Jim Brown wrote:
> On Tue, 23 Dec 2008 21:22:22 -0500, Roger (K8RI) wrote:
>
>
>> My 144/440 duobander TM-D710 sets right between two
>> Samsung 226BW monitors while my HF rig is only about 3 to 4' to the
>> right. The HF-440 all mode rig in the shop with the KW amp is about 6
>> inches from another LCD monitor.
>>
>
> SANITY CHECK! Unless the shielding of your radios is beyond abysmal,
> spacing between your rigs and the monitors does not matter! What
> matters is distance between the radiating part of your transmitting
> antennas and the monitors.
>
Well, let me rephrase that then...I can set my duoband HT between the
monitors so the antenna almost touches both. That puts the HT less than
a foot from either of the Athlon X2 6000's and the Phenom 9950 quad core.
The gigabit network cable for one runs with the control cable for the
TM-D710 and the coax for both rigs runs in a bundle with the now CAT6
cables (was CAT5e) for about 8 feet before they separate. However the 4
runs of RG-6 (2 to the satellite dish and one to each of the two OTA
antennas with antenna mounted preamps) run in the same bundle AND
through 75 feet of conduit to the tower. From there the two to the TV
antennas run in the same bundle of LMR-400 (being changed to LMR-600) to
90' where the two UHF TV antennas are mounted about 8' above the Diamond
duoband 144/440 repeater antenna and about 15 feet below the stacked
12's on 144 and stacked 11's on 440.
The Yaesu 897D does not hear the computers with a portable antenna
mounted at the rig when it's less than 5' from the computers, router,
switch, and cable modem. I've not tried a local antenna on the 756Pro.
However, in the shop the Rigs are again within inches of the computers
and the 897D with a local/portable antenna does not hear them. The
slopers on 75 and 40 run within 30 feet of the computers and two runs of
CAT6. One amp runs 1KW PEP or CW for HF 1.8 - 30 MHz and 800 Watts on
6-meters, while the other is legal limit on HF 1.8 -30 MHz.. The
equipment gets moved back and forth between the two stations at times.
BTW after the CAT6 separates from the coax in the basement it runs
parallel and about 6 feet from the PVC conduit to the tower for 75 feet
where it passes within about 6 feet of the tower base and then 37 feet
to the shop.
Two points. The antennas for the TV are within feet of the business
ends of the 144/440 antennas and less than 10 feet from the tribander
at 100', or the top ends of the 75 and 160 meter antennas and about 20
feet off the end of the 40 meter slopers. Neither the HF/UHF/VHF all
mode or UHF/VHF duobanders hear the computers or monitors when the
antennas is inches away. However IF I lay the HT or multimode rig's
antennas against the plastic window on the side of the either computer
it will open the squelch intermittently. Nothing shows on either S-meter.
it will cause the squelch to break intermittently. I hear nothing on HF.
I've never tried laying the antenna against the CAT6.
OH, There are three coax cables carrying component TV and two carrying
audio from the 40" HDTV to the computer tuner on my right as well. There
is also a serial cable from the computer to the TM-D710 and another to
the Icom control interface. Ya can't get the computers, radios, TVs,
and antennas much closer than that without expecting to burn out something.
At one time I had some brief TVI when the neighbor to the South had some
football watching parties in his garage with only rabbit ears for an
antenna. I'd wipe it out when operating on two meters. I gave him a
good TV antenna that we hung up in the rafters of the garage which cured
the TVI. I then went over and drank beer with them when the football
games came on.<:-))
73
Roger (K8RI)
> 73,
>
> Jim K9YC
>
>
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