Tuesday, August 23, 2005

MFJ1720S Antenna

After reading some of the reviews on eHam.net, last week I picked up an MFJ1720S tri-band antenna for my Yaesu VX-5RS. I wanted something that offered better transmission and reception performance than the stock rubber duckie.

The MFJ1720S is 19" long, so it's quarter-wave for 2M and 6M (due to end loading, I guess), and 5/8 wave for 70cm. It can handle up to 10W transmit power; my VX-5RS will Tx at 5W max. It's pretty whippy and I may tie some orange or yellow plastic to the tip to help prevent anyone from poking out an eye.

I got to use the new antenna for the first time Sunday night, when I checked into the 2030 MARC net (I really need to send in my membership app for MARC) on 2M. I asked for a signal report, and net control told me that while there was some background noise, they were able to understand me just fine over the repeater. From my listening point, there was some background white noise, and of course it's easier to setup with this thing than my homebrewed J-Pole.

So far, it works good on 2M but I haven't been able to try it out while talking to anyone on 6M or 70cm.


Carl Furst said...

I was going to purchase this antenna for my Yaesu 7R. The reviews on eHam.net are still pretty glowing, but you said that you were picking up some white noise.. How far away were the repeaters you were trying to hit and have you tried this yet on 6m or 70cm?

Dave Markowitz said...


I've since used it on 2M but not 6M or 70cm. Depending upon the weather it's pretty clear, although sometimes there's some background noise.

The repeaters I'm hitting around about 12 miles away.

Antenna Design said...

I am definitely looking into purchasing this antenna I just dont know where to go? Can someone please help me in where I should be going on the web if I wanted to purchase it asap?


Dave Markowitz said...


I've subsequently replaced the MFJ antenna with a Diamond MR-77, which I think is better. No matter which you get, do some additional waterproofing of the joints, e.g., where the antenna attaches to the mag mount base. I used liquid electrical tape like you can find at a hardware store.

For an online vendor try Gigaparts.com.