1.5 KW amplifier 2 meter conversion

[ki4zyv]

Hello I recently picked up a 1.5 KW amplifier I want to modify it for 2 m but I can't seem to find any information on the 1.5 KW version only the one 1 kw version 1.5 KW has six Fets instead of 4 like the 1kw The traces and combiners are somewhat different physically is it the same procedure for the 1.5 kw I need some help with this thanks in Advance by the way I tested the amplifier. At 87 MHz it is a Lo hi with 10 watts driving it gave me 1.4 KW at 50 votes

[Warren Stone]

If you are adventurous and willing to experiment, I feel the 1kW conversion procedure is a reasonable starting point.

Lift the coaxial cables at each FET input and output and terminate the splitter / combiner sections with 50 ohm resistors.  You can now sweep and measure the frequency response.  Capacitors will have to be changed, similar in manner to what was done in the original writeup.  Values to be determined.  FET input and output sections of the board are also similar, but layout is considerably different.  Again, the 1kW conversion instructions may provide a good starting point.  The FET output jumper location will have to be determined experimentally.  Even converting a 1kW amp, with a fully set up bench, all parts, known jumper locations (and after performing almost 50 conversions) requires several hours to complete.  Factor in a new learning curve, many more variables, and it's not a task to be taken lightly.

I have only one 1.5kW lo/lo amplifier.  It will have new capacitors as necessary to improve its 50MHz performance.  I'm not willing to use it for 2M.

If a 1.5 lo/hi were made available to experiment, I'd be pleased to see what can be done and share the results.  Maybe Brian WA1ZMS would be willing to update his conversion as well.