Re: K3 SWR Accuracy - reprise

Posted by ab2tc on Nov 04, 2009; 10:12pm
URL: http://elecraft.85.s1.nabble.com/K3-SWR-Accuracy-reprise-tp3943810p3948632.html

Hi all,

This thread is getting rather long but I want to put  my 2 cents worth in. The huge discrepancy between the K3 indicated SWR and the LP-100 shown in Stewarts original post is *not* normal or expected. Either there is something wrong with the data or the K3. I am finding that the K3 readings tend to be a little on the "kind" side. I don't have a precision meter like the LP-100 but have come to find my MFJ tuner with its cross-needle analog meter reasonably trustworthy. My K3 readings are generally lower by 0.2 to 0.3, but no more. This is both at the 10W level and the 100W level, and both at nearly perfect match and SWR more in 2:1-3:1 range.

AB2TC - Knut

Iain MacDonnell - N6ML-2 wrote

I've been noticing some apparently anomalies in this area too, for example...

I have two dummy loads - one is a 2kW rated PalStar, which doesn't
appear to be exactly 50ohms (but close enough for usual purposes), and
a Bird Termaline, which is mil-spec 50ohms (and shows as such on a
sweep analyser), 150W rated.

With 100W at 3520kHz, into the Bird, my LP-100A shows 1.00:1, and the
K3 shows 1.0:1.
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