|
Hello,
I¡¯m curious what I would need to do to use a mobile mag mount for an HF whip without mounting it to a car. I¡¯m guessing I need to get a large sheet of metal to act as a ground plain. (Because of the lack of a car.)
Chris
|
For portable use I have used a clamp-on mount (also sold to make a hamstick dipole) attached to a metal stake. Sticking that into the ground made a usable antenna. In cases where I didn't think I had a good gound I attached some radials made with split zip cord and just laid them on top of the ground, or if in an upper story of a motel I would clamp to a balcony railing and droop the radials over the edge or spead around on the floor. I made contacts with this setup, but it was a bit cumbersome to carry along, so lately I have been using a relatively inexpensive QRP loop and it actually works a little better, plus it disassembles into a small easily carried package.
I still use the hamsticks with a mag mount when going mobile in my wife's SUV
=Vic=
|
I know I have said this before but I will again now without malice.
The manager of the property is behind me working to build out a working Hf/vhf/uhf station. They let me put a hole in the wall to pass coax through.
The owner doesn¡¯t want exposed antennas as the normal idiot landlord would.
I got flack for putting my dipole up with cable tv coax.
I would want to get ham sticks and mount them on a base. I¡¯m guessing a large sheet of metal will work instead of the car.
Chris
For portable use I have used a clamp-on mount (also sold to make a hamstick dipole) attached to a metal stake. Sticking that into the ground made a usable antenna. In cases where I didn't think I had a good gound I attached some radials made with split zip cord and just laid them on top of the ground, or if in an upper story of a motel I would clamp to a balcony railing and droop the radials over the edge or spead around on the floor. I made contacts with this setup, but it was a bit cumbersome to carry along, so lately I have been using a relatively inexpensive QRP loop and it actually works a little better, plus it disassembles into a small easily carried package.
I still use the hamsticks with a mag mount when going mobile in my wife's SUV
=Vic=
|
For your "sheet of metal" to be large enough to be effective, it would most likely be objectionable, too. I second the recommendation someone else gave you. Try using 1, 2, or 3 ground radial wires with the hamstick.??? As many as possible, in different directions, as horizontal as possible.? ? Use as small diameter wire as you can get and run them wherever you can hide them. Good luck. Bob WB8BEL
From: "Christopher Miller" <djmalak2k6@...> To: [email protected]Sent: Friday, April 3, 2020 6:44:55 AM Subject: Re: [BITX20] Hamstick Mag Mount
I know I have said this before but I will again now without malice.
The manager of the property is behind me working to build out a working Hf/vhf/uhf station. They let me put a hole in the wall to pass coax through.
The owner doesn¡¯t want exposed antennas as the normal idiot landlord would.
I got flack for putting my dipole up with cable tv coax.
I would want to get ham sticks and mount them on a base. I¡¯m guessing a large sheet of metal will work instead of the car.
Chris For portable use I have used a clamp-on mount (also sold to make a hamstick dipole) attached to a metal stake. Sticking that into the ground made a usable antenna. In cases where I didn't think I had a good gound I attached some radials made with split zip cord and just laid them on top of the ground, or if in an upper story of a motel I would clamp to a balcony railing and droop the radials over the edge or spead around on the floor. I made contacts with this setup, but it was a bit cumbersome to carry along, so lately I have been using a relatively inexpensive QRP loop and it actually works a little better, plus it disassembles into a small easily carried package.
I still use the hamsticks with a mag mount when going mobile in my wife's SUV
=Vic=
|
I haven't read all msgs in this thread closely but if you live in
an apartment with a balcony with a metal railing you might
consider a mag? mount centered on the railing and connect the
railing electrically to the coax feedline braid.
I had a modified CB magmount that was resonant in 15 M band that
was mounted to metal railing that way and was able to get many
reliable qso's between Canada prairies and Central and South
America. Anything to the North for me was a bit attenuated by all
the steel and concrete but to the South it was wide open
unhindered radiation area.
On 2020-04-03 6:20 a.m., Bob Fischer,
Fischer Technical Services wrote:
toggle quoted message
Show quoted text
For your "sheet of metal" to be large enough to be
effective, it would most likely be objectionable, too.
