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: 4 Guest(s)
[-]
Recent Posts
trying to identify this wire type
Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will ...georgetownjohn — 09:32 PM
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM
trying to identify this wire type
Greetings Phorum members, Hope you can help me identify this type of wire in the photo I have attached.  I am not sure ...georgetownjohn — 01:53 PM
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM

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

>