My Drive-thru days are OVER

March 11, 2008 10:47 PM

Ever since upgrading to General, I've been working on getting on HF. Aside from a local 10-meter net, I have yet to make a contact on HF (outside of Field Day, of course). Part of this has been due to the fact that HF just isn't very practical here in the dorm. Getting an antenna out isn't impossible, but can't be done in a way that I see as being very effective. So I've focused on getting my car to be my shack, of sorts. Replacing the ATAS-120A with a whip and tuner is just another step in the journey. At 12 feet from tip to ground, drive throughs are a thing of the past.

Look! My radio controlled car got big! You're looking at a RadioShack 102" stainless steel whip (Cat #21-903) mounted on a Diamond K400C mount on my Volkswagen New Beetle. The mount was purchased the a hamfest, from Burghardt. They didn't have the remaining pieces of the puzzle, so I ordered them from Burghardt's website when I arrived home (after not finding what I was looking for at the hamfest, of course!) The parts, a Comet AD-35M SO-239 to 3/8" x 24 adapter, and a Hustler QD-2 quick disconnect for 3/8" x 24 arrived on a warm sunny day in March, so why not put the pieces together!

Putting it all Together

As expected, everything went together well. The Diamond mount replaced the light-weight Comet mount, of similar design, on the driver's side of my trunk lid. It took a bit of time to get the K400C aligned properly so that the antenna would be vertical. It's still not perfect, but it's close. What makes it hard is this mount is meant to be beefy (technical term). It's not quite as easy as loosening the set screw, moving the plate, and re-tightening, as is the case with the lighter-duty mounts.

As running coax through my trunk lid is a royal pain in the butt, and not something I wanted to repeat again, I wanted to keep the coax I had already run, and use it with this mount. This meant using the coax with the SO-239 connector, and not one with an NMO connector, which I would have preferred for this. Thus, adapters had to be purchased. The AD-35M and the QD-2 went together well, and the mount doesn't budge. The quick-disconnect gives me the ability to easily remove the 102" whip and stash it away in my dorm room. Or, if I'm determined, fit it into my car. Getting the whip home was an interesting affair, as it comes in a long cardboard tube. I had the RadioShack employees watching me fit his giant thing into my Beetle!

Use

I have yet to do any testing with this setup. In between the whip and my FT-857D is an LDG AT-100PRO auto tuner. What I don't like about that combination? The TUNE button on the FT-857/FT-897 doesn't start a tuning cycle with the tuner. However, the AT-100PRO has a mode that will let the tuner function automatically (a nice feature in an autotuner!) where all that needs to happen is a key down, and it will start tuning. The relays in the tuner are pretty loud. I'll start a tuning cycle on AM with 10 watts, key up and wait for the grinding to stop. Once it does, release and key up again. If there's no more grinding, we're matched up. Tuning fresh takes 6 seconds or less (most of the time only a couple seconds) and tuning a frequency at or close to one that's been tuned before is only a fraction of a second. I'll do some testing between this set up and the ATAS-120a, and post the results here.