I've been using the LA-1K and HF-Auto behind a Yaesu FTdx101MP for almost 3 years now and have never had it kick out for any reason except once when I accidentally hit it with 200w drive. Ouch!?
My recommendations are: You should NEVER EVER drive the LA-1k with more than 60 watts. And you should NEVER consistently run the LA-1K at more than 300 watts output in FT4/8 modes. You should NEVER use "Mic Gain" to control RF output.?
It is your money but running the LA-1k at 1200 watts is nuts! It will damage the output transistors and shorten the amplifiers lifespan. I never run my LA-1K at more than 800 watts because to get any significant change in signal strength you'd have to go to 1600 watts. 1000 watts isn't going to make much difference. In my opinion, with a 1kw amplifier, anything over 800 is a waste of energy and unnecessary wear and tear on the amplifier finals.
I tune the HF-Auto with the FTdx101MP in RTTY mode and 10 watts output and the LA-1K in "Standby" mode. After the HF-Auto completes tuning, I switch the LA-1K to "Operate". Using this procedure, the drive power versus amplifier output power remains consistent across all bands. 40 watts drive results in 800 watts output. I believe that is due to the LA-1K always seeing a consistent SWR of 1.5:1 or less.
Another thing to watch for is intermittent problems in feedline, connectors, and baluns. As RF output power increases, these types of problems become more apparent. Baluns will overheat or burn out, connectors will arc, and feedline will become less efficient. The result is often intermittent HI SWR which will cause the LA-1K to "kick-out" due to HI SWR.??
Anyway, this is just my opinion and is based on my experience.?
73 kd4xr
Jerry
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