Rod Pentode TRF

[BusyBee]

I have found great differences as previously reported and the results do indicate that individual setting up may well be beneficial. My samples were 1j24b's. I do wonder whether 1j24b-v's would have closer characteristics but I do not have any to compare.

I think there is only one grade of 1j24b. The 1j29 series and 1p24 series both come in different grades, but the differences may be mechanical or power handling rather than electrical uniformity.

Thanks for this. Now I am reminded I do think you may have mentioned it before but I had forgotten. It does make me wonder all the more about how the Russians handled such variation.