[Amps] K2RIW / W2GN 144MHz Linear

[Ian White GM3SEK]

Adrian Rees wrote:
>Hi all
>I have been slowly gathering all the parts to build a 144MHz Linear 
>based around a pair of 4CX250B valves (tubes to our US Cousins).
>
>Recently, a local amateur sold to me his collection of parts, including 
>a pre-drilled chassis, stripline and all the necessary parts to, what 
>appears to be, a W2GN Stripline Linear.
>
>However, one or two of the components don't appear to "fit" together 
>particularly well (ie the Stripline is out by about 5 or 6mm). Some 
>internet research has yielded the W2GN design in PDF format, and I 
>understand that this is a development of the K2RIW design. I am 
>wondering if the differences in the chassis and stripline components 
>are because what I actually have is a collection of components for a 
>K2RIW linear.
>
>With this in mind, does anyone know were I could get some information 
>on the K2RIW 144MHz Linear using 4CX250B's

The K2RIW design is for 432MHz only.

Fred Merry, W2GN developed a series of designs and kits for 50MHz, 
144MHz, 220MHz and 432MHz  that all used very similar metalwork except 
for the tuned circuits. The 432MHz amp was very closely based on the 
K2RIW, with a few improvements, but all the others were Fred's own 
designs.

Tubes used in these amplifiers have included pairs of 4CX250B/R, 
4CX350A, 8930, 3CX400A and 4CX400A, although not all tubes have been 
tried on all four bands.

The 50MHz, 144MHz and 220MHz designs were all published in 'Ham Radio', 
so if you've found those articles you have reached the source.
After his death, the 432MHz design was published in 'The VHF/UHF DX 
Book' (by permission of his estate) to complete the set.

There have been a few batches of metalwork made in the UK by GHP, one of 
which I had a hand in, so it's possible you have one of those.



-- 

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek