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

40-201 Output Xfmr Issues
#16

I found and corrected the problem I discovered as I was attempting IF alignment. I had the 1st. IF transformer secondary and tertiary windings swapped. I found it doing an ohm meter check. The secondary winding has about an 8-10 ohm resistance and the tertiary winding has less than 0.1 ohms resistance. I connected them to the correct points and the set quickly came into alignment. I found that with just this portion of alignment done, I already am getting signals on all bands and the push-buttons work but need adjusting for some local stations. This radio lives again!

Tomorrow or so I will get around to doing a complete alignment. For now I am happy. Christmas came early here!

Merry Christmas and a Happy, Healty and Prosperous New Year!

Joe
#17

As a followup to the output transformer installation and circuitry corrections, I installed the loop antenna, chassis and speaker in its cabinet yesterday. My evaluation of the unit is that although it has good sensitivity on all bands, the bass response of the replacement audio output transformer is woefully inadequate. It is only moderately better than a table model with a 4-5 inch speaker. I suspect that the original owner was very disappointed when he got his radio back from repair when the original transformer failed and had to be replaced. I plan to continue searching for either an original Philco transformer or find a better replacement with more iron in it. I had my misgivings about the replacement transformer the first time I spotted it.

Joe
#18

The hacked set is worse than a mouse home in the barn. Please post schematic or link so we can get started.




Users browsing this thread:
[-]
Recent Posts
Restoration of the Canadian General Electric A-87
Thanks for your help Michael. In fact, this video is only an intermediate result. Later I had to apply another tinting l...RadioSvit — 09:01 AM
Restoration of the Canadian General Electric A-87
Great job on the cabinet. PS. In the US notation, "kenotron" refers to specific type of tubes; we call re...morzh — 08:24 AM
Part numbers to model cross
This document has at least some tables of models and parts used. Example: Choke 32-7572, used in 604 radio. Search f...morzh — 08:19 AM
Restoration of the Canadian General Electric A-87
I also checked all the radio tubes on my Hickok 530 tube tester. The 5Z3 kenotron turned out to be faulty, all the other...RadioSvit — 08:02 AM
Restoration of the Canadian General Electric A-87
Well... While the varnish is drying up, I started repairing the chassis... Of course I started by replacing the pa...RadioSvit — 07:12 AM
Philco Model 38-7: what caps & resistors do fail typically?
Hello Martin, Welcome aboard our little community what great Model 38-7 Sincerely Richardradiorich — 12:30 AM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum Martin. I count about 9 paper caps, the 3 electrolytic caps and 2-Y2 safety caps to replace th...RodB — 09:44 PM
Part numbers to model cross
Jim, We have this index put together by Dale Cook but I don't think that is quite what you are looking for. The Parts...klondike98 — 09:37 PM
Philco Model 38-7: what caps & resistors do fail typically?
Yep the dim bulb test is OK but I'd definitely replace all those electrolytics before I did it. Since those #47 conden...klondike98 — 09:18 PM
Philco 42-345 Restoration/Repair
The resistor is a 2.2 Meg, it was the last one I hadn't replaced. The broadcast is coming in after replacing it.osanders0311 — 09:09 PM

[-]
Who's Online
There are currently 1144 online users. [Complete List]
» 1 Member(s) | 1143 Guest(s)
Avatar

>