Thanks to all for the responses. Between the replies that made it to the list
and the private replies, I've been given some great information. I should
probably explain why I went with the amp. I'm aware that the difference
between 50 and 100 watts isn't dramatic. The antenna I am using is claiming a
6.8 dBd gain and I'll have it at roughly 19' above the ground. Allowing for
loss and optimism, I had figured on 6 being closer to real world gain. That
means ERP of 200 versus 400 watts. Given the choice, I'd prefer 400.
That wasn't the only reason though. During my practice runs, I noticed that
some stations would boom into my radio but others were barely audible, even
with the volume at maximum. Even though the preamp in the Mirage isn't
optimal, its better than nothing and could mean the difference in copying and
not.
It came down to a realization that I would get a modest improvement in TX and a
modest improvement in RX and would only cost $100. I can always sell it and
upgrade later but this seemed like a good place to start. I'll also be
upgrading the antennas for the next one as well.
One private reply was from a guy who owns this exact combination of amp and
radio. From what he said, I shouldn't have to use the remote at all. The rf
output of the radio will key the amp. I'll give this a shot and see how things
function. Apparently, I shouldn't blow anything up this way as long as I have
the rf out to minimum on the radio.
As usual, this list has been quite helpful and I appreciate all of it.
Steve
K4GUN
-------------- Original message --------------
From: "Ellen Rugowski" <ellenjoanne2003@sbcglobal.net>
> Honestly, I doubt it's worth it to even add the amp. Remember an S-unit of
> difference is about 6 dB of gain. So, to get an addtional S-unit of
> performance gain in the case of your IC-7000, you'd have to boost power 4
> times - to 200W. You;ld be better off just going to a higher gain antenna.
>
> 73,
> Ellen - AF9J
>
> ----- Original Message -----
> From: "Rogers, Ron"
> To: ; "VHF contesting list"
>
> Sent: Saturday, January 05, 2008 10:20 AM
> Subject: Re: [VHFcontesting] Dumb question about Mirage amp
>
>
> > The IC-7000 is already capable of 50 watts output on 144 MHz.
> >
> > The Mirage is capable of 100 watts
> >
> > Are you sure you want to go through the effort of adding this amplifier
> and keying hardware, etc. for only 3db gain.
> >
> > Ron
> > WW8RR
> > ________________________________
> >
> > From: vhfcontesting-bounces@contesting.com on behalf of k4gun@comcast.net
> > Sent: Sat 1/5/2008 9:57 AM
> > To: VHF contesting list
> > Subject: [VHFcontesting] Dumb question about Mirage amp
> >
> >
> >
> > I am aware that this is a dumb question. I'm asking it here because this
> crowd seems to be a lot easier on new guys than some of the boards and you
> guys are a lot more likely to actually know the answer. My question is
> about hooking up a Mirage amp to my IC7000. I found a model B-310G for $100
> shipped and figured for that price, I couldn't miss.
> >
> > So here is my problem. There are three connections on this unit. The
> SO239 connectors are clearly marked for the radio and antenna. The third
> input is marked "Remote Keyer" and it appears to be a 3.5mm jack. Not
> wanting to mess anything up, I went to the Mirage web site to see what I was
> supposed to do with this. I downloaded the manual and discovered its a
> remote keyer port. I'm serious. That's all the manual says. There are no
> instructions on when this should be used.
> >
> > So the question is, do I need this? If I do, which port do I insert it
> into in the back of the IC7000? I have a keyer port and a "remote" port
> back there, both with 3.5mm jacks. Finally, will just a standard audio
> cable with two 3.5mm plugs work or do I need something else?
> >
> > I feel retarded for having to ask this. Its my first amp and I really
> don't want to mess anything up. I wish the manual gave a better description
> of how to hook up and use the unit.
> >
> > Steve
>
> _______________________________________________
> VHFcontesting mailing list
> VHFcontesting@contesting.com
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