Merlin-7 KI4ILB wrote:
Now all I need to figure out is how to keep the 10 meter and 11 meter
antennas from interacting too bad or place them in such a way that the
interaction does something that is usefull...

Here's an idea. Use the 11 meter antenna for 10 meter
operation by switching in a series capacitor. All you
need to do is to neutralize the small amount of inductive
reactance on 10m caused by the antenna being a tad too
long. The capacitor could be switched in and out by a relay.
I get a value of ~330 pf to perform that function. The
SWR on 10m will actually be better than it is on 11m.

Or you could use the capacitor with the second 102 inch
vertical without having to cut it.
--
73, Cecil http://www.w5dxp.com

In message , Cecil
Moore writes
Merlin-7 KI4ILB wrote:
Now all I need to figure out is how to keep the 10 meter and 11 meter
antennas from interacting too bad or place them in such a way that the
interaction does something that is usefull...

Here's an idea. Use the 11 meter antenna for 10 meter
operation by switching in a series capacitor. All you
need to do is to neutralize the small amount of inductive
reactance on 10m caused by the antenna being a tad too
long. The capacitor could be switched in and out by a relay.
I get a value of ~330 pf to perform that function. The
SWR on 10m will actually be better than it is on 11m.

Or you could use the capacitor with the second 102 inch
vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression trimmer
capacitor to check that I could actually get a low SWR, measured it, and
fitted the nearest value disc ceramic (rated at 500VDC). I think it was
330pF. No problems with 40W.
Ian.
--

OK where can I buy a 330pf cap? Its only a 25 watt rig but I would like a
bit of overkill.
****es me off that Radio Shack is a cell phone store now. I used to be able
to walk into Radio Shack and the person there would understand what you
needed. Now if it does not have to do with cell phones or car audio they
just give you this dumb look..

Thanks
Joe

vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression trimmer
capacitor to check that I could actually get a low SWR, measured it, and
fitted the nearest value disc ceramic (rated at 500VDC). I think it was
330pF. No problems with 40W.
Ian.
--

Merlin-7 KI4ILB wrote:
OK where can I buy a 330pf cap?

Make it a silver mica or doorknob. I get mine at an
electronics supply store in Bryan, TX, close to
Texas A&M. Where are you located?
--
73, Cecil, http://www.qsl.net/w5dxp

"Now if it does not have to do with cell phones or car audio they
just give you this dumb look.. "

Heh.. went into my local Radio Shack and asked if they had any antenna
masts in stock. Guy goes and looks on the shelves. I say "I'd like a
TV mast, it's in the back if you have it, it's ten feet long" Guy
looks on the shelves some more, points to the mast brackets.

I'm like, "It's a ten feet long piece of steel pipe it wouldn't be out
here, it isn't out here, it wouldn't fit out here, it's in the BACK."
I look it up on the internet on the computer in the store and show them
that yes, they do have them in stock.

Of course, he doesn't think they've got any. Twenty minutes after I
walk in, I'm finally leaving with a five foot and a ten foot mast
section which they, of course, had. Guy is just incredulous that I'm
going to walk out of the store with a ten foot piece of pipe. They
then ask me if I need a cell phone ;-)

Dan

On Thu, 26 Oct 2006 22:53:48 GMT, "Merlin-7 KI4ILB"
wrote:

OK where can I buy a 330pf cap? Its only a 25 watt rig but I would like a
bit of overkill.
****es me off that Radio Shack is a cell phone store now. I used to be able
to walk into Radio Shack and the person there would understand what you
needed. Now if it does not have to do with cell phones or car audio they
just give you this dumb look..

Thanks
Joe

I've been able to mail order most any electrical part from Mouser. No
minimum order. And it puts you on the list for their huge catalog.

bob
k5qwg



vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression trimmer
capacitor to check that I could actually get a low SWR, measured it, and
fitted the nearest value disc ceramic (rated at 500VDC). I think it was
330pF. No problems with 40W.
Ian.
--

Ok which one would you recommend?

http://www.mouser.com/search/Refine.... f&N=1323038+0

Thanks
joe



I've been able to mail order most any electrical part from Mouser. No
minimum order. And it puts you on the list for their huge catalog.

bob
k5qwg



vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression
trimmer
capacitor to check that I could actually get a low SWR, measured it,
and
fitted the nearest value disc ceramic (rated at 500VDC). I think it was
330pF. No problems with 40W.
Ian.
--

"Merlin-7 KI4ILB" wrote in message
. ..
Ok which one would you recommend?

http://www.mouser.com/search/Refine.... f&N=1323038+0

Thanks
joe



I've been able to mail order most any electrical part from Mouser. No
minimum order. And it puts you on the list for their huge catalog.

bob
k5qwg



vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression
trimmer
capacitor to check that I could actually get a low SWR, measured it,
and
fitted the nearest value disc ceramic (rated at 500VDC). I think it
was
330pF. No problems with 40W.
Ian.


I once saw a 102" whip on a motor home that had literally been wound into a
4 " dia coil about half way up! It looked like one of those CB "big coil"
trucker antennas except it was all in one piece. I can only surmise that he
heated it and wound it around some sort of form. It shortened the thing down
to less that 5 feet. But, then, wouldn't that take the temper out of the
steel and make it flop over the next time it was hit? There was also no
evidence of heating, either; it looked like it had been formed at the
beginning of its life. Anybody ever see anyone do this before. If so, how
was it done?

73

Jerry
--

"Jerry" wrote in message
...

"Merlin-7 KI4ILB" wrote in message
. ..
Ok which one would you recommend?

http://www.mouser.com/search/Refine.... f&N=1323038+0

Thanks
joe



I've been able to mail order most any electrical part from Mouser. No
minimum order. And it puts you on the list for their huge catalog.

bob
k5qwg



vertical without having to cut it.

I did exactly this (20 years ago). I used a variable compression
trimmer
capacitor to check that I could actually get a low SWR, measured it,
and
fitted the nearest value disc ceramic (rated at 500VDC). I think it
was
330pF. No problems with 40W.
Ian.


I once saw a 102" whip on a motor home that had literally been wound into
a 4 " dia coil about half way up! It looked like one of those CB "big
coil" trucker antennas except it was all in one piece. I can only surmise
that he heated it and wound it around some sort of form. It shortened the
thing down to less that 5 feet. But, then, wouldn't that take the temper
out of the steel and make it flop over the next time it was hit? There
was also no evidence of heating, either; it looked like it had been formed
at the beginning of its life. Anybody ever see anyone do this before. If
so, how was it done?

73

Jerry
--







Wouldnt be that hard to do, You can retemper the steel if it gets soft and
the discoloring will buff off.
tempering metal takes some specific knowledge and experience. Ive done it to
tools and had some success but I have also made them to brittle and they
break.

Of course it may have been one of those big coil antennas