I had an earlier post about fabricating an antenna switcher for my
random wires, and one of the suggestions was to try the $11 RS a/b/c
video switcher. I did and there was no isolation at all. Don't waste
your time with this one.

I eventually put together a switcher using toggle switches. Works
great. Now I just need to make a nice finished case since I know it
works well.

A type F coax switcher that grounds unused inputs will work.

On 11 Sep 2003 07:21:43 -0700, (TommyBoy) wrote:

I had an earlier post about fabricating an antenna switcher for my
random wires, and one of the suggestions was to try the $11 RS a/b/c
video switcher. I did and there was no isolation at all. Don't waste
your time with this one.

I eventually put together a switcher using toggle switches. Works
great. Now I just need to make a nice finished case since I know it
works well.

TB,

First - Use a Metal Case for the Antenna Switcher [.]
- - - WHY ? Ease of Grounding Everything and RFI/EMF Reduction.

? Are you running Coax Cable or straight wires into this Antenna
Switcher from your Random Antennas ?

A "SOLID" Ground should be connected to the Antenna Switcher's Case
Ground.
- - - All un-used (Switched Off) Antenna Inputs should have heavy wire
(braid) connections to the Case Ground of the Antenna Switcher.
TIP: Put as "Much" Planning, Time, Money and Effort in to your
Grounding System as your Antenna System.

The Output of the Antenna Switcher should have some sort of Static
Surpression/Reduction to prevent damage to the radio's ESD sensitive
front end.

If you are using direct Random Wire Antenna feeds to the Antenna
Switcher: Then consider building in a 9:1 Matching Transformer into
the Switcher to offer some ESD/RFI/EMF protection and Isolation.

If you are using Coax Cable feedline for your Random Wire Antennas to
the Antenna Switcher: Then consider building in a 1:1 Matching
Transformer into the Switcher to offer additional ESD/RFI/EMF
protection and Isolation.

Recommend the use of a 'short' Coax Cable between the Antenna Switcher
and the radio(s).

iane ~ RHF
..
..
= = = (TommyBoy)
= = = wrote in message om...
I had an earlier post about fabricating an antenna switcher for my
random wires, and one of the suggestions was to try the $11 RS a/b/c
video switcher. I did and there was no isolation at all. Don't waste
your time with this one.

I eventually put together a switcher using toggle switches. Works
great. Now I just need to make a nice finished case since I know it
works well.

I eventually put together a switcher using toggle switches. Works great. Now
I just need to make a nice finished case since I know it works well.

That sounds great because it is flexible, i.e., because any and all antennas
can be grounded or even paralleled, and it can be expanded as your antenna farm
grows.

I assume you used DPDT switches.

Bill, K5BY

(WShoots1) wrote in message ...
I eventually put together a switcher using toggle switches. Works great. Now
I just need to make a nice finished case since I know it works well.

That sounds great because it is flexible, i.e., because any and all antennas
can be grounded or even paralleled, and it can be expanded as your antenna farm
grows.

I assume you used DPDT switches.

Bill, K5BY

No, spst. Would the dpdt make things like grounding easier? What did
you have in mind?

I'm about to buy some stuff online, so if I need dpdt in an improved
design I can get them easily enough along with the other stuff (new
iron, neon bulbs, etc.).

I'm pretty much hemmed in by power lines in a very modest lot. By
comparing my magnetic loop to my current wires, I'm getting just the
occasionally annoying noise from the wires/neighbors as is. I'm not
sure what using coax in my situation would do in the way of
improvement since I can't get the antennas themselves away from the
neighbors and the power lines, and my little corner shack is situated
about as best as it can re interference. All in all though, my
reception is okay but the R75 could do much better in another locale.

Thanks, I enjoy your posts here and on the Yahoo group.

....
TB,

First - Use a Metal Case for the Antenna Switcher [.]
- - - WHY ? Ease of Grounding Everything and RFI/EMF Reduction.

? Are you running Coax Cable or straight wires into this Antenna
Switcher from your Random Antennas ?

A "SOLID" Ground should be connected to the Antenna Switcher's Case
Ground.
- - - All un-used (Switched Off) Antenna Inputs should have heavy wire
(braid) connections to the Case Ground of the Antenna Switcher.
TIP: Put as "Much" Planning, Time, Money and Effort in to your
Grounding System as your Antenna System.

The Output of the Antenna Switcher should have some sort of Static
Surpression/Reduction to prevent damage to the radio's ESD sensitive
front end.

If you are using direct Random Wire Antenna feeds to the Antenna
Switcher: Then consider building in a 9:1 Matching Transformer into
the Switcher to offer some ESD/RFI/EMF protection and Isolation.

If you are using Coax Cable feedline for your Random Wire Antennas to
the Antenna Switcher: Then consider building in a 1:1 Matching
Transformer into the Switcher to offer additional ESD/RFI/EMF
protection and Isolation.

Recommend the use of a 'short' Coax Cable between the Antenna Switcher
and the radio(s).

iane ~ RHF
.
.
= = = (TommyBoy)
= = = wrote in message om...
I had an earlier post about fabricating an antenna switcher for my
random wires, and one of the suggestions was to try the $11 RS a/b/c
video switcher. I did and there was no isolation at all. Don't waste
your time with this one.

I eventually put together a switcher using toggle switches. Works
great. Now I just need to make a nice finished case since I know it
works well.

Would the dpdt make things like grounding easier?

Well, if you have any coax feed, it would allow for grounding the shield, too.

I need to build me another antenna switch array. When I listen to MW and LW, I
have to manually disconnect my feed's shield, which causes attenuation of the
signals from my SW antenna. So my switch box would have at least one switch to
do that.

I usually use DPDT switches, especially those with center off, so I have
flexibility in my final design.

The switch box I use now is left over for when I had a ham rig run through it,
too. It's mostly wasted now, because it needs changed.

I want use a plastic box for SWL-ing. That way I can isolate the coax connector
shells, except when switched together. The shack's ground is a husky ham
station ground per ARRL handbook, copper strap and all.

Vy 73,
Bill, K5BY