[Elecraft] SWR Adjustment (Don't Worry about it)

[Strode, Carl R]

Don thanks for reinforcing the "Don't worry about it" part.

I fiddled around with the KAT1 adjustments last evening with all sorts of dummy loads, RF probes, wattmeters, other rigs, antenna analyzers, etc.

The most valuable bit of awareness I came away with was that each method of measurement produced a significantly different result.  Coax lengths, number of connections, different test equipment, physical layout, etc, injected a lot of variables that are very difficult to quantify.

The very last thing I did was to compare the indicated output power and SWR from my K1 to the K2 indications when connected to the same known load via a Bird Wattmeter.  Neither rig will display exactly 2.0:1 SWR into a known good flat 100 and 25 ohm load.

On the K2, a 1.7 to 1.8 was the best I could get for both loads.  Adjusting the KAT1 R2 to maximum came into the ballpark - not spot-on, but at least on the same team.

With the KAT1, I figgered that as long as the C9 null was done properly, adjusting R2 for max indicated SWR will get me into the "Don't worry about it" Zone.

One interesting thing I did notice was that after dashing thru the menus, entering TUNE, adjusting CLS, CLP, output level, etc, the K1 microprocessor appeared to become discombobulated from time to time.  A momentary power-down always cleared the cobwebs and got it back to normal.