WAAY-TV ran a Varian 4KM150LA for over 200,000 hours @ 55KW out. It
was the longest lasting Varian Klystron in 1992 ( written up in
Broadcast Engineering )and lasted another 17 years. Over a quarter
million hours.
Don WA4NPL
Quoting "Ron Youvan" <ka4inm@tampabay.rr.com>:
> < There is a broadcast station that has kept a set of finals in stand bye,
> running at mildly reduced filament voltage, not dark heat, for
> something like
> 30,000 or 40,000 hours... Had the tubes tested and they still met new specs..
> Last thing I read the tubes are pushing 70,000 hours... Perhaps
> someone in the
> group with a better memory, or better sources, can elaborate...
>>
>
> I ran EEV/E2V K3672-BCD 65 kW klystrons past 100,000 hours,
> operating them 24/7 except for 5
> hours Monday morning, but I used "black heat" when beam Voltage was
> not present.
> (this dropped the filament Voltage from 8/8.5 Volts to 6.0 Volts)
> This 240,000 Watt transmitter
> operated at only 200,000 Watts, 55 kW from each tube instead of 65 kW)
> Someplace past 105/6,000 hours the tubes "fall apart," so we
> replaced them just after 100,000 hours.
> --
> Ron KA4INM - The only real problem is death is so final.
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|