We had something similar at my club with a GU84B tube.
When the tube warmed up, there was a connection between grid and
cathode. It still worked but got very hot. Fault was not evident when
tube was cold. Replaced the tube and problem went away.
Whilst on that subject, does anybody have any theories or suggestions
to clear the fault in the tube. We have a spare socket and heater
transformer and so we have thought of a rubber hammer or discharging
a capacitor through the fault when the tube is hot. We have
nothing to lose as the tube is buggered so all suggestions will be
considered and/or tried.
73, Alek.
VK6APK
At 02:26 AM 8/06/2010, Gary Smith wrote:
>Hello to the group.
>When I switch on the centurion amp, the plate current meter is
>resting at zero.
>Then a click is heard, the plate current meter jumps up to 300 Ma.
>Cannot dip the plate, still have Po tho.
>Any suggestions where to look first?
>73,
>Gary...wa6fgi
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>=======
>Email scanned by PC Tools - No viruses or spyware found.
>(Email Guard: 7.0.0.18, Virus/Spyware Database: 6.15160)
>http://www.pctools.com/
>=======
From sunny Binningup, Western Australia
http://www.qrz.com/db/vk6apk
http://www.qrz.com/db/vk6ap
=======
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.18, Virus/Spyware Database: 6.15160)
http://www.pctools.com/
=======
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|