Author Archives: David Prutchi

I was cleaning up the basement, and found a box with my old pictures.  This one brought me fond memories.  This was my house (well, my parent’s house) in 1980.  Back then my callsign was “HC1DT.”  I had a TH3 on top of a tall tower, a 10m 3-element beam, and a bunch of home-made 2m verticals and beams.

As I had mentioned in the reflector discussion, my municipal permit allows my dish antenna to be up to 15 ft in diameter, so a project that will possibly precede the erection of the two towers is to expand the diameter of my EME dish from 12 ft to 15 ft.  I’ve been looking at how other hams have done it, and I think that the following are the best examples of what I would like to do:

This increase in diameter should have a theoretical gain change from 11.3dB to 13.6 dB at 1296 MHz.

I would be interested in knowing any experiences by other hams who have modified their dishes for larger D.  Anyone tried doing it to a Tek2000 dish?

I have received approval from the XYL for expanding my antenna garden, so I’m planning the projects for the upcoming fall and spring.  NJ law allows me to put up a 70 ft tall tower (excluding the antenna) without interference from the township, so I’m planning to take it all the way to that height.

The tower next to the house can be supported against the outer wall of the house, and I’m intending to place a 6-element HF beam and a a large 2m/70cm EME array on top of that tower.  My limitation is a 16 ft boom so that I can keep within 15 ft of my property line.  That’s certainly enough for a large, high-gain array.

The second project is to elevate the current 12 ft microwave dish to expand my horizon.  This will need a very heavy-duty, self-standing tower because of the wind load presented by the dish.  I need to take some measurements and see what would be the best compromise between height and achieved minimum inclination, but I feel that will fall somewhere around the 30 ft range.

I’m currently looking at the specs of ROHN towers, and would love to hear feedback from current users under similar load conditions.

PS.  Finishing the power amplifiers for 1296MHz EME right now… see you soon on the Moon at 23cm!

It’s July 20, 2019, and I am invited to a private screening of the CNN Apollo 11 documentary, followed by a party with my fellow nerds, so I don’t really have time today to work the sats. It’s 102ºF outside, so not a good day to tweak the antennas either, but I nevertheless wanted to do something space-related to celebrate the 50th anniversary of the Apollo 11 Moon landing.

As a compromise, I decided to test a Trivec-Avant AV2040-2 SATCOM antenna indoors to see if it would be suitable as a portable antenna in the VHF and UHF ham bands.

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CLICK HERE for a detailed writeup  with high-resolution pictures in .pdf format.

The GOES-East (GOES-16) satellite (GOES=Geostationary Operational Environmental Satellite) operated by NASA and the National Oceanic and Atmospheric Administration (NOAA) is exactly due south of my QTH and provides a view of Earth centered right at my longitude (75°W).

GOES-16 transmits two interesting direct services:

• The EMWIN (Emergency Managers Weather Information Network) service contains weather forecasts, warnings, graphics, and other information directly from the National Weather Service in near-real-time.
• The HRIT (High Rate Information Transmission) service broadcasts GOES satellite imagery data and other weather-related products.

I wanted to experiment with receiving these services from the GOES 16 satellite, and to do so, I added a small grid parabolic antenna to the Az/El boom that drives my 12’ EME dish. I purchased this antenna on eBay®. It is an Altelix WiFi 24dBi 2.4GHz parabolic dish with N-male connector that sells for $30:

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This is the latest addition to my antenna farm.  It’s a 12 ft mesh parabolic antenna on a heavy-duty AZ/EL rotator.  My intention is to use it for 23cm and 3 cm EME, amateur DSN, as well as for next-generation amateur satellites/CubeSats and (hopefully) planetary probes.

Fortunately, my wife doesn’t mind my weird hobbies, my deed doesn’t have HOA restrictions regarding antennas, and New Jersey has a specific law that prohibits municipalities from adopting zoning ordinances that prohibit construction or use of antenna structures by federally licensed amateur radio operators (Act from Assembly No. 3641 of the State of New Jersey, 211th Legislature, introduced January 10, 2005)!

Thanks to the nice people at the municipal office, I was able to get a zoning/construction permit from my township with no issue.  The construction inspector already gave me approval on the footing, so now it’s time to load a feedhorn and start to QSO off the Moon.  The antenna is smaller than the maximum I requested in my permit, so I can still grow it by another ~3 ft in case I feel the need for a few more dBs.

Of course, I’m already thinking about my next antenna project.  My thought is a tall tower to support a very large 2m/70cm EME array along with a 6-element HF beam.  According to NJ Act 3641 I can put up a 70ft tower, and then place the antennas on top of that:

“No governing body shall adopt a zoning ordinance that prohibits or has the effect of prohibiting the construction, maintenance or use of an antenna and support structure therefor by a federally licensed amateur radio operator. Zoning ordinances may reasonably regulate the location and height of those antenna structures for the purposes of health, safety or aesthetics; provided, however, that those ordinances permit sufficient height of those antennas and support structures so as to reasonably accommodate amateur radio communications by federally licensed amateur radio operators.

Restrictions imposed on such antennas and support structures by ordinances shall constitute the minimum practicable regulation necessary to accomplish the legitimate purposes of the governing body enacting that ordinance. For purposes of this section, it is presumed that any ordinance that prohibits or has the effect of prohibiting any antenna support structure that is 70 feet or less in height above ground level, exclusive of any antenna upon the structure, is unreasonable. No federally licensed amateur radio operator, applying for permission to install or modify an amateur radio antenna or amateur radio antenna structure, shall be required to pay an application fee that is in excess of that which may be assessed for residential variances generally, nor shall such applicant be assessed any amounts for legal, technical, or other consultation or advisory costs incurred by the reviewing agency in evaluating the application submitted.”

 I love my wife and I love NJ!