K3 vs Ft 5000

[KE7EOZ]

for MARS operation which radio would be a better choice K3 or yaesu FT 5000

[ZENKI]

The radio with the best TX IMD. That would be the FT5000 in class A.
The K3 has got less than stellar IMD performance, and its performance on the higher frequencies at full output is poor. On 6 meters
the PA is so bad it should really be operated at 50 watts and less. Elecraft just chosen the worst possible PA devices for their PA.
It would be great if Elecraft designed a decent FET amplifier for the K3 with decent IMD performance.

You can find the approved list here
https://ntc.cap.af.mil/comm/equipment/equipment.cfm

What I dont understand is how any ham equipment can be used on the MARS frequencies? The last time I checked I thought all equipment used on the MARS frequencies had to meet NTIA standards? Frankly speaking, ham equipment  in general  have such dirty transmitters in regards to their TX IMD and also IMD generated by bad ALC design.  I wonder why anyone would want to pollute the MIL frequencies with substandard equipment.

Get a Harris or Micom!

There are  so many good NTIA approved transceivers that would do a wonderful job. I have several MICOM radios and they work superbly. Lets be frank you dont need all the bells and whistles on ham radio equipment for channelized operation.

[W3LK]

What I dont understand is how any ham equipment can be used on the MARS frequencies? The last time I checked I thought all equipment used on the MARS frequencies had to meet NTIA standards?

The was never implemented for a variety of reasons, not the least of which was enforcement of the requirement on civilian-owned equipment. AFAIK, CAP was the only one to actually mandate NTIA compliance. They did that by outlawing the use of modified amateur radios completely.

There is a list of NTIA-compliant ham rigs, and adding an TCXO will make virtually any recent manufactured (within the last 15-20 years or so) rig compliant. The only real concern was frequency stability and drift for net operations. Except for folks using boat anchor rigs on the nets, it is pretty much a non-issue. FWIW, with a cooling fan in the case, my 1960s KWM-2A drifts no more than my TS570 after 30 minutes.

In the great scheme of things, NTIA compliance for MARS rigs is a solution in search of a problem.

Lon - NNN0OOR (Former MDE SMD, Deputy SMD, Assistant For Net Operations)
Southern New England Navy-Marine Corps MARS
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