" Have we, in fact, established that this attenuator is enabled at any point of 
the tune cycle? Because if not, then we're all spun up for nothing."

KAT500 Serial Command Reference Revised 8/18/2021 firmware version 02.00 says:

"ATTN Enable Attenuator GET format: ATTN; SET/RESPONSE format: ATTN0; 
(disabled) or ATTN1; (enabled). Selects relay K22, which switches in an 
attenuator resistor. It may take a few milliseconds after issuing an ATTNx; 
setter before the relay changes. Firmware releases the attenuator if it detects 
power high enough to damage to the attenuator. Firmware normally inserts the 
attenuator during “full search tune” to present a more consistent load to a 
transceiver during tune operations. The attenuator is disabled if the tune 
power is too low with the attenuator in place."

This version was released so the document was compatible with firmware 2.05 
changes.

As I have said earlier in this thread I see no evidence that ATTN changes state 
during a "full search tune".

We are left with an attenuator design change that no one seems to understand 
and documentation that may not be correct.  Whether that is "spun up for 
nothing" probably depends on one's perspective.

Andy, k3wyc



______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected] 

Reply via email to