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All, I need lots of advice on numerous fronts. I’ve got several threads going on the radio, one is showing off the cabinet in the antique radio discussion forum Zephyr , another is asking whether I can plug it in without the speaker http://philcoradio.com/phorum/showthread.php?tid=11244 and the third is on the antenna http://philcoradio.com/phorum/showthread.php?tid=10884 . Now I’m moving onto what I hope is my last problem and since it’s on a different topic I thought I’d start a new thread. The radio is a Philco 40-165 installed in a Zephyr Radiobar cabinet. Based on capacitors of various vintages I suspect I’m working on the third rebuild. So far I have replaced all of the paper and electrolytic capacitors and all of the out of spec resistors. Much but not all of the rubber wiring has been replaced. When I power it up I could hear a loud ticking noise through the speaker. While trying to locate this noise I noticed that the previous repairman had opened up the second IF transformer based on the observation that it was loose and was missing the nut at the top of the can. By adjusting the mica capacitors on this transformer I was able to get the ticking noise to go away but now I need to align this set. The manual says to use an alignment socket adapter. I suspect I don’t need this if I attach my VTVM to the correct pins under the chassis but I have no idea what pins to use. So my question is how to connect my VTVM when I don’t have the alignment adapter?
I told all my friends that I’d have this project finished by the end of the year and I only have 14 hours left.
Thanks in advance,
Keith
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Someone else should check me on this but the full service bulletin #326 that you can find here (you need the djvu reader to see it) says the output meter should measure the AC voltage across the screen grid and plate of the 41 output tube. That would be pins 2 & 3. Those pins drive the primary of the output transformer so you could also connect to a point where the black and white wires of the transformer connect if its not at the tube pins (if there is an spot to do so...I've not worked on one of these). I believe the adapter just allows you to put the tube in place and access pins 2&3 from on top of the set.
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(12-31-2014, 11:47 AM)keith49vj3 Wrote: All, I need lots of advice on numerous fronts. I’ve got several threads going on the radio, one is showing off the cabinet in the antique radio discussion forum Zephyr , another is asking whether I can plug it in without the speaker http://philcoradio.com/phorum/showthread.php?tid=11244 and the third is on the antenna http://philcoradio.com/phorum/showthread.php?tid=10884 . Now I’m moving onto what I hope is my last problem and since it’s on a different topic I thought I’d start a new thread. The radio is a Philco 40-165 installed in a Zephyr Radiobar cabinet. Based on capacitors of various vintages I suspect I’m working on the third rebuild. So far I have replaced all of the paper and electrolytic capacitors and all of the out of spec resistors. Much but not all of the rubber wiring has been replaced. When I power it up I could hear a loud ticking noise through the speaker. While trying to locate this noise I noticed that the previous repairman had opened up the second IF transformer based on the observation that it was loose and was missing the nut at the top of the can. By adjusting the mica capacitors on this transformer I was able to get the ticking noise to go away but now I need to align this set. The manual says to use an alignment socket adapter. I suspect I don’t need this if I attach my VTVM to the correct pins under the chassis but I have no idea what pins to use. So my question is how to connect my VTVM when I don’t have the alignment adapter?
I told all my friends that I’d have this project finished by the end of the year and I only have 14 hours left.
Thanks in advance,
Keith
I a pretty much always align via AVC on all my radios, including my 40-180 which also called for a tube adaptor. I believe on your radio that would be the intersection of R6, C7, R38, and the 1st IF. But I'm not 100% sure on that.
Either way, I believe that adaptor just taps pin 6 of the tube it's inserted to. So maybe my guess above about the AVC is off slightly.
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I'm embarrassed to admit I'm not sure what an "audio output meter" is, Is this the same as an AC volt meter?
Keith
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No worries. Yep basically an AC volt meter that probably has a capacitor on the front end to block and DC. Here's a picture of one in another post.
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Well I hooked up one of my AC voltmeters between pins 2 and 3 of the 41 tube and I do get a deflection that gets bigger as the tone get louder. I could easily solder a couple of leads between these two pins to run to my AC voltmeter and then I could do the alignment in the cabinet. Any reason not to do it this way?
Thanks,
Keith
(This post was last modified: 12-31-2014, 05:12 PM by keith49vj3.)
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I don't think there should be any reason you could not do that. I've had sets that had a terminal strip with lugs on the top of the chassis that you connect to for alignment while the set is in the cabinet. Just be sure they don't short to something when disconnected.
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I've probably only done a half dozen or so alignments so my experience is minimal but I think something is wrong. The first alignment step is to inject a 455kH signal into the #1 antenna post and adjust the IF cans. I'm doing this one on my bench since i don't think I need the antenna's attached for step one. As I peak the IF cans I can hear the signal generator through my speaker get louder while the voltage goes up on my output meter. However, if I go too far the frequency coming out of the speaker drops while the voltage on the output meter is still increasing. So, if I peak the IF cans based on the meter and the proper frequency coming out of the speaker everything is fine but when I unplug the generator I get a loud low frequency buzzing noise coming out of the speaker. I'm wondering if the previous repairman found something wrong with this radio and gave up. When i got this radio only about half of the caps had been replaced and the IF cans were loose in the chassis and one had the nut missing on the top of the can. Could it be that I need to do all the alignment steps with the antenna's attached or am I looking at a bigger problem?
Thanks and Happy New Year.
Keith
(This post was last modified: 01-01-2015, 07:25 AM by keith49vj3.)
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Well, I still use the secondary (voice coil) winding and an old analog VTVM to display AC volts resulting from the modulated IF frequency injected into the set as I peak the IF coils from last to first stage in that order. If the noise bothers you, you can sub a 4 ohm resistor for the speaker whilst aligning. My signal generator is a senior citizen too, so I let it warm up for a half hour, and check the output with modern digital frequency counter (which can be had for a pittance.) That way I have an accurate signal to start with, and not much else to muddy the waters.
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This is getting interesting. I found the nut that attaches the compression capacitors to the stud on the top of the first IF can to be loose. So I tightened it up and re-assembled the can. I then attempted a new alignment but the 455kH tone sounded horrible (wobbly) so I decided to give up. When my hand touched the #1 antenna terminal when I was disconnecting my signal generator the radio started to play and I can get most stations using me as an antenna. The radio sounds pretty good too. So now I've got to get this in the cabinet and try the alignment once again. Just to make things clear I wasn't drinking last night.
Keith
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I put the radio into the cabinet hooked up the antenna's and it sounds great. I can turn the screws in and out on the IF cans and the radio still sounds great.
Confused
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Well Keith I was hoping one of the guys that's better at the electronics than me would jump in like codefox did. I'm in the camp of 'if it ain't broke, don't fix it'. 
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In order to achieve an accurate and thorough alignment on a Philco set which uses a built-in loop antenna, it is required that the loop be connected during the alignment procedure.
--
Ron Ramirez
Ferdinand IN
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Thanks everyone, I finally ended up getting the set aligned. It turns out that I had a bad connector on my Eico Signal generator that was complicating matters. The radio plays pretty well and by un-soldering one wire on the volume control I was able to add a connection for an MP3 adapter. I used this design for my MP3 adapter http://www.antiqueradios.com/forums/view...f6f0b5d4e6 I just ordered a bluetooth receiver so I should be able to play the radio using bluetooth from my phone.
Keith
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I like a happy ending. Best!
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