Mike - NZ1MT wrote: > ...My power supply puts out a rock solid 13.8V, > K1 display indicated 13.4V key down.
You likely already know that those two different voltages are due to the normal voltage drop across the reverse polarity protection diode RF-D16. I neglected to mention that http://www.elecraft.com/order_form_parts.htm has ordering info for KAT1 version 1.30 firmware along with a short description of the purpose of the last revision: FWKAT1 KAT1 F/W Upgrade to 1.3. Increases matching range for loads that caused Plo message. The blue-trimmer KFL1-4 board alignment is very stable over time. I re-align my K1 every three or four years...not because it needs it, but just because I like tinkering with it! However, if I wanted to have maximum power outputs on each band in the 6 to 7 watt range, I'd need to align more often for that last little bit. The final alignment of the KFL1-4 filter board trimmers must be performed for the transmit function, not for peak receive function. The trimmer adjustments are far more critical for transmit output performance than for receive, so spending much time to tweak the receive alignment is wasted by the final adjustment of the *same* trimmers for proper transmitter performance, which alters all adjustments that had been made earlier in receive mode. The technique in the KFL1-4 and K1 manuals works well...it is important to align with the Pout set for 2 watts. Your KFL1-4 appears to be well-aligned already...consider that any further tweeking that you make is principally for educational purposes. :-) 73, Mike / KK5F ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html