Wednesday, March 14, 2007

Ham Radio to go

I'll bet you wondered why I had not posted in almost a week. As a rule I do not bore you with my Amateur Radio hobby as I have this info on my website, however I felt that you might be interested in some of my other hobbies besides photography that also includes machine shop work. I actually am a Machinest by trade, but no longer work in this field. This antenna is one of the reasons that I had not posted for a while other than to shoot these photos as I progressed with my new 80 meter mobile antenna for my Ham Radio ventures. The leading photo shows me tunning this antenna on my truck, however I am getting ahead of myself.

The second photo shows the stainless steel end caps being machined in my lathe with threading underway. You will notice one of the completed end caps on the cross compound of the lathe.

The third photo is the Delerine Core being threaded to accept the stainless end caps. The threading is being done in the lathe with a centre in the tailstock to keep everthing square, allowing the combined antenna parts to be perfectly square upon assembly. This Delerine mount is machined to a lenght that keeps the coil-form wiring from seeing the stainless-steel end -caps and detunning the completed coil assembly.

The Delerine core has been assembled with the completed assembly having been placed in the drill press vice in this fourth photo, where threading and tapping for the coil wire screw mounts is underway.
This photo shows the delerine core with coil form mounted in the lathe where a shallow thread form has been cut and I am placing the #12 gauge wire in place. A full size 1/2 wave 80 meter antenna that would be used for a base station antenna is 130 feet in length. The mobile version of this which is what I am building in these photos has to duplicate these dimensions. So what I am doing in this photo is winding fifty-five feet of wire on to this coil form. Add this to the five foot mast assembly and the Capacity Hat-Stinger top section and you have sixty-five feet which is half of the antenna. ( Of course this will be trimmed to length for the resonant frequency with my Antenna Analyzer)The other half of the antenna is the truck which has had all components bonded together to make up a efficient mobile 80 meter antenna when combined with the mast-coil and whip assembly-Confused? I cannot get into antenna design in this post, but take it from me, it can be quite challenging.

This photo of the Capacity Hat assembly is just that. I made it from stainless steel and then silver-soldered the components together. The stinger on the top is a screwed in assembly with the final length of the stinger to be trimmed for length once the antenna is assembled and in place on my mobile with my Antenna Analyzer.

This final photo is the finished coil with quick-disconnect in place ( the QD allows for my coils to be changed out depending what bands are open) and the shrink covering has been installed to weather-proof the coil. The coil has been on my truck now for several days with all trimming having been completed and so far I am quite pleased with my new 80 meter antenna. I have made contacts through-out Alberta, Saskatchewan and British Columbia and the northern states of Washington and Oregon so far.
All photos expand

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