ZM-1

THE ZM-1 mobile antenna autotransformer is device when placed between the base of your mobile , center or base loaded antenna from 80 to 12 meters will aid in matching your mobile transmitter to the antenna with much higher efficiency than you will experience when just attaching the coax to the base of the antenna mount. Placing the ZM-1 near the antenna mount and attaching the flange mount to a good ground on the vehicle, the unit will connect between the coax and antenna base. Using the supplied banana plug attach a wire from the antenna base to the ZM-1, select the correct impedance for the band in use, it will give a noticeable power increase and bandwidth on the selected band. 10 meters is usually very close to the Z of the transmitter so using the ZM-1 on 10 meters is not necessary. An additional connector for straight through connection without using the UN-UN is provided, and it can also be used to prove the effectiveness of the ZM-1's efficiency .

The MARTRONICS ZM-1 is a new spin of an old device no longer available
that was produced by ATLAS many years ago.
The UNUN is unlike a BALUN in that instead of transitioning from balanced line to unbalance line, it transitions from unbalanced to unbalanced, and is referenced to ground.

It is very important to install the unit to a good ground, or it will not work.
So it will not work on a plastic car or boat without providing a good ground.

The chart below will aid in selecting the correct impedance to plug into.

Simply connect a coax from your radio to the SO-239 on the ZM-1 and depending on the antenna band selected connect the banana plug to the desired impedance. If you don't see the desired Z marking on the ZM-1 use the number closest to the desired impedance, It is an autotransformer and will still work well.

This unit also provides a DC ground, which reduces static build up, you will not hear the static popping normally heard when driving through dry dusty area.

BASE LOADED ANT. Z
            CENTER LOADED ANT. Z

3.8 MHz 16 22

7.2 MHz 15 19

14 MHz 12 19

21 MHz 16 29

To select other bands empirically select the position by checking the transmitter output power, or while selecting the antenna position, select the position with the highest rushing noise on the receiver.
At MARTRONICS we desire to always produce quality products , This unit is warranted for 1 year from date of purchase against manufacturing defects only, and will be cheerfully replaced or repaired if a defect is found. All other warranties expressed or implied are void.

If you are interested in other products or even have a suggestion for a new product, please feel free to call or write us, We are continuously looking for new products to produce, we also manufacture custom products for other companies.

HAVE FUN MOBILING 73.s

David Martin WA6TYJ
martronics@tcsn.net