Posts: 7,248
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Joined: Dec 2009
City: Roslyn Pa
>Will this work??
One way to find out. Don't think it will be an issue.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
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City: Lansdale
State, Province, Country: PA
Ok.. Guess if it doesn't work correctly I can then try to find something that will..
Thanks Terry..
Skip..
Posts: 7,248
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Joined: Dec 2009
City: Roslyn Pa
There's only a couple of things it might effect if in is too high. One would be the avc voltage/timing but since it's Am we are receiving it's going to be pretty negotiable. Would raise the gain of the 1st audio state. Again not a big deal. And may not track well ( all the control at one end of the turning radius). Other than that your home free!
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok all wired up now.. Power on tomorrow.. Wish me luck..
Skip
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
I'm pretty sure the vol ctl will work. Your AVC will shift. Might be nothing. If it affects things in a noticeable way, the vol ctl could be bypassed with a resistor so the paralleled result would be the same as initial value.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok Philco 89 Problems... Here we go again..
Completed wiring. Brought up slowly on Variac.. at 115 Volts about 400 Ma.. .. All Tubes light up..
But NO SOUND.. Not even a Hum.. Checked B+ voltage 366 Volts.. On pin 2 of output tube ( Plate) 337 Volts..
I did have the OSC and Det coils rewound.. Tubes check good.. The Field coil and output Transformer check good.
Help... What next to try?
Skip
Posts: 1,475
Threads: 69
Joined: Nov 2012
City: Kansas city, MO.
Skip, could be as simple as a miss wire some where. I would go ahead and retrace the circuit wiring first.
Posts: 7,248
Threads: 266
Joined: Dec 2009
City: Roslyn Pa
So whatdoyougot on pin 5 of the 42? Should be at ground (0v) and pin 4? Should be abt -20vdc. Oh and pin 3 abt the same as pin 2. Is heater in the 42 working?
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
(This post was last modified: 10-17-2018, 04:53 PM by Radioroslyn.)
Posts: 1,400
Threads: 70
Joined: Oct 2007
City: Linn Creek, MO
Skip, if you touch the center terminal of the volume control with your finger, do you hear a loud hum in the speaker?
Steve
M R Radios C M Tubes
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Will check all..
Thanks
Skip
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok , Here are the results.. If CTR of volume control touched NO sound ..
So I tried this.. I took out all the tubes and put them back in.. Now radio works.. Still almost NO noise but when I attached antenna the stations came in.. Needs alignment.. as not many stations at low end of band.. The volume control is flaky.. When you start to turn it up its gets loader until about 1/2 way then any farther the volume goes down and distorts.. See previous posts about control..
My guess is that I had a tube in wrong place..or maybe wasn't making good contact..
So now on the alignment and to see what I can do with the Volume control.. Anyone have alignment instructions?
Skip
Posts: 7,248
Threads: 266
Joined: Dec 2009
City: Roslyn Pa
Should be in rider's but check the code # to get the proper info.
> The volume control is flaky.. When you start to turn it up its gets louder until about 1/2 way then any farther the volume goes down and distorts.
Check your -voltage on pin 4 of the 42. If it's 0 you've got the ct of the power transformer grounded thru the -side of the filter cap.
Try another 75 tube.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
(This post was last modified: 10-17-2018, 10:16 PM by Radioroslyn.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Terry, OK I will check..
Skip
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
OK Pin 4 of 42 tube Reading -13.5 volts to ground..
Do not have another 75 or 42 tube I think.. But will look..
Skip
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Have a 75 tube But no 42 Tube..
Skip
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