[Amps] re: Arcos & Unknown 2m 2x4cx250b designs

[Ian White, G3SEK]

SM3MXR wrote:
>
>  Hi all
>  I have a half built 2m  2x4cx250 project on the bench.
>  It is a strip line type, like the ARCOS 2x4cx250 amplifier I've been
>  using
>  for many years, with some differences.
>  It is built many years ago (>20?) by a local ham, but he remember 
>almost  nothing about it.
>  Most of it is built with fiber glass circuit board
>and the main  differences from
>  the ARCOS are:
>  1. This one uses receiving type sockets with a home-brew screen 
>capacitor
>      made from fiber glass circuit board. (Contact springs around the 
>tube screen ring)
>  2. The strip line isn't as wide (100 mm) as in
>the ARCOS so the tubes  sits closer together.
>      Strip line length is 250 mm.
>  3. The chimney is like a box around both tubes,
>made of glass fiber  circuit board
>      with most of the copper taken away.
>  4. Air is blown into the cathode compartment
>  Is there anyone on this list who knows if this
>is a known/published  design?

I've tried to find out about as many 4CX250 VHF amp designs as 
possible... but this is a new one.

-- 
73 from Ian G3SEK         'In Practice' columnist for RadCom (RSGB)
                            Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek