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 37-84--no sound
#16

(04-22-2012, 07:56 PM)7estatdef Wrote:  Half a meg is way too high. Volume is the wrong value. What you need is something around 10 to 30 k. This should work fine.
Terry
ps Did you get your -15v back on pin5 of the 6K6 which should be a 6F6

Here is latest update. I changed volume control to 25K. Volume was very low again. Then the AC switch on/off malfunctioned. I put back on the old VC switch. For some reason, I can't align this set. I get both RF and AF coming thru, but can't seem to get passed output meter reading. Instructions say to put meter on plate and cathode of output tube and set output meter to 0-30 volts. I get 250 volts when I do that. When I hooked up to voice coil, I got loud static! Confused???
Another issue is that radio works...when I keep the metal adjustment tool on the screw of the first trimmer. When I pull the tool off, I lose the signal??? Any thoughts greatly appreciated.
#17

(05-08-2012, 10:45 AM)sjhs1962 Wrote:  
(04-22-2012, 07:56 PM)7estatdef Wrote:  Half a meg is way too high. Volume is the wrong value. What you need is something around 10 to 30 k. This should work fine.
Terry
ps Did you get your -15v back on pin5 of the 6K6 which should be a 6F6

Here is latest update. I changed volume control to 25K. Volume was very low again. Then the AC switch on/off malfunctioned. I put back on the old VC switch. For some reason, I can't align this set. I get both RF and AF coming thru, but can't seem to get passed output meter reading. Instructions say to put meter on plate and cathode of output tube and set output meter to 0-30 volts. I get 250 volts when I do that. When I hooked up to voice coil, I got loud static! Confused???
Another issue is that radio works...when I keep the metal adjustment tool on the screw of the first trimmer. When I pull the tool off, I lose the signal??? Any thoughts greatly appreciated.

Something really wrong here. I use a VTVM to measure modulated AC voltage across secondary (speaker) winding of the output stage. Digital meters will drive you nuts when trying to do alignment.

Also use an isolation transformer when working on transformerless sets and of course update your signal generator to 3-wire grounded state.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
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
Philco Battery-WWII vintage
Hello Bob, What Amazing find! Sincerely Richardradiorich — 10:19 PM
Testing a speaker and output transformer Trutone A2-G
Hi Murf, Do this: Monitor between ground and one plate of the rectifier while playing the radio.  Do the same with ...MrFixr55 — 09:51 PM
Philco Battery-WWII vintage
Mike; I take it that Soviet cars did not come equipped with block heaters, hence the hot oil change? Where I lived in...Arran — 08:42 PM
Philco 42-345 Restoration/Repair
The more the better. (Within reasonable limits.) 2-5 times more is no problem in this case.Vlad95 — 03:50 PM
Philco 42-345 Restoration/Repair
Thanks, RodB and Vlad95, I was mainly trying to figure out this capacitor to locate a replacement, Vlad thank you for...osanders0311 — 03:44 PM

[-]
Who's Online
There are currently 907 online users. [Complete List]
» 3 Member(s) | 904 Guest(s)
AvatarAvatarAvatar

>