I second the recommendation someone else gave you.
Try using 1, 2, or 3 ground radial wires with the
hamstick.??? As many as possible, in different directions, as
horizontal as possible.? ?
Use as small diameter wire as you can get and run them
wherever you can hide them.
Good luck.
Bob
WB8BEL
From:
"Christopher Miller" <djmalak2k6@...>
To: [email protected]
Sent: Friday, April 3, 2020 6:44:55 AM
Subject: Re: [BITX20] Hamstick Mag Mount
I know I have said this before but I will
again now without malice.
The manager of the property is behind me
working to build out a working Hf/vhf/uhf station. They let
me put a hole in the wall to pass coax through.
The owner doesn¡¯t want exposed antennas as the
normal idiot landlord would.
I got flack for putting my dipole up with
cable tv coax.
I would want to get ham sticks and mount them
on a base. I¡¯m guessing a large sheet of metal will work
instead of the car.
Chris
For
portable use I have used a clamp-on mount (also sold to
make a hamstick dipole) attached to a metal stake.
Sticking that into the ground made a usable antenna. In
cases where I didn't think I had a good gound I attached
some radials made with split zip cord and just laid them
on top of the ground, or if in an upper story of a motel
I would clamp to a balcony railing and droop the radials
over the edge or spead around on the floor. I made
contacts with this setup, but it was a bit cumbersome to
carry along, so lately I have been using a relatively
inexpensive QRP loop and it actually works a little
better, plus it disassembles into a small easily carried
package.
I still use the hamsticks with a mag mount when going
mobile in my wife's SUV
=Vic=
|
Good morning Andy and all: I have had some luck using large steel cookie and or cupcake sheets under a good Mag Mount, preferably lying on the ground but with some luck on a dining room table with visual access to the direction in which I wanted to transmit.?
toggle quoted message
Show quoted text
On Apr 3, 2020, at 07:26, Andy_501 <andrew.webb.501.ve4per@...> wrote:
?
I haven't read all msgs in this thread closely but if you live in
an apartment with a balcony with a metal railing you might
consider a mag? mount centered on the railing and connect the
railing electrically to the coax feedline braid.
I had a modified CB magmount that was resonant in 15 M band that
was mounted to metal railing that way and was able to get many
reliable qso's between Canada prairies and Central and South
America. Anything to the North for me was a bit attenuated by all
the steel and concrete but to the South it was wide open
unhindered radiation area.
On 2020-04-03 6:20 a.m., Bob Fischer,
Fischer Technical Services wrote:
For your "sheet of metal" to be large enough to be
effective, it would most likely be objectionable, too.
I second the recommendation someone else gave you.
Try using 1, 2, or 3 ground radial wires with the
hamstick.??? As many as possible, in different directions, as
horizontal as possible.? ?
Use as small diameter wire as you can get and run them
wherever you can hide them.
Good luck.
Bob
WB8BEL
From:
"Christopher Miller" <djmalak2k6@...>
To: [email protected]
Sent: Friday, April 3, 2020 6:44:55 AM
Subject: Re: [BITX20] Hamstick Mag Mount
I know I have said this before but I will
again now without malice.
The manager of the property is behind me
working to build out a working Hf/vhf/uhf station. They let
me put a hole in the wall to pass coax through.
The owner doesn¡¯t want exposed antennas as the
normal idiot landlord would.
I got flack for putting my dipole up with
cable tv coax.
I would want to get ham sticks and mount them
on a base. I¡¯m guessing a large sheet of metal will work
instead of the car.
Chris
For
portable use I have used a clamp-on mount (also sold to
make a hamstick dipole) attached to a metal stake.
Sticking that into the ground made a usable antenna. In
cases where I didn't think I had a good gound I attached
some radials made with split zip cord and just laid them
on top of the ground, or if in an upper story of a motel
I would clamp to a balcony railing and droop the radials
over the edge or spead around on the floor. I made
contacts with this setup, but it was a bit cumbersome to
carry along, so lately I have been using a relatively
inexpensive QRP loop and it actually works a little
better, plus it disassembles into a small easily carried
package.
