[Amps] Russian tubes

[WA2BPE]

Gentlemen:

Two questions, please:

1.  Can anyone clarify the "lifetime" spec given on the Russian tube
data sheets.  It just seems that 500-1000 hours, etc., is low compared
to US tube specs.  Perhaps there is some unwritten criteria that I have
missed.

2.  What experience have folks had using these tubes, especially in the
144, 222, 432 MHz bands?  I have seen some sites with schematics & pics,
but not many experience dissertations (good & bad).

Thanks & 73,

Tom - WA2BPE