No argument from me on this particular aspect of the difference from the
Jupiter to the Omni VII or Eagle. The next line in my post that was
quoted below was "I think that close in dynamic range has improved
considerably"
To me that was something I know going in. The Jupiter is going to fold
under contest operating type conditions where the Omni VII and Eagle
would not.
However, the areas that are of most concern to me are:
DSP artifacts like the "under water" sound, monkey chatter, etc.
A grating sound to the background band noise.
Birdies.
The AGC distortion effects of very short, strong noise impulses.
Receiver and transmitter audio distortion.
A full bodied, warm, clear sounding receive audio.
Over softening of the received CW note as the bandwidth is decreased.
Residual receiver hiss.
The receiver "fatigue" factor.
Transmit ALC overshoot.
Transmit IMD performance.
Any quantum leaps forward from the Jupiter to Omni VII or the Eagle for
these items? I expect there will be improvement in many of these areas,
I just don't expect to see the VW to Porsche kind of jumps. And yes, I
have owned both a VW Karmann Ghia and a Porsche 968. My impression of
the Porsche after owning it for a while was that I could not believe a
car could be this good. It was a quantum leap beyond anything I had
previously driven. But it was not the measurable qualities like
acceleration or braking, or cornering, it was how the car felt doing all
those things. The subtleties, the refinement. The same for what I find
in receivers, it is the subjective, how it sounds, how it plays kinds of
things that make the difference to me, not just the measurable specs.
Or perhaps quantum leaps backwards? Anyone find their Omni VII or Eagle
to sound EXACTLY like a Drake 2-B, or Collins S-Line, or Ten-Tec Triton?
73, Darrell VA7TO
On 13-01-16 09:52 AM, Rick - DJ0IP / NJ0IP wrote:
OH YES, IT WAS DEFINITELY A QUANTUM LEAP FROM THE JUPITER TO THE OM7 OR
EAGLE.
The biggest difference is in the Blocking Dynamic Range.
I found the Jupiter to be unusable in Europe on 40m at night when connected
to a good dipole.
You had to add so much attenuation that you couldn't hear weak signals.
Otherwise you had an S9+20dB noise blanket over the entire band.
So I modified it, and added jacks for connecting a preselector AND suddenly
the radio came to life.
I recorded audio files of this, sent them to Ten-Tec and as a result, the
OM7 which was still under development, was provisioned for adding a
preselector. The unit I received to test here in Europe had the preselector
connections wired to the back panel (that's an option, not standard).
On the dipole, I didn't have much problem with the OM7, though the
preselector helped it too, just as it had helped my OMNI VI+.
The OM7 was quite good once you turned on the attenuator.
The Orion was the only radio I owned or used at the time that did not
require a preselector under these conditions.
BTW, I found the K2 to be a total disaster without a preselector, so I
created a mod for it too. I sent this to Elecraft but got no response out
of them. However I believe the K3 does have provisioning for a preselector.
My K2 Mod is posted on my web site: http://www.dj0ip.de/downloads/ . (first
file)
When I put the OM7 on a 3 element 40m beam at 105 ft., and pointed it
northeast, the OM7 required the preselector.
It was either that, or add external attenuation.
In fact that was the only time that the preselector helped the Orion.
I did not test a Jupiter that night.
Sorry about speaking German in some of the files. I didn't even notice I
was speaking in two languages sometimes.
Back to the Jupiter:
Side by side, in Europe BEFORE the shortwave broadcast stations moved out of
the ham bands (above 7200 kHz), there was a world of difference between the
Jupiter and the OM7. Like a VW Beetle compared to a Porsche. Both from the
same designer, but WAY different.
You will also find the OM7 (+ Eagle and Orion) have much steeper filter
skirts and much better ultimate attenuation than the Jupiter.
Sounds like I am down on the Jupiter, but not so. I loved the Jupiter.
One of my favorite radios I ever owned or operated. I just don't care to
run a contest with it or use it on 40m in Europe without a preselector
KEEP IN MIND, in the states, you don't have the same challenges on the 40m
band that we do here in Europe, so I'm sure the differences are not as
apparent.
BTW, I tested a lot of different radios that night using that 3 element 40m
beam, made audio and video files of each.
The focus of my test was comparing the signal strength of a "Ghost Signal";
a signal that was quite audible on all radios, but in reality does not
exist. The Orion was proof of that. The Omni7 with a preselector was also
proof of that. It is interesting to compare how these different radios
compare in producing GARBAGE.
If you care to watch/listen to some of them, you will understand what I mean
about some radios being unusable 40m in Europe when you have a GOOD antenna.
Most radios had Ghost Signals all up and down the band, unless you switched
in a lot of attenuation. In most of the audio files, I was only monitoring
a "Ghost" signal and comparing its strength to that heard on the other
radios. The files are posted in the "RESULTS" section of a report called
"Transceiver intermod shootout on 40m in Europe",
here:
http://www.bavarian-contest-club.de/reviews/Transceiver-intermod-shootout-on
-40M-in-europe-;art32,565 .
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Darrell
Bellerive
Sent: Wednesday, January 16, 2013 7:02 AM
While the new radios were well received, and the advances praised, I did not
find any comments that indicated that there was any sort of quantum leap
made in the areas that most concern me.
73, Darrell VA7TO
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