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 restoration
#25

It turned out that there was an open 1,000 ohm resistor in the circuit feeding B+ to the RF and mixer tubes, number 64 on the schematic:

[Image: http://i269.photobucket.com/albums/jj77/.../037-2.jpg]

I've got one of the three chassis sections done, and it plays much better now, receiving many stations. I suspect the tweeters are not working, but I'll get to that issue after finishing the radio chassis work. The problem may even be in the radio chassis.

The guy who previously worked on it did not bother to replace 0.02 mfd capacitors with the proper value, instead using 0.01mfd units, even though he could have put two of those in parallel ...

I'm going though and replacing the resistors and correcting capacitor errors.

Web site: http://www.masekconsulting.net
Radio Photos: http://www.photobucket.com - album id FStephenMasek


Messages In This Thread
Philco 38-690 restoration - by FStephenMasek - 04-18-2011, 09:30 PM
RE: Philco 38-690 restoration - by FStephenMasek - 04-13-2013, 12:47 PM
RE: Philco 38-690 restoration - by FStephenMasek - 04-13-2013, 09:16 PM
RE: Philco 38-690 restoration - by morzh - 04-13-2013, 09:22 PM
RE: Philco 38-690 restoration - by FStephenMasek - 02-17-2014, 12:35 PM
RE: Philco 38-690 restoration - by morzh - 02-17-2014, 12:43 PM
RE: Philco 38-690 restoration - by FStephenMasek - 02-17-2014, 10:13 PM
RE: Philco 38-690 restoration - by morzh - 02-17-2014, 10:16 PM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 12:04 AM
RE: Philco 38-690 restoration - by morzh - 06-22-2014, 10:56 AM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 01:01 PM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 07:18 PM
RE: Philco 38-690 restoration - by morzh - 06-22-2014, 08:44 PM
RE: Philco 38-690 restoration - by gregb - 06-22-2014, 08:47 PM
RE: Philco 38-690 restoration - by PhilcoJohn - 06-23-2014, 05:47 PM
RE: Philco 38-690 restoration - by morzh - 06-23-2014, 05:53 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-06-2014, 01:40 PM
RE: Philco 38-690 restoration - by morzh - 07-06-2014, 02:13 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-06-2014, 02:46 PM
RE: Philco 38-690 restoration - by morzh - 07-06-2014, 02:51 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-10-2014, 04:32 PM
RE: Philco 38-690 restoration - by morzh - 07-10-2014, 05:32 PM
RE: Philco 38-690 restoration - by FStephenMasek - 11-06-2014, 01:27 AM
RE: Philco 38-690 restoration - by sam - 11-06-2014, 03:57 AM
RE: Philco 38-690 restoration - by 462ron - 11-06-2014, 01:13 PM
RE: Philco 38-690 restoration - by klondike98 - 11-06-2014, 02:08 PM
RE: Philco 38-690 restoration - by morzh - 11-06-2014, 02:35 PM
RE: Philco 38-690 restoration - by FStephenMasek - 11-11-2014, 12:57 PM
RE: Philco 38-690 restoration - by morzh - 11-11-2014, 01:17 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 10:07 AM
Re: Philco 38-690 restoration - by FStephenMasek - 04-19-2011, 12:59 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 02:00 PM
Re: Philco 38-690 restoration - by FStephenMasek - 04-19-2011, 02:35 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 02:47 PM
Re: Philco 38-690 restoration - by FStephenMasek - 04-20-2011, 10:47 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-21-2011, 07:41 AM
Re: Philco 38-690 restoration - by FStephenMasek - 04-26-2011, 10:06 PM



Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
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
Philco model 38 code 121 not receiving signal.
I use a pair of Mastercraft brand DMMs from Canadian Tire, from what I read most of those DMMs use the same main chip re...Arran — 02:36 PM
Philco model 38 code 121 not receiving signal.
Thank you sir. Yes I feel good and also relieved because this one's been weighing on me a bit.Stormlord5500 — 11:18 AM
Philco model 38 code 121 not receiving signal.
It feels good don't it? Good luck on the rest.Paul Philco322 — 11:06 AM
Philco model 38 code 121 not receiving signal.
I've reinstalled the coil. Now IT'S ALIVE!!!!!! I fired up my TinySA on signal generator mode and set it to 1400Kc and ...Stormlord5500 — 11:01 AM
Philco model 38 code 121 not receiving signal.
Yes, Walmart, right up there with Fluke.RodB — 11:00 AM
PT 6 chassis screws size???
it certainly won't be metric! SAE threads were all that was known then. Take care, - GaryGarySP — 10:58 AM
Philco model 38 code 121 not receiving signal.
I think this thing is way more accurate than my Walmart DMM. :DStormlord5500 — 08:19 AM
Philco model 38 code 121 not receiving signal.
Thankyou for the kind words sir. I double checked it with my component tester and it read 2.7 ohms at .02mH.Stormlord5500 — 08:14 AM

[-]
Who's Online
There are currently 2776 online users. [Complete List]
» 3 Member(s) | 2773 Guest(s)
AvatarAvatarAvatar

>