[AMPS] two questions and a self-contradiction

[w8jitom@postoffice.worldnet.att.net]

> From:          km1h@juno.com (km1h @ juno.com)
> Subject:       Re: [AMPS] two questions
> Date:          Sat, 6 Sep 97 20:34:53 +0000

> tubes Ian. My primary concern is with HV insulation breakdown. A properly
> spec'd  5V 30A  fil xfmr is designed with 5KV or more insulation and will
> not place the HV out on the AC mains in case of a catastrophic tube
> failure, etc.

Hmmmm.

So it's OK to float the grids via some fusible resistance, but you 
still worry about 5 kV on the filament winding?

Maybe if you grounded the grids, the filament wouldn't fly up to 
the positive anode supply rail voltage? The grid would be "in the 
way" of the arc.
 
> Even 811A's at 1500V may be a safety issue. I prefer to err on the safe
> side.

OK ;-)

73, Tom W8JI

--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm