[Amps] Gonset GSB-201 Mods

[KA9S - 2]

The paragraph above that stated:

"I am getting a Gonset GSB-201 that has modifications. ........... it now
has 4 - 572B tubes in it,
the HV power supply filter capacitors have been replaced with modern ones
(on a
circuit board), and the HV choke input filter choke is missing"

2100 volts is not too high for the 572B tubes. I can't resonate a missing
choke. I only operate CW.


The Questions:

Can the power transformer handle the instantaneous peak current demanded by
a
capacitor input filter? Can the final tank circuit components handle the
increased peak RF voltage and current? (Blocking cap, plate tuning cap, HV
DC
RF choke). Has anyone done this successfully?

73s - Jeff - KA9S

----- Original Message ----- 
From: <R>; "Measures" <r at somis.org>
To: "Jim Tonne" <tonne at comcast.net>
Cc: "KA9S - 2" <ka9s2 at comcast.net>; "AMPs" <amps at contesting.com>
Sent: Thursday, March 23, 2006 11:17 AM
Subject: Re: [Amps] Gonset GSB-201 Mods


> 2100v is too much for 811As. The HV PS power supply's regulation can be
> improved for SSB by resonating the filter choke at 120Hz with a cap.
> However, for AM there is no benefit.
>
> Another improvement is to remove the RCA "neutralization" circuitry
> since it is know to cause VHF surprises.
>
> On Mar 23, 2006, at 9:04 AM, Jim Tonne wrote:
>
> >
> > If that 50k resistor is the bleeder on the power supply,
> > * leave it alone *  !!!
> >
> >>  I had been thinking that changing the HV supply from
> >> choke input to capacitor input would boost the HV up
> >> to 2100 V and eliminate the need for the 50k 100W
> >> load resistor (it adds 45W of extra heat).
> >
> > - Jim WB6BLD
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps at contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> >
>
>
>
> Rich Measures, 805.386.3734, AG6K, www.somis.org
>