Published On Apr 26, 2020
Last year I had a radio to repair that had a destroyed 2nd stage IF transformer; it was not repairable. Rather than scrap the radio I decided to research how hard it would be to engineer and build a modern replacement. Having no coil winder I had to use off the shelf parts. I found some existing work online and used it for the basis of the design that I present in this video
In this first video, I will go through the process of building a new IF transformer, pre-tuning it and installing it into the radio. The design uses PCB assemblies that I designed and had made at a local PCB fab house.
In the second part of this mini-series I will go through the design process of this part, review the original source ideas and go through parts selection.
For those who want to try this before the next video is ready, here are the part values that I use in this video:
Inductor/Choke : 1200 uH 17.5 ohm (Digikey: 495-76031-1-ND)
Bulk Caps : 56 pF NP0/C0G (Though-hole PN# Digikey: 399-9743-ND)
Trimmer Cap : 8-40 pF (Digikey: 1674-1014-1-ND)