by RGK20m3 - 12-10-2021, 10:09 PM
RGK20m3 - by RGK20m3 - 12-11-2021, 12:14 PM
RE: 38-690 Code 125 - by Mondial - 12-11-2021, 01:58 PM
RGK20m3 - by RGK20m3 - 12-11-2021, 05:41 PM
RE: 38-690 Code 125 - by Mondial - 12-11-2021, 06:48 PM
RE: 38-690 Code 125 - by tbone - 12-12-2021, 02:27 PM
RGK20m3 - by RGK20m3 - 12-13-2021, 08:24 PM
RE: 38-690 Code 125 - by Mondial - 12-14-2021, 10:22 AM
RE: 38-690 Code 125 - by morzh - 12-14-2021, 12:40 PM
RE: 38-690 Code 125 - by Ron Ramirez - 12-14-2021, 01:40 PM
RE: 38-690 Code 125 - by RGK20m3 - 12-14-2021, 03:25 PM
RE: 38-690 Code 125 - by morzh - 12-14-2021, 03:35 PM
RE: 38-690 Code 125 - by Mondial - 12-14-2021, 04:06 PM
RE: 38-690 Code 125 - by Ron Ramirez - 12-14-2021, 04:42 PM
RGK20m3 - by RGK20m3 - 12-14-2021, 10:32 PM
RE: 38-690 Code 125 - by Ron Ramirez - 12-14-2021, 10:58 PM
RGK20m3 - by RGK20m3 - 12-15-2021, 09:01 AM
RGK20m3 - by RGK20m3 - 12-15-2021, 11:55 AM
RE: 38-690 Code 125 - by Mondial - 12-15-2021, 03:02 PM
RGK20m3 - by RGK20m3 - 12-15-2021, 05:14 PM
RE: 38-690 Code 125 - by RGK20m3 - 01-02-2022, 06:05 PM
RE: 38-690 Code 125 - by Greg - 01-02-2022, 06:42 PM
RE: 38-690 Code 125 - by Mondial - 01-02-2022, 07:59 PM
RGK20m3 - by RGK20m3 - 01-03-2022, 12:36 PM
RE: 38-690 Code 125 - by Mondial - 01-03-2022, 01:43 PM
RGK20m3 - by RGK20m3 - 01-04-2022, 09:12 AM
RE: 38-690 Code 125 - by Mondial - 01-04-2022, 12:21 PM
RE: 38-690 Code 125 - by RGK20m3 - 01-04-2022, 07:01 PM
RGK20m3 - by RGK20m3 - 01-05-2022, 12:36 PM
RE: 38-690 Code 125 - by Mondial - 01-05-2022, 01:56 PM
RGK20m3 - by RGK20m3 - 01-05-2022, 02:57 PM
RE: 38-690 Code 125 - by Mondial - 01-05-2022, 05:59 PM
RGK20m3 - by RGK20m3 - 01-06-2022, 07:39 PM
RE: 38-690 Code 125 - by Mondial - 01-07-2022, 11:44 AM
RE: 38-690 Code 125 - by RGK20m3 - 01-07-2022, 01:03 PM
RGK20m3 - by RGK20m3 - 01-07-2022, 01:32 PM
RE: 38-690 Code 125 - by Mondial - 01-07-2022, 01:49 PM
RGK20m3 - by RGK20m3 - 01-07-2022, 02:31 PM
RGK20m3 - by RGK20m3 - 01-29-2022, 01:25 PM
RE: 38-690 Code 125 - by Brad Winder - 02-02-2022, 08:30 PM
RGK20m3 - by RGK20m3 - 02-04-2022, 07:41 PM
RE: 38-690 Code 125 - by Brad Winder - 02-06-2022, 02:53 PM
RE: 38-690 Code 125 - by RGK20m3 - 02-07-2022, 11:26 AM
38-690 RF Alignment - by RGK20m3 - 12-09-2021, 02:54 PM
RE: 38-690 RF Alignment - by morzh - 12-09-2021, 04:16 PM
RE: 38-690 RF Alignment - by RGK20m3 - 12-09-2021, 04:40 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
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
462ron
It’s on the bottom of the homepage of our Philcoradio.com homepage! Ron462ron — 07:20 AM
Model 70 Cabinet Trim
Steve might have some trim left. Not sure he is making anything.morzh — 06:12 AM
Model 70 Cabinet Trim
Hello musar, First all welcome to the forum and yes that is true that steve stopped making trim . Sincerely Richar...radiorich — 12:13 AM
Model 70 Cabinet Trim
I have recently come into possession of a Model 70.  The trim around the base needs to be replaced.  If this were years ...musar — 12:07 AM
philcorepairbench.com - shadow-meter
Anyone know of a way to recover these files from the repair bench? Thanks. fenbach — 11:16 PM
Philco model 38 code 121 not receiving signal.
That's true. Of course If I were to get a vtvm I'd probably have to sink money in to it to get it working right. Probabl...Stormlord5500 — 08:44 PM
Philco model 38 code 121 not receiving signal.
A DMM is good enough. One rarely has to measure indictance, but if you do, short of getting a serious LCR meter (I hav...morzh — 07:35 PM
Testing a speaker and output transformer Trutone A2-G
You guy's are right on. I found a broken wire on the speaker plug that I replaced and all is well now. Have better volu...murf — 03:43 PM
Philco model 38 code 121 not receiving signal.
I need to get a vtvm. I think that little component tester is just more accurate. Plus it shows the inductance which is ...Stormlord5500 — 03:07 PM

[-]
Who's Online
There are currently no members online.

>