I still use the hamsticks with a mag mount when going
mobile in my wife's SUV
=Vic=
|
I have also more recently found metal lid on chest deep freeze
acceptable or tolerable as well.
On 2020-04-03 7:11 a.m., Steve &
Judy Levine wrote:
toggle quoted message
Show quoted text
Good morning Andy and all: I have had some luck using large steel
cookie and or cupcake sheets under a good Mag Mount, preferably
lying on the ground but with some luck on a dining room table with
visual access to the direction in which I wanted to transmit.?
?
I haven't read all msgs in this thread closely but if you
live in an apartment with a balcony with a metal railing
you might consider a mag? mount centered on the railing
and connect the railing electrically to the coax feedline
braid.
I had a modified CB magmount that was resonant in 15 M
band that was mounted to metal railing that way and was
able to get many reliable qso's between Canada prairies
and Central and South America. Anything to the North for
me was a bit attenuated by all the steel and concrete but
to the South it was wide open unhindered radiation area.
On 2020-04-03 6:20 a.m., Bob
Fischer, Fischer Technical Services wrote:
For your "sheet of metal" to be large enough to be
effective, it would most likely be objectionable, too.
I second the recommendation someone else gave you.
Try using 1, 2, or 3 ground radial wires with the
hamstick.??? As many as possible, in different
directions, as horizontal as possible.? ?
Use as small diameter wire as you can get and run
them wherever you can hide them.
Good luck.
Bob
WB8BEL
From:
"Christopher Miller" <djmalak2k6@...>
To: [email protected]
Sent: Friday, April 3, 2020 6:44:55 AM
Subject: Re: [BITX20] Hamstick Mag Mount
I know I have said this before but I
will again now without malice.
The manager of the property is behind
me working to build out a working Hf/vhf/uhf
station. They let me put a hole in the wall to pass
coax through.
The owner doesn¡¯t want exposed
antennas as the normal idiot landlord would.
I got flack for putting my dipole up
with cable tv coax.
I would want to get ham sticks and
mount them on a base. I¡¯m guessing a large sheet of
metal will work instead of the car.
Chris
For portable use I have
used a clamp-on mount (also sold to make a
hamstick dipole) attached to a metal stake.
Sticking that into the ground made a usable
antenna. In cases where I didn't think I had a
good gound I attached some radials made with
split zip cord and just laid them on top of the
ground, or if in an upper story of a motel I
would clamp to a balcony railing and droop the
radials over the edge or spead around on the
floor. I made contacts with this setup, but it
was a bit cumbersome to carry along, so lately I
have been using a relatively inexpensive QRP
loop and it actually works a little better, plus
it disassembles into a small easily carried
package.
I still use the hamsticks with a mag mount when
going mobile in my wife's SUV
=Vic=
|
A "large" steel cookie sheet would have to be a quarter wavelength square (10 meters or 33 feet on a side for 40 meters, 5 meters or 17 feet on a side for 20 meters) to be a "good" counterpoise - how large a cookie tray are we talking about?
Assuming a hamstick dipole is not possible, you might get by with a magnet mount on a large metal item, assuming the large metal item is at least the size of a small car. Bigger is better, and a more permanent mount than a magnet mount would be better, but you'll need to work with what you're able to do.
I would not, under any circumstances, attempt to transmit on an HF hamstick attached to a mag mount on any cookie tray that will fit in a conventional oven.
Ken, N2VIP
toggle quoted message
Show quoted text
On Apr 3, 2020, at 07:12, Steve & Judy Levine <sandjlevine@...> wrote:
Good morning Andy and all: I have had some luck using large steel cookie and or cupcake sheets under a good Mag Mount, preferably lying on the ground but with some luck on a dining room table with visual access to the direction in which I wanted to transmit.
|
For HF? What band and how big a chest freezer?
Ken, N2VIP
toggle quoted message
Show quoted text
On Apr 3, 2020, at 07:52, Andy_501 <andrew.webb.501.ve4per@...> wrote:
I have also more recently found metal lid on chest deep freeze acceptable or tolerable as well.
|
Lid is about 60" x 30" all metal and grounded to hydro ground. AA-30 analyzer shows resonant points at 18 MHz and 15 M band also.
toggle quoted message
Show quoted text
On 2020-04-03 8:35 a.m., Ken Hansen wrote: For HF? What band and how big a chest freezer?
