ABout 20.2 inches is a quarter wave. Wevelength = 300/Freq in megahertz
300/146. Then divide that result by 1/4 to get your quarter wavelength
counterpoise.
Steve, K8SP
----- Original Message -----
From: "Tom Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, August 17, 2013 4:00 PM
Subject: Re: 2-meter Antenna Challenge
> Mark:
>
> So, now I'm thinking of two things here.
>
> First, the magmount I have is sealed, so I'm not sure how I would get to
> the
> shield of the coax to make the connection you describe.
>
> Also, I'm doing some mental calculations as to the length of the
> counterpoise.
>
> Can someone refresh me as to the formula you would use for that, keeping
> in
> mind that I'd like the antenna to perform best around 146
> megahertz--pretty
> much in the center of the band.
>
> Tom Behler: KB8TYJ
>
> ----- Original Message -----
> From: "Mark WZ0K" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Saturday, August 17, 2013 2:45 PM
> Subject: Re: 2-meter Antenna Challenge
>
>
>> Hi Tom,
>> On The antenna situation. Some years ago, I had a 5/8 wave mag mount
>> that I used in a window sill. It performed well enough. However, After
>> hearing about using a counterpoise, I loosened the antenna from the mag
>> mount and slid a thin piece of wire between the antenna and the mag
>> mount.
>> I
>> made sure it touched the metal part of the bracket that was connected to
>> the
>> braid of the coax. The wire was cut to a quarter wave. Suddenly my
>> reports
>> were better in all the repeaters, and I started reaching in to machines
>> that
>> I could not reach before. I hope this helps.
>>
>> God bless,
>> Mark
>> God loves You!
>> My personal website: Http://www.christiantraditions.info
>> The Blind Computer People List:
>> http://christiantraditions.info/mailman/listinfo/blindcomputerpeople_christiantraditions.info
>> Follow me on Twitter: https://twitter.com/TorgersonMark?refsrc=email
>> -----Original Message-----
>> From: [log in to unmask]
>> Sent: Saturday, August 17, 2013 11:32 AM
>> To: [log in to unmask]
>> Subject: Re: 2-meter Antenna Challenge
>>
>> Two suggestions:
>>
>>
>>
>>
>>> Hi, all.
>>>
>>> I hope I am not wearing out my welcome back to the list, but I have a
>>> challenging antenna situation I'm currently facing in the new faculty
>>> office
>>> I will be occupying starting this Spring semester.
>>>
>>> I currently have an old Kenwood TMV7A in the office, with which I have
>>> always had at least some luck, in terms of getting into our local
>>> 2-meter
>>> repeater. The repeater is about 15 miles from the University.
>>>
>>> However, in my new office, I am finding that the small mag-mount antenna
>>> I
>>> have always used simply does not allow me to reach the repeater
>>> consistently. Currently, I have the magmount sitting on a small metal
>>> bracket on the window sill in the office. It is right next to the
>>> window,
>>> so I would think that should help. However, I do not have much of a
>>> ground
>>> plain for the magmount. I also think there is some de-sensing going on
>>> with
>>> the steel of the office building, and with other surrounding computer
>>> equipment in the office complex.
>>>
>>> I do have a filing cabinet on the other side of the office that I could
>>> use
>>> as a ground plane, but the top of the filing cabinet is too high, and
>>> there
>>> is not enough space between it and the office ceiling to accommodate
>>> the
>>> magmount antenna.
>>>
>>> This obviously is a very challenging situation, and I also have to be at
>>> least somewhat concerned with appearance, in terms of not having an
>>> ugly-looking antenna that might draw more attention to what I am trying
>>> to
>>> do than I might want.
>>>
>>> Do any of you have any suggestions as to how to help the mag-mount
>>> perform
>>> better in this situation?
>>>
>>> Or, might I be better off considering another type of antenna, such as a
>>> J-pole of some sort.
>>>
>>> I would appreciate any thoughts.
>>>
>>> Tom Behler: KB8TYJ
>>>
>>>
>>
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