Re: 6M power chain working

ajparent1 <kb1gmx@...>
 

--- In BITX20@..., Rahul Srivastava <vu3wjm@y...> wrote:
Hi!

A DG MOSFET would certainly be an improvement. I had been thinking
on only BJT lines.

A good BJT can be excellent but most BJT designs are aimed at
high IP amplifiers. I've built one radio that used them MRF5xx
series in a norton push pull config with IP in the +35dbm range.
Nice but 100mA for the RF amp is high power drain for a portable.

At 6m a cascode connected pair of MPF102 jfets will work very well
with a good noise figure. I'm testig that to see if I'll use it.
The appeal is common jfets, easy to find, easy substitution.

Rather than purchase them from mkt I normaly salvage them from old
defuct TV tuners. The SMD BF989 or the 2SK series works well in most
cases.

My favortie source. Also old VCRs are a good source for balun cores
and PIN diodes.

Allison
KB1GMX

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