Ken, N2VIP
On Apr 3, 2020, at 07:52, Andy_501 <andrew.webb.501.ve4per@...> wrote:
I have also more recently found metal lid on chest deep freeze acceptable or tolerable as well.
|
Hi Ken;
So sorry if I offended yours sense of proper RF radiation and propagation. You may have also objected to my use of two insulated sections of chain link fence mounted on 3 telephone poles with a bare-back KWM 2-A to run a nightly HF link on 40 meters between OSAN AB Korea to our CONUS MNCS in Missouri.
Steve, KC1ASO
toggle quoted message
Show quoted text
On Apr 3, 2020, at 10:06 AM, Andy_501 <andrew.webb.501.ve4per@...> wrote:
Lid is about 60" x 30" all metal and grounded to hydro ground. AA-30 analyzer shows resonant points at 18 MHz and 15 M band also.
On 2020-04-03 8:35 a.m., Ken Hansen wrote:
For HF? What band and how big a chest freezer?
Ken, N2VIP
On Apr 3, 2020, at 07:52, Andy_501 <andrew.webb.501.ve4per@...> wrote:
I have also more recently found metal lid on chest deep freeze acceptable or tolerable as well.
|
Hi, I have used an easy portable setup with reasonable results when on holiday. I too an unused camera tripod and made an L shaped metal bracket to fit to the top of it. I drilled a hole in the bracket to accept a converter this has an SO239 socket on one end and a 3/8 inch screw thread on the other end. The 3/8 screw fits my mag mount whip antennas... you may need something different. I have added a couple of photos below. I just used 1 radial 1/4 wave long but more would be better. The radials don't have to be in a straight line. This worked for me from a holiday cottage that had poor radio possibilities. It's never going to beat a full size antenna but is portable and doesn't need any supports. Hope this helps, Reg??????????????????????? G4NFR ???????????????????????  
|
You could also try the "Hamstick Dipole" listed here:
It seems some think it is good, others not so much.? I did try a 20 meter version for a short time.? I was too close to the ground and under a wooden deck, so I would not go by my experience.??
It is a compromise antenna, to say the least.? However that is what is required in an HOA restriction environment.??
I have read varying results for mag loops as well.? ?One day will get around to trying one, however, I also have an IC-7300 that has 100 watts out and would want it to handle that rig as well.? It makes the capacitor harder to find and more expensive.
Above are just thoughts and observations.? Use as you see fit.
73
Evan
AC9TU
|
I was going to suggest a few radials or a counterpoise wire but it was already mentioned by somebody else. There are people who will deny that things are working even while they watch them working. - shrug -
73,
Bill KU8H
toggle quoted message
Show quoted text
On 4/3/20 10:55 AM, Steve & Judy Levine wrote: Hi Ken;
So sorry if I offended yours sense of proper RF radiation and propagation. You may have also objected to my use of two insulated sections of chain link fence mounted on 3 telephone poles with a bare-back KWM 2-A to run a nightly HF link on 40 meters between OSAN AB Korea to our CONUS MNCS in Missouri.
Steve, KC1ASO
--
bark less - wag more
|
My best advice is: 1)open the mag mount and secure a 12" wire to the side in
common with the coax braid, 2) put some type of connector on the free end, 3)
figure out if you are going to mount it near the ground or on a mast, 4) use
the 12" wire to connect as many radials as you wish to the antenna mount, or
use one on a spool that you can wind up or extend wire for a given band, and
5) put the mag mount on a tripod or mast, you can create a steel plate adapter
to mate the mag mount to what supports it.
I have a tripod and mast arrangement; where I have a coil and a 16'
telescoping whip and a counterpoise (radial) for tripod, quick use, or a metal
bracket to set up two 16' whips horizontally for a dipole on the mast. I have
the same metal bracket for using two 20 m ham sticks in horizontal dipole
arrangement too.
|
I unfortunately don¡¯t have a private balcony. While I live on the 3rd floor tweakers and other degenerates would have access to the antenna unless I install it it inside my apartment. This works out because my living room is mostly empty save a few shelving units. I can install radials no problem. The ceilings are 10 feet tall so at least that is a plus.
