[NJARC] Philco Alignment question 40-150

[Jim Whartenby]

Joe
I'm no Philco expert but will try to help.

I'll assume that you have checked all resistors to see if they are
within their tolerance.  Capacitors are a bit harder to check without a
cap analyzer.  I usually just replace all paper caps to save on
troubleshooting time.  I'm not a purist, I just want the set to work
better then new.

If you have replaced components, check against the schematic to be sure
that all components are connected to the proper terminals.  It is too
easy to miswire components, especially in a crowded chassis.  One
caution to mention is that the set wiring may not follow the schematic
exactly since most manufacturers modify the radio over several
production runs.

If your schematic has voltage measurements, check to see if your set is
close.  Expect to see higher readings then given since you most likely
are using a DVM with very high ohms per volt.  That is to say the DVM
is not loading down the circuit.  Your DVM is battery powered and
doesn't need to take any power from the circuit to get a reading.

Check all coils to be sure that they are not open.  If one IF
transformer tunes properly and the other is broad and insensitive,
check for an open L or C.  I had an open cap in a Philco IFT not too
long ago.

One last thing.  "M" was the shorthand multiplier for 1000 not
1,000,000.
Regards,
Jim

--- TrainBee at aol.com wrote:

> Visit our web site - See http://www.njarc.org
> _______________________________________________
> Dear Philco experts,
>     I am having a difficult time aligning my Philco 40-150.  I can
> get the IF 
> at 455 and the SW at 18 MC.  After that the trouble starts. I believe
> that I 
> am setting everything OK per the instructions.  I've identified the
> oscillator 
> and antenna adjustments and adjust them per the instructions.  After
> I do all 
> of this, I end up with the AM band receiving off frequency and a howl
> in the 
> lower half of the band.  
>     Have any of you worked on one of these before and what did you do
> to get 
> it to play?  For a reference, this is one of the Philco's with the
> slant 
> front.  
>     There is a chance that I am setting the IF coils in the wrong
> order.  Is 
> there an order to follow?  I can't tell from the instructions.  
>     I am using a Heathkit signal generator to align the radio.
> 
> Thanks for any help.
> Joe Devonshire
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