Hieveryone!
MyEmtron DX-1b with QSK-option (vacuum-relay), bought new in 2002, hasbeen
working flawlessly with the original GU74b until some weeks ago.Never used with
more than 700w out.
Todayssituation: When using the amp intensly, as within a contest, aftersome
minutes, the protection system cuts off for some seconds, as forexample in case
of hight SWR. However, this cut-off occursindependently of driving transceiver,
power, antenna, SWR andtemperature. The LED-indicators for IG2 start quickly to
rise, jumpover to «overdrive» and cut-off happens. After 2 sec. amp is
readyagain, everything seems to be normal, but the symptoms repeatthemselves.
Ihave adjusted tx-delay in trcv with bk, semi-bk, full-bk andtransmit-receive
button, keying by MOS or reed relay; no difference.
HVshows normal value at the meter: 2.6 kV
Isuspected the tube, so 2 weeks ago the original tube has beenreplaced with a
(formatted) spare one, no difference. IG-voltage isexactly as required 356 V.
Trcvris a IC7610. It drives other amps (Expert 1K-FA, AL-572) withoutproblems.
Iwould be grateful for any hints.
73sfrom Norway
Uli,LA0CX
--
Sikkert sent med Tutanota. Krev din kryptert postkassen i dag!
https://tutanota.com
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|