I can put it outside temporarily as well now that I have coax running through the wall.
There is just 0 chance of installing it permanently outside.
Chris
On Fri, Apr 3, 2020 at 8:32 AM David < dokrent@...> wrote: My best advice is: 1)open the mag mount and secure a 12" wire to the side in
common with the coax braid, 2) put some type of connector on the free end, 3)
figure out if you are going to mount it near the ground or on a mast, 4) use
the 12" wire to connect as many radials as you wish to the antenna mount, or
use one on a spool that you can wind up or extend wire for a given band, and
5) put the mag mount on a tripod or mast, you can create a steel plate adapter
to mate the mag mount to what supports it.
I have a tripod and mast arrangement; where I have a coil and a 16'
telescoping whip and a counterpoise (radial) for tripod, quick use, or a metal
bracket to set up two 16' whips horizontally for a dipole on the mast. I have
the same metal bracket for using two 20 m ham sticks in horizontal dipole
arrangement too.
|
Not quite sure why you felt the need to flex and get personal, but let me return the favor.
From your initial email:
"Good morning Andy and all: I have had some luck using large steel cookie and or cupcake sheets under a good Mag Mount, preferably lying on the ground but with some luck on a dining room table with visual access to the direction in which I wanted to transmit."
So you've worked HF with an 8 foot hamstick sitting on a "large steel cookie tray" on the dining room table? And were able to successfully work DX in the direction of your dining room window?
Well, as has been clearly established long before this email thread started "Anything can radiate" as proven by QSOs accomplished using 100 watt light bulbs or cantenna dummy loads.
And it has also been clearly established that during the Korean War, propagation was a bit better than it is today. While only going back to the 1980s, my local club, for a public demonstration took a hybrid transceiver and "loaded up" a mattress spring and worked a few neighboring states on HF... but I don't recall that leading to countless hams putting mattress springs up on the roof of their house instead of straining a Dipole or other more conventional antenna.
Given the opportunity to put a modest antenna on top of his apartment building I suspect few would cite a hamstick on a cookie tray as their "go-to" antenna. I suggested, as did a couple other responders, that he consider a hamstick Dipole (efficiency wont be great, but with elevation and horizontal polarization, it could be a great option with minimal visual impact).
So how big were those chain link fence sections? I suspect they were each close to a resonant quarter wave length or odd multiple thereof...
Take care, stay safe,
Ken, N2VIP
toggle quoted message
Show quoted text
On Apr 3, 2020, at 09:56, Steve & Judy Levine <sandjlevine@...> wrote:
Hi Ken;
So sorry if I offended yours sense of proper RF radiation and propagation. You may have also objected to my use of two insulated sections of chain link fence mounted on 3 telephone poles with a bare-back KWM 2-A to run a nightly HF link on 40 meters between OSAN AB Korea to our CONUS MNCS in Missouri.
Steve, KC1ASO
|
My truck's no where near 33 feet in any direction and not only do I work 40 meters, I also work 75 and 160 from it.
While I don't recommend a hamstick much below 20 meters, 40 on a good day, a 75 or 80 meter hamstick (or two) also works quite well as a counterpoise. Also I've yet to see one of those hamstick dipoles work under 40 meters. On 75 meters, with 100 watts, a guy 20 miles away from me couldn't hear me. I was trying it as a camping antenna. I've since switched to an EFHW and that works great for camping.
If you're still going to use some kind of piece of sheet metal and a mag mount, remember you're going to want a ground strap for at least 40 and below.
Vince - K8ZW.
toggle quoted message
Show quoted text
On 04/03/2020 09:33 AM, Ken Hansen wrote: A "large" steel cookie sheet would have to be a quarter wavelength square (10 meters or 33 feet on a side for 40 meters, 5 meters or 17 feet on a side for 20 meters) to be a "good" counterpoise - how large a cookie tray are we talking about?
Assuming a hamstick dipole is not possible, you might get by with a magnet mount on a large metal item, assuming the large metal item is at least the size of a small car. Bigger is better, and a more permanent mount than a magnet mount would be better, but you'll need to work with what you're able to do.
