[Elecraft] RE: K2 Frequency Alignment

[Dave]

Rich

Sorry to hear you are having such a problem setting your K2 on frequency. I
have to admit, setting the K2 to "nearly" the correct frequency is not easy
and something that Elecraft should consider for later models. Even with a
frequency counter linked to an off-air frequency standard it's not
straightforward. The only other realistic option would be to set the 4 MHz
oscillator by using another receiver and a short length of wire (around 18")
placed an inch or so from the control panel's 4 MHz crystal.

Allowing for a good warm up period (minimum of 30 minutes), keeping the
covers on at this stage to allow the K2 to thoroughly warm up. Using the
method suggested in the manual of connecting an external counter in parallel
with the internal one, I obtained the following accuracy:

1.8 MHz -11 Hz
3.5 MHz -11 Hz
7 MHz -17 Hz
10 MHz -21 Hz
14 MHz -16 Hz
18 MHz -30 Hz
21 MHz +5 Hz
24 MHz +3 Hz
28 MHz -5 Hz

That was with the thermistor and BFO modifications.

Dave, G4AON
www.astromag.co.uk/k2/

----- Original Message ----- 
From: "Rich Lentz" <ke0zx@cox.net>
To: "'KEN BROWN'" <elecraftk2@juno.com>; "Elecraft Reflector"
<elecraft@mailman.qth.net>
Sent: Sunday, July 27, 2003 2:25 PM
Subject: [Elecraft] RE: K2 Frequency Alignment


I am using that method and thus the question.

The two traces are right on top of each other and I can even hear and see
the slow (about every two seconds) zero beat, Thus the thing is within less
than 1 hz off.

BUT, even after alignment this way, running call pll, etc.  WWV at 10 mhz is
off by 30 hz and WWV at 20 mhz is off by 80 mhz, after a 30 minute warm-up
and stays there.  BOTH 10 and 20 are right on top of the harmonic and
exhibit the same zero beat.

Do you need to set the clock for something other than 4.00000000000000000 to
compensate for software counting inaccuracies.  It appears that the method
is the FCTR method and making both read the same frequency.