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Well, I have the chassis back together, having torn it down again to check the wafer switches. When I did, I remembered I had changed the leads. As mentioned in the other posting, the resistance was almost three times the desired amount. I replaced them again with a donor set, and they were almost spot on for resistance. I also ohmed out the other BC band coils, and they were fine.
So, I went through and attempted to adjust it. Everything seemed to go well, and now I have SW 1 & 2. I also have the upper third of the BC band, but below 900 it is still squawky, squealy, and burring. I have tried everything I can think of... Any more ideas? Should I just keep attempting to adjust stuff, or is there a potentially specific cause I can start to look for, now we know things are going through that far...
Ideas? Comments?
Thanks!
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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City: Minneapolis/St. Paul MN
I think you need to start over aligning it. At least it squeals and howls at the low end and you get something worthwhile on the high end, that (to me) is a good thing, and it means you're on the right track.
Not having the instructions in front of me, and the alignment I did was about 6 years ago, I'm a little foggy on the details, but I think we can all smell sucess coming! 
Don't give up!
Bill
Sent from my Pentium II on the AT&T Dial Network
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Another concept which has just developed- When I did all the rewiring, I replaced the wires to the two RF cans.(The coils themselves are as original) Originally they were 20 or 22 ga solid, I replaced them with 20ga. stranded. Is it possible I increased the resistance there just enough to scramble up the lower(900 + below) BC bands, while still allowing 900 + up to pass through? Resistance issues seem to be the biggest issue I have been encountering with this radio.
Comments? Answers? Theories? Recipies?
Thanks!
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
Posts: 236
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Joined: Sep 2005
City: Minneapolis/St. Paul MN
If all you did was replace the lead wiring to the coils, IMHO, that shouldn't make a major difference - if it's only a few inches we're talking here that ought to be insignificant. Anyone who knows more on this topic than me (which is probably many of you  ), feel free to chime in.
If the original coils are intact and you have continuity, it should be fine. I think what probably counts more are the number of turns in the coil than actual resistance itself (again, correct me if I've mis-typed), which would throw off the resonant frequency if the wrong number of turns were on the coil.
Bill
Sent from my Pentium II on the AT&T Dial Network
Posts: 1,703
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City: Evanston, IL
In any coil, the winding the D.C. resistance is a minor point. Three factors which greatly effect the inductance value of a re-wound coil is:
Number of turns; Wire gauge; Turns spacing, assuming or course the original form is used.
In a frequency determining winding these are critical to match the original exactly.
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So, since I modified none of these, other than the wire in to the coil, where should I stand? I'd imagine I should be ok, but seeking other answers to this problem?
Thanks!
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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City: Evanston, IL
Maybe lead dress is causing your feedback. Did you route the new wires exactly in the same place as the old?
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Pretty much- I tried to match as closely as I could. I was thinking about that earlier. I just had a look inside, noticed one wire I hadn't replaced: so I replaced it. No change. I also touched up a couple soldered joints, and cleaned the adj. caps with cleaner, and let it dry.
It seems almost as if the dial were "compressed", and below 900 gone, above ranging. Any adjustments throw the others off.(Both SW are working nicely) If I tune 950 in(by turning to position, then dragging it in by turning VC) , then 1210 goes off to one side. If I tune 1060 in, 950 goes off... I have been trying to adjust the BC band "by ear" at this point, having not had luck with the right way. I even tweaked the RF cans, but still get this weird symptom.
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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City: Warren, Ohio
Is the IF frequency accurate? Seems like if this was wrong it would affect SW too.......Something to check anyway.
Steve Chambers
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I had the IF freq all set up as directed. I just started "tweaking" to see if it helps the AM- it doesn't seem to affect the SW bands, though it does seem to improve the BC(although I haven't taken it far from its "correct" setting.) It seems like one or two of the VCs in the IF cans(RF cans, I keep calling them) are pretty tight- but that's where they make the radio happy...
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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City: Evanston, IL
If you used your signal generator to setup the IF, then you should also use it to align the AM band, per the Philco instructions.
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That's how I set it up, and have been working with it, but still having the problem with BC. Of course, I am awaiting delivery of my new toy- A Philco 088 Signal Generator and the matching multimeter, in a Philco wooden box! If I am still futzing with it then, I will attempt to use that for set up...
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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Joined: Dec 2005
I'm definitely not an expert on this, but I was under the impression that you shouldn't change from solid to stranded wire in the RF section of the circuit. RF signals travel along the outside surface of the wire, therefore changing to stranded wire could affect the RF characteristics.
Derek
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I've been wondering about that, but others have told me it makes no difference.. The SW and upper BC bands seem ok(except BC as noted) but lower BC is just screwy, and I am having an awful time with adjusting BC.
Can anyone confirm this? I can swap back to solid wire for those sections if necessary...
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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