The microphone connections on both rigs are unbalanced ( mic + and - Grnd).
Now there is nothing wrong with this setup mfrs. have been doing this forever.
The Orion, Jupiter and Peg are computers in a transceiver case and in an RF
environment. Standard RF grounding techniques do not apply. All computer
systems not only require special grounding techniques but also require special
power
supply techniques.
The NEC is concerned with safety not quality. (see balanced power systems vs.
standard power systems)
Where a lot of hams go wrong is when they try to use (1) ground for
everything and its just not going to work. This may work on standard rigs but
isn't
going to work on computer designed rigs.
There are (3) types of grounds that should be considered:
AC Ground (from the service panel outdoors to a grounding rod)
RF Ground
Lightning Ground (at towers)
And contrary to some on this list these grounds are separate and not
interchangeable. Each ground is a "special purpose" ground. (see broadcast
engineering
grounding)
If you are experiencing RF in your rig, it is not the rig that's at fault.
It is true, that if you take an ohm meter and measure the resistance from the
ground lug on the back of the Orion or Jupiter to the ground pin on the
microphone plug you will see approximately 3 to 4 ohms of resistance, this is a
no..no and can be easily corrected. Any resistance here looks like a path for
RF.
The Orion is a great radio and should not be confused with other mfrs. rigs.
Lets compare apples to apples and not oranges to apples.
There is only one other rig on the market today that is based on the same
technology as the Orion / Jupiter / Peg, and that is the SDR-1000 (FlexRadio).
(that I'm aware)
To help cure RF in the audio chain one might add an isolation transformer at
the mic input. (Jenson xfmrs)
My hat is off to Ten-Tec for always leading the way and not following. There
are just a few things in your stations construction that may have to be
modified.
I like my Jupiter, and not because its the prettiest thing I ever saw. (wish
it was black)
I also like my IC-756Proll, but like I said, lets compare apples to apples.
Just my $ 0.02
73
John / N0KHQ / St. Louis
Always on 18.130
Antennas:
You can build 'em better than you can buy 'em
Please visit the sites below:
http://www.hamuniverse.com/17mcoaxmox.html
http://www.cebik.com/n0khq.html
http://www.ssb-audio.com/forum/
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