Ham Radio Tower

[GaryM]

This photo shows the atnennas at the top of the tower.

Bottom: Force 12 XR-5 covering 10-12-15-17-20 meters
Next: M2 5 element 6M beam
Next: MFJ 2M/70CM beam
Top: Comet GP-6 Vertical for VHF/UHF

Havn't had too much chance to try the HF beam yet. But signal reports are excellant so far.

[Pat]

Gary, Did anyone in that mob count cadence? It actually looks lke a multiwinged high aspect ratio glider being run downhill to launch it.

But seriously folks, I'm jealous. I'm still quite a bit off from ham stuff on my priority list. I'll make a pitch for some kind of antenna farm and or sky wires after we move in which is an unknown time in the (hopefully not too distant) future. If I do some clever manuvering like installing my wifes kiln, utility sink, and storage shelves on her half of the 2nd floor of the shop, I'll have considerable leverage for consideration regarding my ham stuff.

Is there a story behind your antenna selections? My knowledge of store bought antennas, especilly with the "NEW" bands is way out of date.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[GaryM]

Well, we did through in a few Hup! Hup!s as we went down the hill!

The XR-5 has a total of ten elements, but only the 12M and 20M elements are driven by a feedline. The drivers for 10M, 15M, and 17M are parasiticaly excited. This allows five band coverage with one feedline.

The gains are in the mid 12 dBi, and mid 4's dBd. We all know that dBi is an isotropic (point source) antenna that can't be built, and a lot of manufacturer's rate their products that way. Force 12 supplies both specs.

Their elements are assembled with pop rivets, no sheet matal screws to loosen. The elements are also suspended below the boom where gravity wants to put them anyway! Most other antennas have the elements on top of the boom. Those are the ones you see with the twisted elements.

Here's a closeup so you can see how the elements are attached. BTW, the brackets holding the elements to the boom are all factory installed. You physically cannot pot the elements in the wrong place on the boom. Each bracket is labeled with the element name and number.

[Pat]

So tell us about the rotor and control. I suppose most of the antenna is at DC ground so grounding and static discharge are not big issues???

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[GaryM]

None of the antennas, other than the vertical, are at DC ground. Well that's not exactly true. The non driven elements on the 6M and 2M beams are grounded through the boom. But all the HF antenna elements are insulated from the boom with sections of electrical PVC conduit. I do still have to install my grounding panel and Polyphasers. Hope to do that in the next couple of weeks.

The rotor is a Ham-M I bought at a swapmeet a while back. It was manufactured about 1973. I refurbished and painted it. I also added a twistlock connector for the 8 conductor control cable. The units normally use an 8 conection terminal strip on the bottom of the unit with exposed screws. Not too good although they've been that way for years, it's always a trouble spot for rust and general corrosion.

I have obtained a unit to go inside the control unit that replaces the original control board. It's called Rotor-E-Z. Currently the control has three paddle switches. One each for brake release, CCW rotation, and CW rotation. It also has a knob for calibration of the indicating meter.

The Rotor-E-Z adds several features:
Automatic brake release
Use of the cal knob to select a heading and with one button sending the rotor to that position.
Automatically releasing the brake and backing the rotor uo for 1 second before turning in the selected direction.
RS-232 I/O for PC control.

I would like to have had a new rotor unit, but they are going for about $600.

[Pat]

New Controller? What else could it possibly do that you actually need done that your currrent planned installation won't do, cook breakfast or scratch your back?

Sounds great buddy, I'm even more jealous. By the way... You sent me scrambling to Google again as I was a Polyphaser virgin. Man, the stuff that happens while you aren't watching... next thing you know someone will develop a practical filament based electric light. If those Polyphaser thingies do half as good as they claim and are afordable they should be TERRIFIC.

I was more than a little concerned regarding lightning protection for any skywire to be put up due to to our abundance of thunderstorms. I will certainly be looking into Polyphasers.

You gonna computer control your beam's azimuth? Neat stuff, being able to store and recall aiming info and have the computer take you there like the modern "goto" astronomical telescopes.

Why for you no got elevation control too? Launch angle has been shown in some cases to make hoards of dB of difference. Variable height has been likewise shown to be better than a single height as you can tune ant elevation to operating freq to optimize performance. I realize your guyed system doesn't lend itself to that except in dead calm conditions and even then a big ant and a powerful rotor wold make me nervous with slack guys.



[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[egon]

I don't know about anybody else but I'd sure like to know what Gary and Pat are talking about! [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/confused.gif[/img]

[Pat]

OK Just for you Egon... The zigzag cam came out of the wobble box and messed up the threads on the thuzzle rod so we had to blitzle the snarfer lines to compensate for overhosen in the dragoids.

Actually for the most part (and probably as much or more as most posts) we have discussed the topic given in the title of the thread. Gary-O-M installed a tower to support an amature radio antenna with which he will communicate by other means than the WWW (believe it or not that is not illegal yet and they do it in Canada too.)

In addition to the mechanical aspects of the engineering project he mentions lightning precautions in the form of some NEWFANGLED product called POLYPHASERS which caused me to turn to Google to research as I was ignorant of their existance. After having studied on them, I now know that I will be getting some of them for my impending amature radio antenna installation. This exchange is no more difficult to follow than one on forrestry/wood milling where a reference is made to dogging a cant. (not cat) If you really want to know about any particular aspect of the thread, just ask as I am sure Gary won't mind answering questions about his installation. Alternatively, send me a PM with any questions and I will try to break it down for you.

Was yours a legitimate query or were you put up to this by the "THREAD POLICE?"

[img]/forums/images/icons/smile.gif[/img] [img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img] [img]/forums/images/icons/smile.gif[/img]

[egon]

Pat/Gary:

Tongue in cheek question [img]/forums/images/icons/grin.gif[/img] [img]/forums/images/icons/grin.gif[/img] with a grin on my face.

Always wanted a shortwave radio receiver but never got one.

Egon

[GaryM]

There are a lot of relatively inexpensive units on the market. I have a Sony ICF-2010 that I bought eleven years ago and it's been a good radio.

Check here: http://windupradio.com/shortwave/

It's even a Canadian company. These are pretty good radios for the money.