[Elecraft] KAP1500 High SWR wen unkeying with FT8

[Dick Dievendorff]

If you suspect your exciter is sending RF after releasing the amp T/R key line, you can add delay with the KPA1500 TR ADDED TIME menu item.  See page 32 of your KPA1500 owners manual.

  This menu item appears only if the TECH MODE menu item is enabled.

73 de Dick, K6KR

> On Jun 11, 2026, at 10:56, Ac9c via Elecraft <elecraft at mailman.qth.net> wrote:
> 
> I’m wondering if unkeying the amp with RF still coming out of the radio for a very brief instant could cause the radio to emit spurious RF due to the load impedance suddenly changing?  Also curious that there was no problem then suddenly in the middle of a great 6m opening - the problem appeared. This would indicate that something g failed/changed suddenly
> 
> Sent from the all new AOL app for iOS
> 
> 
> On Thursday, June 11, 2026, 1:44 PM, Andy Durbin via Elecraft <elecraft at mailman.qth.net> wrote:
> 
> I looked a my test report to refresh my memory.  The spurious RF spike duration was about 10 micro seconds.  I was impressed that my KAT500 could detect high SWR for a input so short.
> 
> Andy, k3wyc
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