Dave,
You've got an "interesting" problem there. It's hard to see how it
could be an RFI problem. However, you might want to seriously look at
your system grounding. If your CAT5 is "grounded" at both ends, it's
quite possible you're carrying a lot of AC current because of the likely
potential difference between the house and the barn. (See if you can
measure a current with a VOM.) If a big ground current is partly
passing through your rig, that might produce flaky results.
Optical isolation of one form or another is probably a good idea. Do
you ever have lightning in your area? A long CAT5 between buildings is
almost guaranteed to pick up surges from any nearby activity. I would
think about optical fiber or a WiFi link in your situation.
73 Martin AA6E
David Jordan wrote:
>
>
> Hi folks,
>
>
>
> This one has really got me wrapped around the axle.
>
>
>
> At my location I have a barn/ham shack about 1,000 ft from the house. The HF
> station is a TS-480. The station is connected to the Internet via a dial-up
> modem. I have been operating the station via the Internet for about seven
> years.
>
>
>
> Recently, I ran CAT-5 cable from the house to the barn. Installed Ethernet
> extender boxes ( www.netsys-direct.com <http://www.netsys-direct.com/> ) at
> both ends and have a nice 1Mbps connection between the two buildings. So, I
> now successfully operate the station from the house without using the
> dial-up connection which is SLOW. The station operates 160-6m. When I issue
> an instruction to place the TS-480 in transmit mode for CW the link fails
> and I have to walk down to the barn to un-key the radio. On all bands other
> than 7MHz and 10MHz this command is successful. With the radio output set to
> 5 watts and terminated into a dummy load the failure mode is reproducible.
> However, if I operate SSB I can run the legal limit to the dummy load or to
> ½ wave dipoles and experience no failure of the Ethernet link. Go figure!
>
>
>
> Even more interesting is the fact that this failure doesn’t not occur when
> using the radio with the CAT controller, i.e. sitting at the radio and PC
> sending commands from the keyboard of the host PC. Additionally, I do not
> have this failure when using the dial-up modem. It occurs “only” when using
> the Ethernet link and only on 7MHz and 10MHz.
>
>
>
> I’m beginning to think this is not an RFI issue. Are there any IP gurus out
> there that think, as I do, that perhaps I have a defective Ethernet extender
> box which somehow is reading the command string and resetting the link? I
> just can’t believe this is an RFI problem that is only specific to CW or AM
> mode but not SSB on those two bands.
>
>
>
> Thoughts are welcome,
>
> Dave
>
> Wa3gin
>
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