As a relatively new ham operator, I have discovered the importance of not just having a resonant antenna, but also the importance of the location you are operating from, especially for portable operations.
I have not fully trusted myself with building antennas, so I’ve opted for buying a couple to meet my portable needs. I think this lack of trust has a lot to do with being in a poor location and relying on antennas that are too close to ground and surrounded by metal objects, such as caravans (when in the caravan park), and at home the fences and shed. I’ve learnt the truth of the adage: ‘height is might’.
Recently, I opted to buy the Mad Dog Coil 80m version, which has a range of 10m to 80m using a 5m extendable stainless-steel whip. The Mad Dog Coil is made in Australia by Marty Nelson – VK4KC. Marty also has a 40m version, and has recently developed the Blue Heeler, which uses 3-D printed base to fit two Mad Dog coils with antenna whips in a V-dipole configuration.
I have now tested the 80m version sitting on a tripod and while I received signals from the US, my 10w limitation was not enough to get a long path signal out of my QTH. I need a better location and some more elevation! I intend to test the Mad Dog Coil in the field, and will test it in the tripod, vehicle, and ground mounted configurations.
When I first set up the coil, I was happy with the VSWR of around 1.2:1 on 40m but had trouble tuning it to 10m and 80m. I could get a 1.6:1 on 10m and the tuner obviously brought this down to 1:1. I am pretty sure my location was the inhibiting factor. Overall, it worked well, and I will provide more detail once I perform the field test.
Mad Dog Coils can be purchased direct from Marty – VK4KC – using his website; plus, he has all the details on his products on his YouTube channel, including instructions on how to build the Mad Dog Coil yourself as a home brew. I’ve had email tic-tac with Marty, and he is very responsive and helpful, I cannot fault in anyway his customer service. Additionally, from my novice perspective, his product is well made and works.
Since purchasing the Mad Dog coil, I have seen others use a 5m wire on a squid pole and I tested this as well, with varying results. Again, I know the location was not the best, but irrespective, I made several contacts during the John Moyle Field Day (JMFD). I did learn a lot that day. I took my time to set it up, used both the whip and wire antenna on the coil, and made a few contacts. Each contact though, I was told I was down in the noise floor, but eventually registered a number of QSOs with a lot of persistence, repeating myself and of course patience of the other operators.
Learning what I did during the JMFD has boosted my confidence somewhat, and I intend to build a Micro Vert antenna for 40m and mount this on the roof of the house or the garage. Apart from making QSOs, I am finding the antenna challenges with amateur radio to be enjoyable. Stand-by for my in the field results of the Mad Dog Coil and once I have all the parts for a Micro Vert, I will write about that as well.
Cheers and 73
Dave – VK5GEM
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