No more 455Khz IF transformers ? Is analog Superhet obsolete..

I went looking for specs & sources of those IFT cans which were used in superhet receivers, and found almost nothing.

Has everything gone digital ? Or am I looking in the wrong places ?

My application is somewhat different. It is to implement a double-tuned BPF, with voltage gain as well.

What I need is a small (signal) transformer with a high-ish ratio of around 1:30 or more if possible. It would work in the region of 100Khz to 400Khz. The larger coil would be in the region of around 0.5mH. And it needs to be tuneable !

And lastly - as stable as feasible/ practical. Less than 200ppm/ deg C?

Yes they are pretty much obsolete unless you need mass production qty.

Everything has pretty much gone to ceramic resonators
455Khz with 150 pc min order here
http://uk.farnell.com/murata/cfwla45...khz/dp/1401177

Well they are still available on eBay as hobbyist items. Some even sold as complete set for making a superhet radio (Red = OSC, Yellow=1st IF, White=2nd IF, Black=3rd IF).
http://www.ebay.com/sch/i.html?_from...ormer&_sacat=0

I still have a few 6-transistors AM/FM radios where there are some of these IFT to be used as parts. No sure if the cheap Chinese multi-band radios use IFT or ceramic resonators.

Allen

there are a few superhet receiver chips that still work with a 10.7 MHz if. switch to that frequency plan.

Thanks, but I am not looking to build a radio. It's for a different application.



Any pointers on who could make such a trafo, if the mass qty requirement was there ?

Xicon still produce through-hole IF transformers for 455kHz and 10.7MHz:

455kHz
http://www2.mouser.com/ProductDetail...%2fg4WPFuwk%3d

10.7MHz
http://www2.mouser.com/ProductDetail...ip%2fJwIFxw%3d

Through-hole ceramic resonators (various frequencies) are still available from many vendors and manufacturers.