The protective choke opens when the HV is applied to it,
preventing HV to go all the way to your antenna.
It is caused by one of two things....leaking/shorted plate block
capacitors, or some critter or conductive object shorted the
plate block cap out momentarily.
I would change out the plate block cap(s) while you have the thing opened up.
(((73)))
Phil, K5PC
----- Original Message -----
From: Jim <jdc@ieway.com>
To: Jim <jdc@ieway.com>; <amps@contesting.com>
Sent: Thursday, November 25, 1999 11:50 AM
Subject: Re: [AMPS] Band Switch arcing SB-1000/AL-80
>
> Well...........Looks like the amp is fixed....When I first started, the 2.5
> Mh choke that is across the output of the tank (prevents high voltage from
> appearing on antenna if the DC blocking caps shorts), was burned open. I
> replaced it with a 220K 2 watt resistor. (A trick I had learned from Rich
> Measures). I installed a 2.4 Mh choke and the arcing stopped completely.
>
> Even removed all of the nicrome wire suppressers.
>
> What would cause the choke to open. ?
>
> Thanks and Happy Thanksgiving to all!!!
>
>
> Jim W7RY
>
>
> -----Original Message-----
> From: Jim <jdc@ieway.com>
> To: amps@contesting.com <amps@contesting.com>
To: <amps@contesting.com>
> Date: Wednesday, November 24, 1999 6:04 AM
> Subject: [AMPS] Band Switch arcing SB-1000/AL-80
>
>
> >
> >I know there was a thread about this a bit ago........But.......
> >
> >
> >The arcing that I am having is in the front wafer of the switch. This
> wafer
> >just switches the tuning cap padder for 160 meters. The
> >cap is 170 Pf. The open contacts arc when in the 80 meter position. I am
> >not sure if it is a parasitic or not. I would say not.
> >
> >Riches special plate suppresser is installed in the plate lead. The gap
> >that arcs is almost 3/4 inches wide! Why does the tune cap itself arc ?
> >
> >Did Ameritron re-design this portion of the switch ?
> >
> >I really do not want to replace an $ 80.00 switch. Let alone the fuss of
> >replacing it.
> >
> >73 to all and happy Thanksgiving....
> >
> >Jim W7RY
> >
> >
> >
> >
> >--
> >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
> >
> >
>
>
> --
> 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
>
--
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