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

Unknown Tubes on a 42-327
#8

Hey Ron,

The loop antenna is disconnected. The wires were cut when I bought the radio, but all I'd need to do is reconnect it. I think all I touched was the inside of the chasis, but then, honestly, the oaf in me may have touched something else. I thought it was the chasis but I can't find any bad solders or bare wires in direct contact with the chasis. I also can't find any voltage on the chasis with the multimeter. No AC or DC. I don't really know what happened.

I also meant to say that rewire-ing the whole radio was something I'm NOT terribly confident I can do well. I'll try to dig out my camera and put some pictures up of what I have and I'll reconnect the antenna and see what happens. I haven't been shocked from the chasis since my last jolt (thumbs up) so maybe I just touched something else and thought it was the chasis. Yet another lesson learned. At least I've been smart enough to only touch the energized radio with one hand at a time, with the other hand behind my back. I guess I did learn something from that electricity lab in college.

Also, the 170vdc was directly from the wires that would go into the speakers. The schematic says it's the BC (broadcast coil, I think), directly from the speaker transformer. The speakers picked up the loud buzz too.

I just thought of something... if the speaker transformer was shorted could a high voltage be sent to the speaker and produce a steady voltage? Maybe a loud buzzing? It wouldn't produce 170vdc, but it could at least produce something pretty steady. How often do transformers go bad in these old sets?
... I just measured the resistance on the secondary winding. The secondary winding has infinite resistance (it should be about 0 ohms, right?) and between the black wire on the secondary side and the primary winding I had 0 ohms (indicating a short in the transformer, right). Does this mean I'm looking for a new transformer? Also, the primary winding read a resistance of ~280 ohms, per the schematic.

I'm in columbus, OH. I'm teaching Naval engineering and Weapons design to the Naval ROTC midshipmen at OSU and I'm hopefully going to get accepted into the electrical engineering program. I can work my way through transistors, but I don't know much about these old tubes... the technology of these tube radios is absolutely amazing. Much cooler than transistors. I'd definitely love to find someone who can help me bring this old radio back to life.

Ron, how'd you get so good at these radios? I'm thankful you and the rest of the radio hobbyists are good with these sets. Hopefully one day I'll be answering questions instead of leeching off you Icon_smile Thanks for your help.

-Brandon


Messages In This Thread
Unknown Tubes on a 42-327 - by regel_1999 - 03-04-2011, 11:23 PM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-05-2011, 11:31 AM
Re: Unknown Tubes on a 42-327 - by Carl Travis - 03-05-2011, 11:44 AM
Re: Unknown Tubes on a 42-327 - by BILL - 03-05-2011, 01:46 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-05-2011, 03:28 PM
42-327 with grounds - by regel_1999 - 03-06-2011, 03:19 PM
Re: 42-327 with grounds - by Ron Ramirez - 03-06-2011, 03:45 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-06-2011, 07:26 PM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-06-2011, 07:51 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-06-2011, 08:06 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-06-2011, 08:35 PM
Re: Unknown Tubes on a 42-327 - by DeckApe - 03-07-2011, 02:11 AM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-07-2011, 09:50 AM
Re: Unknown Tubes on a 42-327 - by 7estatdef - 03-07-2011, 10:45 AM
Re: Unknown Tubes on a 42-327 - by Glenn Roberts - 03-07-2011, 11:24 AM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-08-2011, 12:49 PM
Re: Unknown Tubes on a 42-327 - by Glenn Roberts - 03-08-2011, 04:38 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-08-2011, 04:46 PM
Re: Unknown Tubes on a 42-327 - by 7estatdef - 03-09-2011, 05:52 PM
Re: Unknown Tubes on a 42-327 - by Ed Locker - 03-10-2011, 10:03 AM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-10-2011, 07:29 PM
Re: Unknown Tubes on a 42-327 - by rplackey - 03-14-2011, 12:36 AM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-14-2011, 10:09 AM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-16-2011, 02:47 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-16-2011, 06:09 PM
Re: Unknown Tubes on a 42-327 - by rplackey - 03-16-2011, 10:15 PM
Re: Unknown Tubes on a 42-327 - by Ron Ramirez - 03-17-2011, 11:38 AM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-17-2011, 12:08 PM
Re: Unknown Tubes on a 42-327 - by rplackey - 03-17-2011, 01:32 PM
Re: Unknown Tubes on a 42-327 - by regel_1999 - 03-17-2011, 08:39 PM



Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Philco model 38 code 121 not receiving signal.
Thanks Arran. Yeah this plastic is pretty thin. It's a little thinner than the original stuff. It kinda reminds me of p...Stormlord5500 — 04:37 PM
Testing a speaker and output transformer Trutone A2-G
The equivalent of one short turn is basically the same as that of a shorted load. If it is the primary's turn, then the ...morzh — 03:53 PM
Testing a speaker and output transformer Trutone A2-G
I've never had an output transformer become shorted, the failure mode is usually an open primary, or in a center tapped ...Arran — 03:52 PM
Philco model 38 code 121 not receiving signal.
As long as the plastic sheeting isn't too thick, I think that the thickness of photographic film would be just about rig...Arran — 03:19 PM
Philco model 38 code 121 not receiving signal.
Well why not! :lol:Stormlord5500 — 03:14 PM
Philco model 38 code 121 not receiving signal.
Good luck next thing you know you will be winding coils just for the fun of it. DavidDavid — 11:29 AM
Testing a speaker and output transformer Trutone A2-G
morzh Short-circuited turns can be considered as a half-dead transformer. But on this case transformer will hot and s...Vlad95 — 11:01 AM
Testing a speaker and output transformer Trutone A2-G
I am not sure how a transformer could be weak. It could be inadequate, but only when you replace the original with somet...morzh — 09:56 AM
Philco model 38 code 121 not receiving signal.
Good news everyone! I think I have found everything I need for rewinding the antenna coil primary. I found some pla...Stormlord5500 — 09:40 AM
Philco Battery-WWII vintage
My younger sister went to SUNY Plattsburg NY, (BS, MS, RN) in the late 1970sabout 10 min from the Northern NY / Canada b...MrFixr55 — 07:59 AM

[-]
Who's Online
There are currently 1760 online users. [Complete List]
» 3 Member(s) | 1757 Guest(s)
AvatarAvatarAvatar

>