-----Original Message-----
From: Phil Clements <philk5pc@tyler.net>
To: Rich Measures <measures@vcnet.com>
To: <amps@contesting.com>
Date: Wednesday, August 11, 1999 9:45 PM
Subject: Re: [AMPS] Re:(AMPS) sb-200 troubles
>
>
>? A 5kV Load-C clearly belongs in a tetrode with handles amplifier.
>
>
>I always over-engineer in hope that Santa will bring me a suitable tube!
>
>? I have never seen a leaky C-block. When barium titanate dielectric
>starts to breakdown, a short is virtually certain within mS.
>
>
>I have seen some weird things on c-blocks that use several door knobs
>in parallel. Most of my door knob failues have failed open, so far. The
>ceramic fails, and the two metal ends mechanically part company
>with it.
>
>>The safety RF choke in my amps does two things; it protects
>>more expensive components from carbon build-up an damage,
>>and it keeps me from being published in QST in the "Silent Keys"
>>column!
>>
>? For the Silent Keys scenario to take place, C-block would have to
>short, the amplifier would have to be in TX mode, and C2 would have to be
>clearly overinsulated -- and then the operator would have to grab the
>ungrounded side of the antenna. .
>
>Murphy's 45th Law states that some T-R relays are less robust that C2's;
>(BTW; there is always HV on one side of my C-block, even when receiving.)
>The "Silent Key" event would take place if my XYL's favorite dog was using
>my ground-mounted vertical for a fire plug at the moment the event took place!
>Remember Murphy! I just confirmed Murphy's 14th law this morning.... I dropped
>my toast on the floor, and the buttered side was on the bottom, just as the
>law had predicted!
>
>Later, Rich
>
>Phil
>
>
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|