[AMPS] Re: Ferrite Rod for 6M Amp

[Peter Chadwick]

Tom says:

	>I'm not talking about perfectly designed receivers, I was conveying

>how my FT-1000 actually measures.

That's damning with faint praise, Tom!!

	>The worse thing in my FT1000 was the MOSFET in the noise 
	>blanker left hanging on the IF strip even when the noise blanker 
	>was off. 

I've never yet found out why noise blankers always seem to screw up the
essentail parameters of a reciever, such as IMD. Also, designers seem to
have funny ides about MOSFETs - it's a dual gate MOSFET mixer that screws up
the spur performance of the FT102.

	>After repairing that design error, the next worse problem was the 
	>RF amp with four push-pull parallel FET's. 

Why do it that way? A push pull pair of 2N5109s with noiseless feedback
would probably be cheaper, and can give an intercept point more than good
enough for a +30dBm input intercept mixer. And to use +20dBm rx intercept
point, you need phase noise at -131dBc/Hz at 10kHz off (if you use 10/20kHz
spacing for IMD tests).

73

Peter G3RZP



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