I would not, under any circumstances, attempt to transmit on an HF hamstick attached to a mag mount on any cookie tray that will fit in a conventional oven.
Ken, N2VIP
On Apr 3, 2020, at 07:12, Steve & Judy Levine <sandjlevine@...> wrote:
Good morning Andy and all: I have had some luck using large steel cookie and or cupcake sheets under a good Mag Mount, preferably lying on the ground but with some luck on a dining room table with visual access to the direction in which I wanted to transmit.
--
K8ZW
|
Before a brawl breaks out, here are images from my front door. There is no way to be sure people will not touch my equipment. The dipole is hidden in cable tv coax which has worked so far.
Is it possible to get on the roof? Yes. Do I or the maintenance manager want to? No.
The baking sheet is a good idea to start, but the radials are a better option if I can get wire that doesn¡¯t sag. My dad worked for an am broadcast station and we dug up the radials to count them so the more the better.
Chris
On Fri, Apr 3, 2020 at 9:24 AM Ken Hansen < ken@...> wrote: Not quite sure why you felt the need to flex and get personal, but let me return the favor.
From your initial email:
"Good morning Andy and all: I have had some luck using large steel cookie and or cupcake sheets under a good Mag Mount, preferably lying on the ground but with some luck on a dining room table with visual access to the direction in which I wanted to transmit."
So you've worked HF with an 8 foot hamstick sitting on a "large steel cookie tray" on the dining room table? And were able to successfully work DX in the direction of your dining room window?
Well, as has been clearly established long before this email thread started "Anything can radiate" as proven by QSOs accomplished using 100 watt light bulbs or cantenna dummy loads.
And it has also been clearly established that during the Korean War, propagation was a bit better than it is today. While only going back to the 1980s, my local club, for a public demonstration took a hybrid transceiver and "loaded up" a mattress spring and worked a few neighboring states on HF... but I don't recall that leading to countless hams putting mattress springs up on the roof of their house instead of straining a Dipole or other more conventional antenna.
Given the opportunity to put a modest antenna on top of his apartment building I suspect few would cite a hamstick on a cookie tray as their "go-to" antenna. I suggested, as did a couple other responders, that he consider a hamstick Dipole (efficiency wont be great, but with elevation and horizontal polarization, it could be a great option with minimal visual impact).
So how big were those chain link fence sections? I suspect they were each close to a resonant quarter wave length or odd multiple thereof...
Take care, stay safe,
Ken, N2VIP
> On Apr 3, 2020, at 09:56, Steve & Judy Levine <sandjlevine@...> wrote:
>
> Hi Ken;
>
> So sorry if I offended yours sense of proper RF radiation and propagation.? You may have also objected to my use of two insulated sections of chain link fence mounted on 3 telephone poles with a bare-back KWM 2-A to run a nightly HF link on 40 meters between OSAN AB Korea to our CONUS MNCS in Missouri.
>
> Steve, KC1ASO
|
Thanks, the pictures help.
In an ideal world, I'd want to keep the radiating elements away from cable tv runs, mainly to avoid coupling issues, but also would be concerned about noise and/or RFI on cable tv run.
And since I'm dreaming of an ideal world, I'd also be concerned about RF safety with the radiating element within arms reach by anyone on balcony.
BUT, you aren't in an ideal world, you are where you are and you are trying to make the best with what you've got - the above concerns noted, you may not be able to do much better than you have already.
If you could find a way to run the radiating elements away from the cable tv runs, that might be an improvement, and an interesting thought might be to string a kind of "flat top" Fed with ladder line, running to an appropriate tuner that takes ladder line directly. (A flat top is essentially a random length dipole, each side equal length, Fed with ladder line.)
Good luck, stay safe,
Ken, N2VIP
toggle quoted message
Show quoted text
On Apr 3, 2020, at 11:58, Christopher Miller <djmalak2k6@...> wrote:
Before a brawl breaks out, here are images from my front door. There is no way to be sure people will not touch my equipment. The dipole is hidden in cable tv coax which has worked so far.
|
Vic WA4THR