Mag-mount as base-station antenna

Mag-mount as base-station antenna

Post by Tom Randol » Thu, 23 Mar 1995 18:30:15

I have a Larsen 5/8 wave mag mount that I want to use as a base station
antenna for 2 meters. This has the coil (and whip) that threads onto a stud on
the mag-mount base.

Plan A)***the whip/coil off the base. Build a new base with a mounting
       ***for the coil, with radials. The question is, how to do the
        radials? 5/8 wave long? +5%? Droop at 45 degrees? Also, will it need a
        tuning cap? I haven't been able to find much info on 5/8 antennas in
        the standard sources.

Plan B) Cut a small steel plate, slightly larger than the mag-mount base. Add
        radials. Again, how do I do the radials? Mag-mount the antenna to this
        plate just like a car roof.

Comments? Forget it and buy an antenna? This will be replacing a "coax
connector" 1/4 wave groundplane on a mast strapped to the chimney. The 1/4 wave
hasn't stood up to the weather very well... I don't really care too much about
gain, as I'm line of sight to 2 repeaters, and can hit others with a ***
duck.


 
 
 

Mag-mount as base-station antenna

Post by Robert Smi » Fri, 24 Mar 1995 04:00:00



>I have a Larsen 5/8 wave mag mount that I want to use as a base station
>antenna for 2 meters. This has the coil (and whip) that threads onto a stud on
>the mag-mount base.

>Comments? Forget it and buy an antenna? This will be replacing a "coax
>connector" 1/4 wave groundplane on a mast strapped to the chimney. The 1/4 wave
>hasn't stood up to the weather very well... I don't really care too much about
>gain, as I'm line of sight to 2 repeaters, and can hit others with a ***
>duck.

Larsen makes a mount that has 4 radials, uses a couple of ubolts to clamp
the mount to a pipe, and takes a standard Larsen coil like the one you
have. Talk to your nearest Larsen dealer.

--

I admire him, I frankly confess it; and when his time comes I shall
buy a piece of the rope for a keepsake. Mark Twain

 
 
 

Mag-mount as base-station antenna

Post by R0.. » Sat, 25 Mar 1995 04:38:18


I have a Larsen 5/8 wave mag mount that I want to use as a base station
antenna for 2 meters. This has the coil (and whip) that threads onto a stud on
the mag-mount base.

<< discussion of options omitted >>

I have a 1/4 wave mag-mount ant for 2 meters, sitting on my dining room
table, with a pizza pan under it (pizza all gone).  With my HT, I can
access 4 or 5 repeaters around the Cleveland area.  My house does not
have metal siding, or it might work worse.  I did not want to modify
the antenna, as I still use it occasionally as it was intended, on
the roof of my vehicle. -- Phil, AA8JO.