A little more background for the FCC (USA) gain restriction for HF amplifiers:

I believe that was a result of wanting to stymie CB use of ham amplifiers using 5-15w drive. 15-dB for 1500w implies 47w min drive.

The LDMOS being used for 1200w on 2m only require 3-4w drive; that is 26-dB gain! Likely the devices chosen by Elecraft for their KPA1500 have similar gain so they install attenuation into the drive path or change bias to lower gain (or both). My guess once the schematic is available any non-USA ham can bypass the input to enable lower drive requirements. A KX2 or KX3 ought to suffice.

Of course this would violate warrantee.

On a similar thought process, now that the KX3 is capable of 15w, I'm wondering if driving the KXPA100 harder than 8w will result in higher output? Would it be safe to do? I'm thinking 10w/100w. The KXPA100 I have drives easily to 110w saturated with about 4-5w on 80-15m, but requires 8w to achieve 70-80w at 6m.

73, Ed - KL7UW
  http://www.kl7uw.com
Dubus-NA Business mail:
[email protected]
______________________________________________________________
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