[Elecraft] Balun and Range of KAT2

[Bob - AG5Q]

Hi Ignacy,

With a high load resistance, the capacitance required for matching becomes
very small.  At higher frequencies the stray capacitance in the tuner may be
too large to allow an ideal match.
Here's an interesting java script that will allow you to enter various
combinations of load resistance and reactance and find the required L-C
values for the tuner:

http://www.hoflink.com/~mkozma/match19c.html

For example, with a 2700 ohm load, at 28MHz, the ideal capacitance is only
15.3 pf, which is less than the stray capacitance.

73/ Bob - AG5Q


----- Original Message -----
From: "Ignacy (NO9E)" <no9e@arrl.net>
To: <elecraft@mailman.qth.net>
Sent: Thursday, January 23, 2003 8:14 AM
Subject: [Elecraft] Balun and Range of KAT2


> My KAT2 matches very well on 1.8-10 MHz but the match is less certain on
> 14-28. With portable antennas, usually one of 10-12-15-17-20m bands does
> not match well ( SWR > 3) , and one or two are around SWR = 2.0.
>
> As an experiment, I tried matching a 2.7 K resistor. Matches on 160-30m
> were quick and to SWR <=1.2. Matches on 20-10 took much longer and SWR
> was 1.5 to 8. A simple test with Cs and Ls seems positive. Could my
> inductors or capacitances be wrong, or is this due to stray C/L and
> higher relative tolerances with smaller coils?
>
> Ignacy, NO9E