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Old May 17th 08, 06:30 AM posted to rec.radio.shortwave
Telamon Telamon is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 4,494
Default Dual connection to same antenna

In article
,
RHF wrote:

On May 16, 3:55*pm, Telamon
wrote:
In article
,





*RHF wrote:
On May 15, 6:19*pm, Telamon
wrote:
In article ubQWj.2239$Yp.2147@edtnps92, m II wrote:
Telamon wrote:


Instead of just disconnecting the radio and ground you might also
want
to connect the coax center conductor and shield together at that
switch
point.


After giving this some thought, I got to wondering...


The induced voltage in the antenna has an instantaneous vector value.
Same on the outer sheathing of the coax. When the signal in the
sheath
is redirected to the inner conductor, it will, in effect, be changing
direction.


That changed direction will be in opposition to the signal in the
main
antenna wire.


Maybe. At some frequencies it will sum in opposition but not at all
frequencies.


I'm thinking that the length of the coax will in effect be subtracted
from the antenna length, not added as I had previously thought.


The antenna, apparently, is only as long as the wire portion MINUS
the
coax length.


This is all assuming that the switch is indoors, at the very end of
the
coax, not where the antenna joins the inner conductor.


- I suggested that you short the outer and inner coax conductor
- so the wire and coax would function common mode.
-
- Essentially the coax would just make the wire part look longer.
-


House -o======------------------------------======x


x======-------------------------------======o- Shop


-o PL-259 Plug
= Coax Cable
- Antenna Wire
x Shorted End


OK that works ~ RHF


-but- It brings the 'common-mode' noise from the
House to the Shop and the Shop to the House.
*.


- If he is not in his house to make the electrical noise
- then there should not be a problem right?
-
- What do you say to that Mr. Logic Person?
-

Telamon,

Houses are filed with . . .

'other' People {Family Members


How do you know he lives with other people?

Who each use Electrical Items

that Generate RFI and EMF Noise Artifacts


If he does live with other people he asks them to keep the noise makers
turned off.

PLUS - The ever present Stand-by-Mode

and Ready-On / Instant-On Devices


You turn them off or unplug them.

that Populate Every Home

each with it's own unique Electronic Signature.

Telamon - NO LOGIC REQUIRED :


I require logic.

It's Just Plain Common Sense. ~ RHF
.


Your common sense is nonsense.

--
Telamon
Ventura, California