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144MHz U310 N6CA

144 MHz preamp using U310

Some home brew last night  I have this type U310 J-FET   also for 50MHz
a very stable and low noise design  (N6CA)

 I could not tune  the input circuit tried all kind of L/C combinations

 The amp seems to work  okay  
But saw no S/N improvement on the IC706 144MHz  receiving.
Already there is an "antenna" noise increment upon connecting the antenna.
So improving S/N is not possible anyway this way.

 Also found that my LED reading lamp IKEA has  a nasty electro smog while having the preamp close to it on the desk.
No HF smog observed until now.

 Also 144 had a very bad drifting rattling noise moving over the whole 144-146 MHz from the south.
DeJa vue from my 2m magic days long time ago when I was an active 2M DX'r
we alway had to fight noise sources even here in the country.   

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