I think Marshall's post says it all.
You can't go wrong with either transverter. I reviewed the 2 meter Elecraft
and the 50 watt version of the DEM 2 meter transverter for QST. There was
very little difference in the measured receiver performance at the ARRL lab.
>From an empirical standpoint, both met and exceeded my 'homeboy' test:
ability to withstand the local signals generated by 1 kw output to a
reasonably large single yagi from K8ISK [20 miles distance but location
visible from the top of my tower] and K1RZ [9.9 miles distant and you all
know how loud he is]. Weak signals could be copied within 5 KHz of either
station and at 10 KHz you basically did not know they were there. The IF
strip was an FT1000MP with an IRC roofing filter but stock IF filters at 8
Mhz and 455 KHz.
The Elecraft has the best universal interface system I have ever seen. It
will handle ~-10 dBm to 5 watts by changing jumpers inside. With DEM if you
tell Steve what your IF strip is, he will generate a custom solution that
works first time every time for you. The DEM gives you the option of 50
watts which as Marshall says means no intermediate brick driver. However if
20 watts is sufficient for your driving needs, the Elecraft works just fine.
In my case I needed 50 watts to drive my 8877 and I actually bought the test
DEM transverter but I would have been hard pressed to decide which one I
wanted if 20 watts had been enough.
Finally I think both companies have outstanding service and support. As Bill
says, Steve is one of us and he goes the extra mile and more for his
customers. However I recently bought an Elecraft K3 and I have been
impressed with their technical support. Except when you deal with an owner -
like Steve - when is the last time you spoke or Emailed with a highly
intelligent tech support person? Elecraft's are and then some.
Neither of these was a 222 MHz unit but I would be willing to bet a fine
dinner in central Maine that their 222 transverters work as well as their 2
meter units.
73 Gene W3ZZ
World Above 50 MHz
FM19jd MD
50 => 10 GHz
Grid Pirates Contest Group K8GP
Member, CQWW Contest Advisory Group
-----Original Message-----
From: Bill Olson [mailto:callbill@hotmail.com]
Sent: Monday, February 04, 2008 3:40 PM
To: vhfcontesting@contesting.com
Subject: Re: [VHFcontesting] transverter questions
Elecraft makes fine gear. So does DEMI. It might bear saying, though most of
us KNOW it, that Steve, N2CEI, at DEMI is "one of us", namely a
VHF/microwave weak signal op and contester. The guys at Elecraft are top
notch engineers, but got into the VHF transverter business because they saw
a marketing opportunity. You won't catch them on 222 ssb during the vhf
contests!!
Many of you know Steve is my long time buddy and contesting partner, but the
above is still true..
bill, k1dy
> Date: Mon, 4 Feb 2008 14:28:02 -0600
> From: k5qe@sabinenet.com
> To: vhfcontesting@contesting.com
> Subject: Re: [VHFcontesting] transverter questions
>
> Hello to all.....we used the Elecraft transverters in our White Rover on
> 6M thru 432. They work very well and we have had no problems. We did
> this because DEMI is not makeing a 6M converter with 28Mhz output. The
> rest of the transverters from 902 to 3456 are DEMI's. In other rovers,
> we use all DEMI transverters....they also work very well, no problems.
>
> In the White Rover, we use an SDR 1000 for the IF. It puts out 1W on
> 28Mhz which works well with all the transverters.....Elecraft and DEMI.
> We just adjust the transverters for the right amount of gain and
> everything works very well.
>
> In those rovers using the DEMI's, we purchase from DEMI the "maximum of
> 10W of 28Mhz" input option. Then we set the drive radio to 5W on
> 28Mhz. In my opinion, it is VERY important to have a radio that will
> allow you to set the output power in the menu system for 28Mhz. Then
> you can't forget and run 100W of 28 into the transverters. I know a guy
> that does this almost every VHF contest. By having the radio enforce
> the 5W output on 28Mhz, you can't blow up your transverters(assuming
> that they have the 10W max type of input).
>
> In rover operation using TE brick amps, there is not enough difference
> to matter between these two choices. However, in the home station, I
> prefer the DEMI high power transverters, because they have enough power
> to drive a big amplifier without a driver stage.
>
> I feel certain that you would be very happy with either choice. Good
> luck es 73's Marshall K5QE
>
> Robert Cumming wrote:
>
> >Gene
> >
> >I run the DEMI unit on 222 and find it to have a very Hot
> >Receiver. Most times I don't even use my Mast mounted Preamp. It
> >drives my TE Systems brick to 120 W.
> >
> >I use a home brew switch box transfer the 28MHz IF of an Icom735
> >between transverters for 144 (Microwave Modules) 222, 432, 902 and
> >1296 (all Demi Units). I also use Steve's transverters on 2304, 3456
> >and 10368 with good results. The 2GHZ+ units use a 144 MHz IF
> >through a different switch box to an Icom 290H at 1W output.
> >
> >I have used other transverters in the past and find the DEMI units
> >deliver the best Bang for the Buck. Also in a contest situation they
> >outperform any Stand alone radio on any band above 6M. I continue to
> >use a Icom 756Pro on HF and 6M (its front end stands up well to
> >overload from nearby high power stations. Likewise for the DEMI
> >Transverters and a good 28MHz IF radio.
> >
> >Kudos to Sandra and Steve at DEMI for great customer service and
> >their continued support to the weak signal society.
> >
> >
> >VRY 73
> >Bob Cumming
> >W2BZY
> >QRV 160M - 9CM + 3CM (5760 next)
> >from EL98hr
> >
> >
> >At 11:58 PM 2/3/2008, Gene Gabry wrote:
> >
> >
> >>Hi,
> >>
> >>First, please reply direct with your comments.
> >>
> >>I am going to be adding a 222mhz transverter to my
> >>station and would like to hear opinions pro/con from
> >>users of the DEMI 222-28 and Elecraft XV222. How do
> >>each of these perform in contest conditions? I think
> >>the noise figure spec on the Elecraft is slightly
> >>better than the DEMI, according to the specs on each
> >>suppliers web site.
> >>
> >>Anyone using a Kenwood TS-2000 as the exciter? If so,
> >>how do you have your transverter configured? Do I need
> >>to modify the TS-2000, or will either of these be plug
> >>and play? It looks like I will need the AOS-28
> >>interface if I go with the DEMI unit. If I read the
> >>manual correctly for the Elecraft, I should not need
> >>an interface.
> >>
> >>>From a kit construction stand point, comments on how
> >>the two compare, parts count, difficulty to build,
> >>test equipment required?
> >>
> >>The TS-2000 manual is not very intuative as far as
> >>transverter operation. I think the keying line is the
> >>same line that would be used for keying a VHF amp, via
> >>the EXT.CONT connector? Comments.
> >>
> >>Thanks for taking the time to read and respond.
> >>
> >>I am hoping to be active on 222 SSB in the june
> >>contest.
> >>
> >>Respond with comments to either < n9tf@comcast.net >
> >>or < gene_n9tf@yahoo.com >
> >>
> >>73 Gene N9TF, EN52xg
> >>
> >>
> >>
>
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