Topband: What's best (your opinion)

Tom Rauch w8ji at contesting.com
Fri Feb 16 06:34:30 EST 2007


> Just would like to ask You Tom, if You already tested for 
> that also the
> FT-990 and K2 and which results You found?

hi Petr,

I've measured several radios including the FT990 early K2 
but the information is buried in piles of things I never 
have time to get to.

If you look at the FT1000MP MKV page there is a schematic 
and description of the design error in the noise blanker 
circuit. Many different models repeat that error because the 
noise blanker is copied from one radio to another without 
ever fixing the problem that could be fixed at zero 
expense!!

http://www.w8ji.com/ft1000mk_v.htm

It is a bad practice to leave an unused semiconductor turned 
on with high gain and connected to a critical point in a 
circuit when it is not needed at all, and this repeats in 
many radios where they copied the noise blanker from one to 
the other.

If that is the case, all one needs to do is turn off or 
disconnect the offending semiconductor.

Let me tell you about an experience with the K2 I tested. 
The early K2 I measured had no sensitivity improvement at 
all on 160 meters when the preamp was turned on. The gain 
increased, but the weakest signal it could hear did not 
improve. With one single email to Elecraft they looked and 
found the problem, and within days corrected it in all 
radios. That almost NEVER happens today, and people should 
know that about Elecraft. It is quite a contrast from 
others.

A better list of radios and how they test is at Sherwood 
Engineering

http://www.sherweng.com/table.html

73 Tom 




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