[Elecraft] FT-100 Tuning Knob

[Tree N6TR]

> Can anyone direct me to a source for the FT-100 tuning knob for use on my
> K2?  I understand that K2 users have depleted Yaesu's stock of them.

I guess I will come out of the closet.  I have a thoery on why so many
people aren't happy with the stock knob on the K2.  This ties into Vic's
recent post more than Earl's, but Earl's message was handy.

The "old" K2 firmware had a very significant limitation on how fast 
you could turn your VFO knob.  If you turned it fast enough, the radio
actually would not move frequency hardly at all.  You can try this
experiment:

1. Slowly turn the knob one revolution - taking about 2 seconds.  Notice how
far you QSYed.  It should have been 1 kHz if you are in the 10 Hz step mode.

2. Now, turn the know the same revolution as fast as you can...  how far did
you QSY?

3. Try turing the knob as fast as you can for a few seconds..  Note how far
you actually moved.

This means that it takes a LOT of finger grease to QSY up the band if you are 
turning the knob at any significant speed.  I believe this is the main reason
people are wanting a better knob - to reduce the pain associated with all of
this effort.

I identified this to Wayne as a significant issue for contest use of the 
radio - and he responded by greatly improving the firmware in the recent
release that has come with the KPA100.  The difference is very significant.
I no longer feel like I am pushing an elephant up and down the band.  

Along with this firmware change, it would be possible to use a different
encoder to replace the 100 step/revolution one.  Digikey sells ones that
are 200, 400 and 800 steps/revolution.  I have an 800/rev one and am
still evaluating it.  As long as I don't turn it too fast, I can QSY
around pretty quickly with minimum hand movement.  I can still turn it
so fast that the radio doesn't move very far, but as long as I traing 
myself not to do this, I think it will be okay.  

I would strongly suggest that anyone thinking they need a new knob check
out the improved firmware before making their final decision.  

If you are interested in the other encoders, check out the upper left corner
of this DigiKey page: 

http://info.digikey.com/T022/V2/0742.pdf and look at 102-1009-ND.  It is 
listed as 200 counts / rev, but in the K2, it gives 800 steps.  I would 
probably suggest the 100 counts / rev as a better choice than the 200 for
most people.  It is also cheaper.

Tree N6TR
tree@kkn.net