[Amps] 4CX5000/10000 Screen power supply help needed

[Radio WC6W]

Hi Hsu,
  You might make a series regulator with one of these FET's controlled by a LM317.  A foldback limiter is mandatory.

http://ixapps.ixys.com/DataSheet/DS100286(IXTH3N150).pdf

  or for a bit more headroom

http://ixapps.ixys.com/DataSheet/DS99761B(IXTH1N250).pdf

  A small (10 mA?) bleed should be sufficient.

  A crowbar with a suitable SCR to protect the tube & socket is nice extra.

http://ixdev.ixys.com/DataSheet/L025.pdf

73 & Happy New Year,
  Marv WC6W

http://qsl.net/wc6w/

> >
> >    ----- Original Message -----
> >    From: Hsu
> >    To: amps at contesting.com
> >    Cc: ham_amplifiers at yahoogroups.com
> >    Sent: Sunday, January 01, 2012 10:43 PM
> >    Subject: [rfamplifiers] 4CX5000/10000
> Screen power supply help needed
> >
> >
> >
> >    Happy newyear to everybody!
> >    I have no experience on building over 2kW
> amplifier.I'll try this project
> >    this year.
> >    I just get a brand new socket and will
> oredr some parts after new year.
> >    I think the regulated screen supply to
> mess with too.
> >    I study DC9DZ 4CX10000D amplifier
> project,
> >    DC9DZ use expensive high power and rare
> zener diode in serial as screen
> >    shunt regulator power supply ,
> >    but I think it is expensive and poor
> dynamic spec and bad IM3.
> >    I think the screen power supply based on
> G3SEK's design is the best, but as
> >    4CX10000D and 4CX5000's sceeen
> >    PS is difficult , too much power and too
> high voltage , even parallel and
> >    serial over 10 MOSFETs. Any suggestion?
> >
> >    73!Hsu
> >
>