RCA 21CT55 #8802897 is Dead

[dtvmcdonald]

Originally Posted by Electronic M

I just use the peaking coils off digikey that Nick Miniman82 recommended many years ago. Such as this (this is one of several from that list): https://www.digikey.com/en/products/...-223-rc/969835
.

Those or the API Delavan (Spelling?) look-alikes were what I ended up with
in all cases. Only one, the 6.8 mH one in the Q, needed a value much different than the spec. I also found them to be the best ones in my HF radio 7 to 11 pole bandpass filters.

[Electronic M]

Originally Posted by dtvmcdonald

Those or the API Delavan (Spelling?) look-alikes were what I ended up with
in all cases. Only one, the 6.8 mH one in the Q, needed a value much different than the spec. I also found them to be the best ones in my HF radio 7 to 11 pole bandpass filters.

Interesting. Is there any significant difference between the API made ones that makes them better in some circuits or is it the same either way? Do you remember what value or part you used for the 6.8mH Q coil?