Re: [TenTec] another amp question

["CCW" <walkercc@earthlink.net>]

I once had an amplifier that exploded, blew up with a huge report and 
fireball , and blew me through a window in my shack.
The fire department said that they had never seen such an explosion.

Amplifiers can blow up, and when they do, hold on to your CB gear!

K4NTY
----- Original Message ----- 
From: "Gary Hoffman" <ghoffman@spacetech.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Thursday, April 03, 2008 6:57 PM
Subject: Re: [TenTec] another amp question


> To me this whole parasitic issue is very nerve wracking.
>
> This issue seems to be that absolutely no one can say what triggers it 
> with
> certainty, nor do people agree on the fix.  Obviously ham radio
> manufacturers build amps that they feel are appropriate and well behaved.
> They work for years.  Then Blam !
>
> Some people claim it is not even real - they just say that component
> failures happen, and trigger noisy failure modes.
>
> But there is a very credible body of evidence to the contrary also.
>
> There are many folks advocating relatively advanced modifications...and
> another group who claim these are not worth the paper upon which they are
> written.
>
> I'm not convinced pro or con....but I have blown up two amplifiers, not 
> due
> to operator error either.
>
> I guess I better just sign off on the subject yet again, since I'm not
> really able to contribute much and no one has yet convinced me with
> certainty that they have THE answer either.
>
> 73 de Gary, AA2IZ
>
>
> ----- Original Message ----- 
> From: "jerome schatten" <romers@shaw.ca>
> To: <tentec@contesting.com>
> Sent: Thursday, April 03, 2008 6:28 PM
> Subject: [TenTec] another amp question
>
>
> > Learned gentlemen...
> >
> > Excuse me if this is somewhat off-topic, but I've been following the
> > 811 amp discussion with much interest and have a related question:
> >
> > I'm currently doing some work my pair of 813's and was thinking about
> > the 'parasitic' problem as discussed on this list.
> >
> > My fear is not blowing the tubes or the band switch, but rather in
> > blowing the front end of a modern transceiver driving it.  The
> > configuration is a pair of 813's truly running zero bias GG (grids all
> > tied together and connected directly to ground ~ 50 ma. idle current
> > at 2200v). No band switch (rotary inductor pi-network). Manual
> > switching tx/rx avoids hot switching. Input to the amp is grounded in
> > Rx. Works 80 thru 20 only.
> >
> > Should I be worried about the parasitic problem taking out what's
> > driving it?  If so, how to prevent (minimize) that?  In the 40 years
> > I've been running this beast (still the same set of tubes) I've driven
> > it with everything from a Viking Ranger, to a Jupiter and never had so
> > much as burp. But one never knows.
> >
> > Getting nervous in Vancouver,
> > va7vv
> > --
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