[Elecraft] Strong recommendation: MFJ 18xx-series single-band whips for KX3, etc.

[Bill Frantz]

I had this problem in spades finding an antenna to use on my 
Miata with a Yeasu FTM-10R, which does 2M and 70Ccm along with 
AM and FM broadcast. The FTM-10R manual says, “NOTE: An 
antenna designed with a matching device that forms a low DC 
resistance to ground may have poor recep on on the AM
Page 2
broadcast band.”

I finally parked the car outside our local Ham Radio Outlet and 
took antenna after antenna out to try them. I ended up with a 
Larson NMO-2/70 SH antenna which would receive AM and work on 
all the rest of the bands. In addition, it is quite small and 
doesn’t overwhelm the car.

73 Bill AE6JV

On 3/25/16 at 2:27 PM, pincon at erols.com (Charlie T, K3ICH) wrote:

>
>
>
>
>OR buy a 5/8 wave base-loaded 2m mobile whip -
>loads on 50-MHz very nicely.  That's an old trick
>for dual-band 6m/2m use.  Try brands like Larsen
>or Maxrad.
>
>73, Ed - KL7UW
>http://www.kl7uw.com
>"Kits made by KL7UW"
>Dubus Mag business:
>dubususa at gmail.com
>
>
>This only works for a 5/8  wave 2 M antenna where
>the base inductor (It's NOT a * loading coil)
>isn't tapped and grounded at one end.   In other words, if 
>there is a single connection to
>the antenna, this will work.
>If there's a ground connection such that the
>inductor is tapped up the coil it will not
>function on 50 MHz.
>The Larson LM series will work, but ones designed
>for the Motorola (NMO) base will not.
>73, Charlie k3ICH
>
>* A 5/8 wave antenna presents roughly 50 Ohms
>resistive and some level of capacitive (-J)
>reactance.
>In order to match this impedance, a series
>inductor is required to cancel the capacitive
>reactance, So technically, it is not a "loading" which would
>be designed to make up for the fact that an
>antenna is too short for a ¼ wave resonance.
>

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