Philco 39-31 Code: 121 - Printable Version

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Philco 39-31 Code: 121 - Sampler1 - 03-24-2020

Hi,
I pulled out the Philco 39-31 code 121 to finally take a shot at doing the alignment. I am a beginner when it comes to vintage radio alignment so please be patient with me.
On step #1  it says to connect  through a .1uf to the grid of 6A8G at a freq. of 470 kc (radio on 580 KC). I am assuming that is pin 5 ? or should I attach to the cap of the tube?
On step 3 it says to attach through a 100 mmf 1550 KC (Radio on 1550 KC) and adjust  # 5 and # 4A . (4A is the trimmer capacitor on the tuning capacitor.) When I try to adjust #4A absolutely nothing happens. ???????

Any help is greatly appreciated.

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RE: Philco 39-31 Code: 121 - mikethedruid - 03-24-2020

First of all, use this data sheet.   https://philcoradio.com/library/download/service%20info/yearbooks/1939/split/Part23-Philco%201939%20RMS%20Year%20Book.pdf     which can be found in the library of this site. If you look at the table about the alignment, you will notice the first column says where to input the signal, to the grid of the 6A8G, meaning the CONTROL grid, i.e. the grid cap, through a .1 mfd condenser, with the wire to the cap removed for aligning the IF frequency. The other signals for aligning the RF frequencies are injected through the antenna connection through a 100 mmfd condenser.

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RE: Philco 39-31 Code: 121 - Sampler1 - 03-25-2020

Much appreciated mikethedruid

Stay well.

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