I wonder if any of you had your display unit for your Kenwood TM-G707 2/440 transceiver go blank and reboot even while the radio operates just fine.

If I move the wire with respect to the control head in a certain position this happens.

Is this just a case of dirty contacts between the little cable adapter and the control head or have any of you seen the wire in the cable actually break?

I guess this question applies to any remote display head models from any manufacturer. I had heard Kenwood units are especially prone to this behavior.

Thanks for your observations.

It may not be intuitive at first, but the answer, at least from an antenna pattern standpoint, seems to offer some hope.

It is difficult to calculate the feed-point impedance of a J-Pole perfectly since it is a tapped system. However, the calculations I ran for 430 MHz suggest it is somewhat close to a good match.

Here is the same J-Pole from Cebik’s collection with 146 and 430 MHz…

2 meter j-pole at 146 and 430 MHz.

The currents on the long vertical section act a bit like a long wire pointing straight up as shown in this comparison plot…

2m J-Pole Plot at 146 and 430 MHz

The pattern for 430 MHz, shown in green, is wild and certainly suggests this is not the ideal antenna for the job. However, if you look closely at the low elevation detail…

Close up of 2m J-Pole at 146 and 430 MHz.

…you will see a reasonable lobe of power at a low angle.

This simulation was done with the antenna at 300 AGL by the way.

So can you use a 2 meter J-Pole at 430 MHz and expect reasonable results. EZNEC suggests a cautious yes. However, be real sure about your SWR before you try this. It might not be what you expect.

A quick visit to a hospital addressed his wounds and he is already out and recuperating at home.

Great news…

There just one question though… How did the hunter use a small low power HT to access a repeater several counties away?

It turns out the hunter has a 2M/440 FM transceiver in his truck which can be set as a cross band repeater. This is exactly how he had it set up this particular morning while he carried a 440 FM HT with him. The mobile radio was tuned to the Warrenton 2 meter repeater.

So, the hunter relayed his signal from his HT to his truck and, in turn, to the repeater and finally to the hams listening during their morning commute.

Sure a cell phone would provide the same results, but there is a real chance they don’t work in the back roads of Rappahannock County and this was the case for Steve. Plus the cell phone would not allow the vocal support from a variety of concerned friends listening in on a party line.

So Steve relied on his amateur radio equipment to keep him “connected” to the world. Good thing he did. Here is the pathway Steve’s call for help took to bring the first responders to his side…

Entire communications path for ham requesting ambulance.

Steve’s equipment includes:

• Yaesu VX6R hand held transceiver
• Kenwood TM-708A mobile transceiver in cross repeat mode

This is an excellent example of how a hunter prepared for the worst using the best capabilities our amateur radio gear can provide. Thankfully, the morning commuters knew just what to do and helped keep up the spirits of the hunter.

This is real EmComm…
…and it didn’t even require a uniform.

The antenna that comes with your radio is probably about 8 inches long and is a compromise between convenient length and performance.

After market antennas are available and just a quick turn away from installation to your radio’s BNC or SMA antenna jack. Some are very short and provide the worst performance. Some are quite long and provide some amount of gain.

Problems may arise if you use a long antenna on a radio that is mechanically design to handle the stock and antenna.

I have an Icom Z1A HT that is broken at the moment because I used one of those 18 inch or so antennas on it. The strain of that extra length loosened the antenna jack’s grip on the case and eventually caused the conductor between the antenna center pin and the HT circuit board to break.

I still have the radio in pieces, but cannot quite find an easy way to access the point where re-soldering is needed.

If I had it to do all over again, I would not put that long whip on a consumer grade radio like we have for our ham radio hobby. To be honest, I think the performance of the stock antenna was just as good or better on 2 meters.

The moral of the story is to think through the mechanical realities of putting an after market accessory on your expensive radio gear. If you do, you may well decide that what you have is good enough.