Michael E Fox (N6MEF) wrote:

My factory-assembled K3 is reading 1.0 SWR while my LP-100A and tuner both agree on about 1.4-1.5.

The KAT3's stray impedance (in bypass mode) may impact the SWR as seen by the K3's bridge, since this bridge is between the ATU and the LPFs. This effect would be more pronounced on the highest bands. Your external bridge is between the KAT3 and the antenna, so it may read differently from the K3 if any strays are present.

The "bypassed" state of the KAT3 is actually a per-band combination of L and C intended to cancel out the ATU's own strays. But compensation accuracy will vary from one KAT3 to the next due to the 5% tolerance on the components. So on some bands, the SWR in bypass mode might actually look closer to 1.0:1 with a load Z that is not quite perfect.

Still, all of these effects should be small, and I'll do some tests to see if I can duplicate an SWR discrepancy between the K3 and an external instrument.

73,
Wayne
N6KR

---

http://www.elecraft.com

_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Reply via email to