Simplex Model PB - I.F. Transformer Alignment | Out of Circuit M&P

A simple M&P to closely align an I.F. Transformer out of circuit.
Build a Simple Circuit to Measure LC Resonant Frequency
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Reference the video description for a link to the schematic.
In addition, check out my earlier video and others where I introduce the Simplex, model PB mini-cathedral dual-band receiver I acquired about nine years back that's been in storage. The seller at the time told me the radio was from a family in the Charleston, SC area; other than that, I don't have any other information on the history of the receiver with the exception of the Simplex factory was located in Philadelphia, PA then later moved to Sandusky, OH where the company was purchased by Philco and the plant was closed shortly after.
The playlist for the Simplex Model PB restoration:
• Simplex Model PB | Res...
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[@tectalabyss]

Hi Don. Sorry for my lack of comments. Your videos have been great and I shared and liked them. All my very best.

[@RestoreOldRadios]

No worries Bobby. I always appreciate you watching, sharing and reaching out. All the best. Don

[@W1RMD]

Nice circuit Don. I just need to save up some money so I can afford that volt meter. I have a NanoVNA H and have used it on my Sickles transformer on a Silvertone 701 I'm trying to get going. Your videos have been a HUGE help in this restoration! The top half of the transformer, I believe is the secondary, has a 330k (330M in 1940 talk) in series with a 47k resistor, then has another wire that bypasses the 330k and only has the 47k in series. These resistors are both INSIDE the can. Should I bypass these to perform the measurements? I noticed that I can't get any response on the nanoVNA on that half of the transformer.

[@RestoreOldRadios]

Ryan - since I don’t have a NanoVNA I can’t say for sure how the resistors impact or influence the resonant frequency. I assume the DC resistance for the primary and secondary coils are good? Best, Don

[@W1RMD]

@@RestoreOldRadios Yes, they both check at 8 ohms. This also has variable capacitors instead of the newer kind with variable inductors so hopefully no "silver mica disease". I'm working on a switched attenuator that goes to 30 dB and will use my NanoVNA as a signal generator and use one of your detector circuits. I don't have any alignment info on this radio, but it's relatively simple compared to older communication receivers like the R-390.