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new guy again,, 44 chassis - Printable Version

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RE: new guy again,, 44 chassis - Nathan Slingerland - 04-27-2018

Bob - I don't see Model 44 instructions among our downloadable files. Is that your scan?

RE: new guy again,, 44 chassis - klondike98 - 04-28-2018

Nathan, check your email.

RE: new guy again,, 44 chassis - Nathan Slingerland - 04-28-2018

Done. Icon_thumbup

RE: new guy again,, 44 chassis - safeshow - 05-02-2018

I am still going on with this, I did get one spanish station (not real clear)
3 questions
1. anyone know what band is FM? (the dial knob has 4 spots just wondering which on is FM)
2. I am gonna start checking the coils in more detail do you guys just ohm them?
3. Is there some type of RF signal generator you use to insert a rf signal for troubleshooting?

thanks all this piece is beating me up

RE: new guy again,, 44 chassis - klondike98 - 05-02-2018

The 44 does not have FM. FM as we know it today did not start until post WWII. There was some FM in the early 1940s but on a different frequency range than today's stations. Your set has 4 bands. Three shortwave bands (that range from 1.5 to 23 megahertz and one broadcast (known today as AM) band. The schematic info has the ranges for each of the bands. The AM band is selected by turning the wave-band switch fully counter clockwise. (see the instructions)

Yes you can check the coils by just checking their resistance. Usually something in the range of 10 to 30 ohms. The schematic has the values on it.

Alignment is done with a signal generator that supplies an RF signal with an audio frequency modulating it (usually about 400 Hz). An example (I'm not suggesting you buy this one) that is currently on ebay is seen at this LINK.

RE: new guy again,, 44 chassis - Electrothaumaturgist - 05-03-2018

As a slight addendum to the FM discussion, the 1942 Philco 42-400 that I restored a few years ago had the old-style FM circuit. I was able to attune the circuit to receive the full range of the modern frequencies, apparently compressing the signal to fit into the spectrum, then spreading it over the bandwidth, so it actually tracked quite nicely up and down the scale and received all the stations as far as I could tell- as many as my modern FM test radio I had there. The FM scale wasn't so precisely marked upon the dialface, so it was close enough, and the FM sounded marvelous! I think Ron attributed that PHenomenon to some kind of oblique harmonic resonance signal that it was picking up. However the method, it worked! I guess when you spend about 100 hours or so aligning it up by ear, you're bound to stumble upon a big surprise. Or was it just lady luck there smiling? It was almost surreal hearing grunge rock blasting out of that beautiful console!   Icon_cool

RE: new guy again,, 44 chassis - safeshow - 05-03-2018

Sorry guys I meant which position is AM not FM

RE: new guy again,, 44 chassis - safeshow - 05-04-2018

Ok I replaced all of the caps and the resistors still had the same, then I adjusted the 1ST AND 2ND I.F coil adjustments and I got AM 1060 (our local strong station to come in )

My question is this piece has
3 adjustments on the back (wave trap and 2 compensating condensers)
2 I.F coil adjustments (on top of the coils)
2 Osc. adjustments (on top of the tuner)
Anyone have any thoughts on these adjustments? and how if at all to adjust them without a boat load of equipment?
thanks all !!

RE: new guy again,, 44 chassis - klondike98 - 05-04-2018

Mike, he mentioned that he meant AM instead of FM a couple posts back. He was also asking about a signal generator so I think the answer is "no" to full alignment.

RE: new guy again,, 44 chassis - morzh - 05-04-2018

Ok then. The questions are withdrawn. Still needs the alignment.
If there's no generator there's no good sub for it. But if it is anywhere near the required frequencies (read - receives some stations in the general vicinity of where it should be) and a strong local station is present, it could be used as a sub.

New guy chassis 44 - safeshow - 05-05-2018

Thought id start a new thresd [the new thread was merged with the original thread to keep the discussion together..Moderator]
question I have is Does anyone know or can explain the 3 Adjustments on the back?

3 adjustments on the back (wave trap and 2 compensating condensers)  
I would think they would be for the end user to adjust(do to there location)

RE: New guy chassis 44 - morzh - 05-05-2018

29 and 30 are 1st IF alignment.
3 is IF trap and can be disregarded.
in fact it all is shown on page 2 in Figure 2, which also has all other alignments explained.

RE: new guy again,, 44 chassis - klondike98 - 05-05-2018

I merged your new thread with the original 44 chassis thread to keep the discussion together per the Phorum Rules.  

As morzh notes, those adjustments on the back are used to align the set and are described in the schematic information found on nostalgiaair.  They were not meant for the home user to adjust since they require some knowledge about the alignment procedure.  I have never done an alignment on a 44 but generally it is done with a signal generator mentioned in an earlier post with adjustments to the various IF transformers and the oscillator in a particular order with the correct signal generator settings while monitoring the output voltage across the output transformer primary.

Here's a summary alignment chart taken from John Riders "Aligning Philco Receivers" from 1937, p. 66.

[Image: https://www.dropbox.com/s/wr9z55mx92s7k17/44-alignment.jpg?raw=1]