> If owners of Jupiter's and Orion's would get their ohm meters out and
> check their rigs as suggested in an earlier email they will find, on
> the Jupiter approx. 4 ohms of resistance from pin# 2 on the mic plug
> to the ground lug on the rear of the rig and on the Orion you will
> find approx. 6 ohms of resistance.
>
> Anything that's not absolutely at ground potential will look like a
> conductor to RF.....and that's a fact.
Your added ground wires will look like a conductor, a radiator, a pickup
loop to all sorts of garbage if given the chance. ... One foot of wire, firmly
grounded will STILL look like a conductor of RF at the right frequencies.
I'm going to say this one more time, and then get off the subject, since I'ts
clear I'm not getting through.
The point is not what the audio signal ground resistance from the mic
ground pin to the lug on the back of the cabinet is.
The point is where and how the audio signal ground meets the case
ground. There is no reason to strap the audio signal ground to the back
of the cabinet. If you follow the instructions for microphone wiring, it will
be bonded to the case at the mic connector.
IF YOU DO THIS PROPERLY AS IT IS DESIGNED, you will be doing
yourself a favor. Suggesting that Orion owners need to start running
wires grounding audio boards and RF/IF boards to the back of the case
and adding caps to the PTT lines is a disservice to those who will see
those posts, not know any better, and actually think they have to do it.
And if you REALLY think that T-T engineering messed up the design,
then you need to take it up with them, make your case, and get some
input before making these sorts of suggestions. And if you believe that a
foot of wire grounded at one end is "grounded", then you need to do
some reading on transmission lines.
It is also incorrect to confuse the electrical (safety) ground system around
the typical house, with a well designed RF ground system, no matter how
clean the connections are. The two systems should be bonded (at one
and only one point) for safety typically reasons, but they are NOT the
same. Electrical grounds are very nearly always, infinitely close to 100%
of the time, terrible RF grounds
Again, no flame intended, but you're missing a point.
Grant/NQ5T
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