|
Title: Eimac 250T Post by: W8ACR on December 03, 2019, 09:34:51 PM I recently acquired an Eimac 250T - NOT a 250TH or 250TL. The designation on the glass envelope is 250T.
There are some additional characters inside the envelope down low where the filament leads come up from the base. "0-209-HI" I assume this tube is the equivalent of the 250TH. I think that the earlier versions of the T series tubes were marked either "HI" or "LO" inside the envelope. Later versions were marked TH or TL on the outside of the envelope. Is this correct? Thanks, Ron Title: Re: Eimac 250T Post by: ae7db on December 04, 2019, 04:07:42 PM Your supposition sounds likely to be correct. Attached is an Eimac data sheet that specifically says the "LO" is marked on the filament stem for a 250TL, so it seems reasonable that if yours is marked 'HI" it is an early 250TH. AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
Dean |