Friday, July 6, 2012

KH6JRM's Amateur Radio Blog, post 163

An emergency 6-meter antenna

Although 6-meter openings to Hawaii are fairly rare, many of us amateurs on Hawaii Island look forward to times when the "magic band" is open.  As is often the case, when 6-meters and 2-meters "open up" to the U.S. mainland, amateurs in the central Pacific often don't have a decent 6-meter antenna available when propagation is favorable.  By the time  I get home to tune in the 6-meter signals, most of the action has already past and many signals have disappeared into the noise.  Such is the state of the ionosphere.

However, I think there is a way to keep on top of 6-meters without an outlay of additional funds.  Of course, it helps to have a rig that can cover 6 - meters--most of the current HF  rigs from Kenwood, Yaesu, Icom, and Alinco cover the band.  Or in my case, I can resort to an old Heathkit 6-meter rig in the storage room for such emergencies.

As for antennas, you may have a workable 6-meter antenna and not know it.  I found an article by Steve Hajducek, N2CKH, in the 17th Edition of ARRL's "Hints and Kinks For the Radio Amateur," p. 10-1, that may prove useful for those quick and often fleeting 6-meter contacts.  Steve found that the common 2-meter 5/8 wave base loaded antenna as well as 54-inch HF-mobile antenna masts are 1/4 wave antennas for 6-meter operation.  Steve says, "depending on the make and model of the radio, a software menu selection of antenna port or the addition of a diplexer may be all that is needed to get in on the excitement of 6-meter SSB or FM while mobile."  I've got to try Steve's idea one of these days.  I have a spare 5/8 wave 2-meter mag mount antenna that could be pressed into service.  Presently, the antenna is mounted on the metal roof of my garage and serves me quite well for repeater and simplex contacts.  The next step will be to move the old Heathkit from the storage box to the shack and see if I can find some 6-meter signals when propagation permits. 

The results of my mini expedition up an old plantation road above Laupahoehoe on 05 July were good.  Until the rains came, I managed to snag several good cw contacts with the venerable Yaesu FT-7 and the B & W apartment antenna.  The 40-meter counterpoise worked like a charm and most of my signals were 5 6 9  to 5 8 9.  Not too bad for 10 watts, a marine battery, and a compromise coil-loaded vertical.  Of course, operating from a quiet spot at the 2,000-foot level helped a lot....not to mention a clear shot to the northeast over nothing but the Pacific Ocean.  I cut the operation off after an hour or so because I heard thunder in the distance.  No sense getting fried by a stray bolt out of the blue.

I trust your 4th of July went well.

Until next time,
Aloha es 73 de KH6JRM--BK29jx15