[Boatanchors] HV fusing in amplifiers

[GEORGE MORTON]

Gents - Fusing HV line is quite simple!  5 ohm 5 watt
resistor (flameproof variety) in series with HV line right off top of the
choke will blow under excess current load before costly tubes will expire.
Brgds to all, Geo

    From: "Rbethman" <rbethman at comcast.net>
To: <Boatanchors at mailman.qth.net>
Sent: Wednesday, May 04, 2005 4:58 PM
Subject: [Boatanchors] HV fusing in amplifiers


> Group,
>
> Has anyone thought about high voltage fusing in an amplifier or "old" BA?
>
> Usually there is a choke in the RF output leg to ground, in the event that
the plate blocking cap fails.
>
> Yes, we usually have power supply fuses or circuit breakers.  BUT - what
will get fried?  How do you protect all that?
>
> I've got ONE HV fuse by GE.  Its design voltage is 2400V.  It is rated at
7A, which is obviously a ridiculous value.  HOWEVER, even IF it was a
reasonable current rating, it is HUGE!  It is 11" long and 2" in dia.
>
> Where in the world would you even mount it?
> -- 
> Bob - NØDGN
>                        Bob Bethman - NØDGN
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