Ladderline switch
 

I am putting up folded dipoles, one for each band I want to use. So far I
have 3 and I need to think about a switch .

I want to run all these ladder lines to a switchbox outside my cabin and
then run one coax thru the wall.

The ARRL handbooks have had suggestions for antenna switches but they were
all for coax. Has anybody built this for ladder line, and what would be
different?

First what do I connect the ladder line to, something like a set of banana
plugs would work, but could those plugs be in a metal housing, how would the
proximity of the metal affect the ladder line?? And the switching??
Would a double throw relay work??


So many questions...

Thanks for any answers

Uwe

On Sun, 24 Oct 2004 20:36:14 GMT, Jaggy Taggy
wrote:

I am putting up folded dipoles, one for each band I want to use. So far I
have 3 and I need to think about a switch .

I want to run all these ladder lines to a switchbox outside my cabin and
then run one coax thru the wall.

The ARRL handbooks have had suggestions for antenna switches but they were
all for coax. Has anybody built this for ladder line, and what would be
different?

First what do I connect the ladder line to, something like a set of banana
plugs would work, but could those plugs be in a metal housing, how would the
proximity of the metal affect the ladder line?? And the switching??
Would a double throw relay work??


So many questions...

Thanks for any answers

Uwe

You might get some ideas looking at mfj's new balanced line
switchboxes -- the 1706 uses banana plugs -- the 1706H uses ceramic
feedthrough insulators.

bob
k5qwg

You could use a few high current (30A) relays. Double pole double throw
types. If you nest (aka: boolean triangle) three of them, you could
easily switch four antennae into one common buss.

Something like the NTE 30amp unit (nicely spaced contacts, and lots of
space between poles.)

If you get ones with 12 or 24 volt DC coils, you can control the whole
matrix with common 3 pair 24AWG phone wire. (you could even get away
with 2 pair if you set them up with common ground)


Good luck and don't forget to use a few toroids on the DC feeds to the
coils!


'73
VE3PMK

Well, "it depends". Wide spaced, open frame, ceramic base relays are ideal for
switching ladder line. A knief switch is a good manual alternative. Best of
luck...

On 10/24/04 10:07 PM, in article
, "K9SQG" wrote:

Well, "it depends". Wide spaced, open frame, ceramic base relays are ideal
for
switching ladder line. A knief switch is a good manual alternative. Best of
luck...



I get the general idea of what type of relay to look for but where do you
get these???

And if I use banana plugs/binding posts at my entry points do I have to
install them in insulating material?? Something about running ladder line
through binding posts installed in a metal cabinet doesn't sound right....

Uwe

On Mon, 25 Oct 2004 14:49:09 GMT, Jaggy Taggy
wrote:

On 10/24/04 10:07 PM, in article
, "K9SQG" wrote:

Well, "it depends". Wide spaced, open frame, ceramic base relays are ideal
for
switching ladder line. A knief switch is a good manual alternative. Best of
luck...



I get the general idea of what type of relay to look for but where do you
get these???

Mouser, perhaps...


And if I use banana plugs/binding posts at my entry points do I have to
install them in insulating material??

The banana plug receptacles typically have a plastic collar to keep
them from touching the cabinet. If you'd rather go with ceramic
feedthrough insulators, they have them in all sizes at Surplus Sales
of Nebraska. Pricey, but they got 'em.

bob
k5qwg



Something about running ladder line
through binding posts installed in a metal cabinet doesn't sound right....

Uwe

On 10/25/04 12:18 PM, in article ,
"Bob Miller" wrote:

On Mon, 25 Oct 2004 14:49:09 GMT, Jaggy Taggy
wrote:

On 10/24/04 10:07 PM, in article
, "K9SQG" wrote:

Well, "it depends". Wide spaced, open frame, ceramic base relays are ideal
for
switching ladder line. A knief switch is a good manual alternative. Best
of
luck...



I get the general idea of what type of relay to look for but where do you
get these???

Mouser, perhaps...


And if I use banana plugs/binding posts at my entry points do I have to
install them in insulating material??

The banana plug receptacles typically have a plastic collar to keep
them from touching the cabinet. If you'd rather go with ceramic
feedthrough insulators, they have them in all sizes at Surplus Sales
of Nebraska. Pricey, but they got 'em.

bob
k5qwg



Something about running ladder line
through binding posts installed in a metal cabinet doesn't sound right....

Uwe




Yes, I wasn't suggesting to shorten the banana posts to the metal, thus
shortening the two antenna leads as well.

I was more thinking about the suggestion of keeping ladder line away from
objects, not nailing it directly to the siding of your house for example.

That suggests that this unshieleded line might be influenced by objects
close by. And along those thoughts I was wondering if bringing both lines
within fractions of an inch to a common ground, the metal box, might be a
good idea.

Uwe

Try http://www.action-electronics.com/nterelay.htm

they have a great index system. I would try something like the
R04-11D30-12 or something similar.