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[VHFcontesting] Re: [WSVHF] Are Mirage amps THAT bad?

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Subject: [VHFcontesting] Re: [WSVHF] Are Mirage amps THAT bad?
From: alcortje@pcisys.net (Jesse J. Alcorta)
Date: Thu Jun 19 16:44:31 2003
I've owned two Mirage amps, a 25in160out model and a 50in300out model
and an RFC217.  The 160W model was dead straight out of the box but the
preamp worked great.  That was ten years ago.  The 300W model works
great as far as I'm concerned and I've had good success with it.  The
T/R switching requires some work as it doesn't drop out soon enough for
my taste but that is a personal choice.  The RF Concepts was the primary
workhorse of my station both at home and mobile.

Just because the amp says "25W in" doesn't mean that your going to get
the best service from it at 25W.  I believe that if some people would
take the time to observe their waveform with a scope or ask a fellow ham
to check their signal several KHz up and down to check for splatter they
would find that the amp would be better driven a few watts lower.  Fewer
complaints from the RFI-sensitive XYL too.  I think too many people
overdrive them to start with and that leads to problems.

If your worried about getting a lemon from Mirage, why not build one? 
Most manufacturers have plenty of transistors to choose from for
building something in the 150-500W class for 6M, 2M and 222Mhz.  Then if
you want PIN switches you got them.  Use relays if you like.  Add a
preamp if you desire.  Put in fan cooling, thermal protection, reverse
voltage protection, swr monitoring, blah blah blah....

There was an excellent article in 73 Magazine (could have been Ham Radio
Magaziine I don't recall) several years ago that showed a multi-octave
amp for less than the price of a new Mirage using a Motorola MRF175U. 
Sure it ran on 28VDC@10A but it also was good from 3.5-222MHz, required
no more than 5-8W drive for 200W out.  The whole construct was about the
size of an older HT.  No more risk in building one than buying it.  CCI
which advertises in QST offers several kits.  Most people with a couple
of free evenings and a weekend could build these.  Even DEM will be
offering kit amps using 28VDC.


73 de N0SWV  Jesse

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