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 42-345 Restoration/Repair
Today I've been reading through the site trying to learn more about this radio. I also soldered the lose power cord cabl...osanders0311 — 08:24 PM
Philco 610B oscillator wiring
Thanks David! I do have that same later prodution model 610 schematic. I've also studied the Philco service bulletins fo...Tubester — 08:12 PM
Philco 610B oscillator wiring
Some info from Beitmans says late production. David   David — 06:06 PM
Restoring Philco 96
Oh wow! Just found this thread.  Brings me back to early days on this phorum.  I did a 96 back in 2017.  Thread here: ...rfeenstra — 06:05 PM
Philco 610B oscillator wiring
Thanks for the replies. It's not the really the hum that I am after. Just trying to understand why only the shortwave ba...Tubester — 04:01 PM
Restoring Philco 96
70 and 90 are Superhets, but at least the 2x45 model of 90 uses the Plate detector (and so does 70). Also the Atwaters,...morzh — 03:28 PM
Restoring Philco 96
Morzh, Prayers for your mom. I am sure that there was enough pain living through the Holocaust as a child. I pray dail...MrFixr55 — 02:19 PM
Philco 610B oscillator wiring
Hi Dan, Divide and conquer. First off trry to differentiate between 60Hz and 120 Hz hum. 120 Hz hum has a higher pit...MrFixr55 — 01:49 PM
Restoring Philco 96
Yes, other than takin a toll on your back, they are undeed way more repair friendly than many other Philcos. To me, som...morzh — 01:04 PM
Philco 610B oscillator wiring
If the wires look like they were this way from the factory (very neat and very dull soldering joints), I'd leave them be...morzh — 12:58 PM

[-]
Who's Online
There are currently 1547 online users. [Complete List]
» 1 Member(s) | 1546 Guest(s)
Avatar

>