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 Post subject: Unable to Rock
PostPosted: Feb Tue 10, 2004 10:50 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 117
Location: Brookeland, Tx USA
Have been doing a realignment of my 41-629 and have hit a snag. I can't rock the alignment on the BC band. I can set up the initial 1720KHz adjustment just fine. The next step in the sequence is to set the 1500KHz freq but when I do the adjustment; nada. Nothing happens. This procedure is done at the small trimmer cap situated on the main tuning condenser.The tone from the sig gen comes in around 1400KHz. I wonder if any of the Philco Guru have come across this and how did they cure it? All the other alignment steps seem to work okay.<BR>Jesse<P>------------------<BR>If it Ain't Broke; don't fix it!


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 Post subject: Unable to Rock
PostPosted: Feb Wed 11, 2004 6:18 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 531
Location: Austin TX
I took a look at the schematic for your radio. The thing that seemed the best possibility was that the band switch was in the pushbutton position when you were attempting to set compensator 7. In the pushbutton switch position, the section of the tuning cap you were attempting to adjust is out of the circuit. Could that be it?<P>------------------<BR>


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 Post subject: Unable to Rock
PostPosted: Feb Wed 11, 2004 6:32 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 117
Location: Brookeland, Tx USA
Carter, I took that in to consideration also. I double checked the position of the bandswitch and it was on BC. I'll keep digging into the problem.<P>Jesse<P>------------------<BR>If it Ain't Broke; don't fix it!


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 Post subject: Unable to Rock
PostPosted: Feb Wed 11, 2004 7:05 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1391
Location: Fairfield, OH USA
Jesse,<P>I recently aligned a Grunow 5-tube set with a similar problem: The adjustment at 1400kHz seemed to have no effect when the screw was turned. The problem was that the output from the signal generator was much too strong when connected directly (according to the instructions) through a capacitor. I loose-coupled the cable from the generator to the set and then the alignment went as expected.<P>------------------<BR>Vinton Roush<BR>Fairfield, OH


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 Post subject: Unable to Rock
PostPosted: Feb Wed 11, 2004 8:28 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 564
Location: Wisconsin
I had a similar problem with my RCA 224 on the upper shortwave band. I had the oscillator peaked to a harmonic, not the fundamental, so the image was in the wrong place. In that radio, you take the first peak you get when going from full-open on the trimmer towards full-closed.<P>Interestingly enough, the first peak may not be the strongest.<P>Tom<P>------------------<BR>


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 Post subject: Unable to Rock
PostPosted: Feb Sun 15, 2004 7:14 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 117
Location: Brookeland, Tx USA
Problem solved! As Voroush pointed out, I was coupled too tight with the .1 cap. I backed the probe away from the test point and backed the attenuator down and it came in perfectly.<P>Jesse<P>------------------<BR>If it Ain't Broke; don't fix it!


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