Thursday, January 01, 2015

Portable Vertical Antenna for HF v2.0

Yesterday the CB antenna mirror mount that I ordered after I determined that my homebrew mount was too flimsy arrived. This morning I put together v2.0 of my portable vertical. Aside from the mirror mount, I also replaced the original steel drill rod stake with an 18" long piece of 3/8" diameter aluminum rod that was bought at Home Depot.

Before securing the mount to the aluminum rod, I used a file to put a point on the end that goes into the ground. I also roughed up the area that the mirror mount clamps to with the edge of the file, to help ensure a good grip.

Because the bolts which came with the mirror mount were a little larger in diameter than the machine screws I'd used with the homebrew mount, I had to replace the ring terminals on the radials with spade terminals.

Click on any pic for the full sized version.





I used the original nuts that came with the  mirror mount when putting it together, then used two 1/4x20 wing nuts to hold the radials on.







The finished mount with the collapsed MFJ-1979 whip:

Closeup of the mounted whip and deployed radials:


 
And finally, the whole shebang, now standing tall even with a slight breeze:



The FT-817ND tuned to 14.070 MHz running 5W QRP powered by a 12V SLA battery*, and my iPad Mini 2 running PSKer, tied together with KF5INZ's Easy Digi interface:


The temp today on my back patio in the shade was in the mid-30s and it starting feeling rather cold. I received signals from as far away as Michigan. I called CQ several times and almost completed a QSO with a ham in Georgia but there was too much QRM. But here's where pskreporter.info showed my signal reaching, from my home near Philadelphia, PA:


All in all, I rate this HF vertical as a success for portable 20M ops. I received many PSK-31 signals and got my signal out into the midwest. I'm looking forward to nicer weather when I can take the rig with this antenna to a nice hill and try for some digital QSOs.




* Note re the battery: I previously posted about using a lithium polymer battery sold for use with radio controlled cars and planes. What I didn't realize in my initial tests is that the radio powered up from its internal battery pack. When I tried it without the internal pack, the radio would not power up from the LiPO pack. It may not be providing the 3A needed for the rig to power on. It's very frustrating, especially since I spent about $50 on the LiPO battery and accessories. It might be useful for recharging the internal pack, however. In the meantime I'm going to use this 18 ah SLA battery. I'm looking at getting a 7 ah to 12 ah SLA battery which will be a lot lighter and easier to backpack.

Update 1/20/14: I got the battery working. AR15.com's Harlikwin messaged me about this, prompting me to look at it again. It turned out that I had the Power Pole connection on the negative side was bad. The little tab inside the PP wasn't fully seated. I was able to disassemble the PP, reseat it, and verified that I can power the radio from the lithium battery alone. w00t!!!!!

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