The 2.4 GHz transverter has been completed and I used it in the vhf/uhf field day on the weekend of 15/16 November.
Construction began on Sunday 9 November with the first components soldered onto the sequencer board, finishing on Friday 14th November when I finally measured the transmitter output power.
The next day I was on Mt Ginini, with a 24 db gridpack dish (obtained from The RF Shop) attached to the transverter, receiving a big signal from Ted VK1BL at Mt Coree. I replied to his call and asked how he was hearing me. He replied immediately! This was my first contact on 2.4 GHz, made all the sweeter by the knowledge that the transverter was home made.
Together with some other “firsts” on this field day, it made for a very good weekend.
I have written up the details of the design and construction and submitted it as an article for AR magazine. The article was published in July 2009 and can be found in the AR archives here.
This week’s project is to prepare for next weekend’s VHF/UHF field day.
I plan to operate from a mountain southwest of Canberra, with equipment for 50, 144, 432, 1296, 2403 and 10368 MHz. The first four bands are bands I have used before but the last two are new for my station. The 2403 equipment will be a simple transverter driven by a FT290R radio on 144. The antenna for that band will be a grid type dish.
The 10368 MHz equipment has been borrowed from another local amateur. It is a transverter driven by an Icom IC202 on 144, the antenna is a dish. It all mounts on a tripod which readily allows azimuth and elevation adjustements.
On all bands the main mode used will be voice, using upper sideband. For some contacts with more distant stations, morse (CW) will be used as it is much easier to hear weak morse signals than weak voices.
The equipment was set up and taken down each day as I was not able to stay overnight. The morning temperature on Sunday was about 5 which was much warmer than it could have been. Some contacts into Sydney on 2m and 70cm, with an attempted contact on 23cm with Adrian VK2FZ. Contacts made around town on all bands and a visit from Ian VK1FOTO (later VK1IS), John VK1JST and Charles VK1CM. Power was from the GMC 950va alternator.
6m and rotator controller in the car
The IC706 on 6, the rotator controller, the power supply for the 910 on the floor and a genuine banana peel which was placed there deliberately to prove I had eaten something during the contest. True... Also my IC7QA hand held radio is in the glove box, I had used it to see if I could hear someone on 432, using AM mode to detect an SSB signal. Oh yes, note the morse key on top of the rotator controller. This was used for only one contact, with VK2FZ in Sydney on 1296 MHz. The front panel for the IC706 is mounted below the car radio where it is easy to operate while mobile. The radio itself is elsewhere.
Icom IC910H on VHF/UHF field day, June 2008
The IC910H was used on 144, 432 and 1296 MHz. Note the external speaker to the right - I find the speakers inbuilt to most radios are too small, offer poor frequency response and dynamics, can't be turned up when you want more volume (without terrible distortion), direct the sound upwards when you want it towards the operator, and so on. So I always use external speakers even on field day.
The roadside location at the top of Red Hill, Canberra, about 2 km south of Parliament House.
VHF and UHF antennas for winter field day contest
The antennas used were an 8 el yagi on 2m, 16 el on 70cm and 2 x 15 on 23cm. The guy ropes are at the 10ft mark on the steel telomast. My standard field antenna mast, as used over the last 20 years or so. Photo taken with flash at night.
VHF field day from the car. Red Hill Canberra
This temporary setup was sufficient for me to operate in the VHF field day on a mild winter's day in Canberra. The IC910H was placed onto a temporary shelf above the driver's console, with feedlines entering via the right rear door's window. The IC910H provided 144, 432 and 1296 MHz bands. The IC706 provided 50 MHz coverage and some occasional 146 MHz FM contacts via the mobile antennas. The rotator controller was placed on the central console and the log pages were balanced on the steering wheel. It worked.
The temp outside was around 4 to 5 degrees, so it was much more comfortable inside the car than it would have been outside. it was about 3 C the next morning, still quite mild for Canberra winter. I had been expecting temps about 5 to 8 degrees colder .
VHF Field day in the car
Another view of the operating position in the car. The passenger side would have been less congested but did not have the "equipment shelf" above the console.
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Amateur Radio, Computing and other activities of Andrew VK1DA/VK2UH