[Elecraft] 2-meter solid-state linear amplifiers with K3 2-meter option

[Sebastian, W4AS]

Owning and having owned several VHF/UHF solid state brick amplifiers, I have the following to offer:

I have four Mirage brick amps right now.  Two for 2 meters; one is a brown 10 in 80 watt output, and the other is a black 50 in 300 watt output amp. 

I use those for EME and meteor scatter with my K3, and an XV144 transverter for 2 meters with a sequencer.

I also have a pair of black faced amps for 222 Mhz and 432 MHz, with the XV222 and XV432 transverters.

All have served me well for many years, and I wouldn't hesitate to buy them again.

Lots have been said about Mirage pre-MFJ units vs after MFJ units, but I personally haven't experienced any issues with those; although I have seen the 'quality' of other MFJ equipment.  

I would however, say to stay clear of the TE Systems amps.  They are very popular and I have owned both the 2 meter and 6 meter versions, but they can't be trusted, and I may be in the minority of this view.

The TE Systems amps have no protection for the following:  high SWR, excessive input power, and temperature protection.  They are 'supposed' to have high temperature protection, but the ones I had failed when it was too late.  In addition, you won't find a schematic for the TE amps, and as a result, repairs and parts can be an issue.

There have been many times where my black faced Mirage amp has encountered a disconnected antenna, and it immediately goes into fault mode.  The TE Systems amps will happily continue to provide full output, without an antenna connected, and I don't have to tell you what happens to it.

The TE Systems amps are usually advertised in the used market as being 400 watt units, but the ones I had would do at best 300-350 watts into a dummy load with a Bird watt meter.

Of all of those, I would say the built in preamps usually just add to the noise and don't help in most cases.

73 de Sebastian, W4AS



On Jan 20, 2013, at 2:10 PM, Jim Brown <jim at audiosystemsgroup.com> wrote:

> On 1/20/2013 9:53 AM, Phil Hystad wrote:
>> Does anyone have the K3 2-meter option and use a solid-state linear amplifier?
> 
> I've not done so with the Elecraft units, but I own several 2M power brick amps, and studied the field before buying them.  My understanding is that of the moderate cost, medium power units (150 W output), the original Mirage (before MFJ) and the RF Concepts units, which I had heard had a common heritage, are the best.  They were built with several levels of drive requirement -- 10W, 35W, 50W, or something like that, as I recall.  Most, but not all, have built-in RX preamps.
> 
>> And, a friend suggested building my own 2-meter solid-state amplifier.  Has anyone done this and maybe I can hear a little about that too.
> 
> I would STRONGLY suggest that you avoid that unless you're a REALLY good RF design engineer with experience building stuff like that.  i would consider building a well engineered kit, but that's as close as i would get to it. :)
> 
> 73, Jim K9YC