The VHF/UHF field day at Mt Ginini, January 2009.

The scene inside the tent where the operating desk was located. Equipment from L-R is a THP 60w amplifier for 50/52 MHz, TS670S transceiver on 50/52 MHz, two KR400 rotator controllers, a Yaesu FT290R on top of the rotator controllers for the 2.4 GHz band via the remote transverter, Kenwood PS430 power supply, Icom IC910H on 144, 432 and 1296. On the floor is a GME 25 amp power supply, a dc powered drink cooler and a Bird 43 wattmeter. The station is run on 240v ac power from an alternator.

The 10 GHz station built by Dale VK1DSH. Powered by a battery charged by solar panel, this is a self contained portable station. The IF radio is an IC202. The dish is approx 30 cm diameter.

VK1DA Amateur Radio

Last updated: Feb 2010

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Blog articles

Part of this site is published as a weblog or blog.

Photo Gallery

View my photo gallery here. Included are

Summer 2009 VHF/UHF Field Day photos added May 09
photos from 2008 VHF/UHF events added Dec 08
some historical photos from the 1960s (high school years) , 70s (Club Secretary years) and 80s (various including Brunei and Singapore) added Dec 08

My gallery at Flickr.com also has photos of my amateur radio events and activities.

Books about Amateur Radio and Electronics

See a range of books about Amateur Radio, both technical and general, at Andrew's Book Store. You'll also find books about Electronics and other technologies there.

Recordings of VHF/UHF beacons while mobile

On a recent trip to Sydney I checked for the VK2RSY beacons on 28.262, 144.420 and 432.420 to see how far out I could hear them.

I was surprised to find I could hear the 28 MHz signal at Sutton Forest and within a few km the 144 MHz beacon was also clearly audible. The 432 MHz beacon was very weak at that point but in the next 20 km it became quite readable. It was interesting to compare the signal levels from these beacons over the next 100 km or so of my trip. The best signal strength from the 144 and 432 beacons was at the start of the downhill slope on the highway just after Mittagong, heading towards Sydney. At that point the 432 MHz beacon signal strength indicated S5, with the preamp ON.

On the way back home from Sydney I recorded the beacon signals and the files are available here, in both MP3 and AMR format. I used a Nokia mobile phone to record these signals - not the most elegant recording method but it's a start. If you have software to play or convert the AMR format, the AMR file format produces more compact files. I used Miksoft.com's converter to produce the MP3 versions.

Recording 1 in MP3 format 1.4 MB - 1 minute, mostly the 432 MHz signal but at about 15 seconds you hear the improvement in signal strength and quality when I switched over to the 144 MHz signal and then back to the 432 MHz signal a few seconds later. AMR format 42kB

Recording 2 in MP3 format 1.4MB - 1 minute - starts with the 432 MHz beacon and at about 20 seconds, I switched to the 144 Mhz signal and back again. AMR format 42 kB

I was struck by the apparent change in quality between these signals. When I was stationary, both signals sounded clean and pure. While mobile the 432 MHz signal showed considerable multipath and smear like a 10 GHz sigal with doppler or rain scatter. I am not sure exactly what caused that effect on this signal . Apart from the blur or smear of the signal there was also at times a second version of the signal on a slightly different frequency, which I assume was an aircraft reflection with doppler shift.

Field day log sheets

Here are some log sheets and summary sheets for use in the Australian VHF field days. Printed on your printer and with your ink! Click and save, or right-click and save as...

Log sheet suitable for use in the field in Excel 2000 format - download, change as you wish, print it out. I find about 40 contacts per page is practical for field use. If your handwriting requires more space, increase the spacing between lines. This format does not have a column for the band as it assumes you will write the band at the top of each page. If you want a continuous log with all bands together, add a band column back in before printing.
Log and summary sheet - spreadsheet template in Excel 2000 format, one worksheet per band and a summary sheet. Use during the contest if you wish, or enter the contacts after the contest. This spreadsheet is not protected so if you mess with the formulas you are on your own. As it's a template, opening it with Excel will create a new copy ready to be saved as a spreadsheet XLS file.

You don't have Excel? no problem, download and install Openoffice, its spreadsheet opens and saves Excel sheets and it is free. Included on the cover DVD of recent Australian Personal Computer (APC) and other magazines, or downloadable from www.openoffice.org.

Field Day Techniques and checklist

My field day techniques page provides some ideas and describes my approach to field operation on VHF/UHF bands. Also here is my field day checklist. Some things such as clothing vary depending on the time of year, but basically I aim to be self contained, have backup equipment in case of total failure, be adequately clothed, fed and sheltered during the field day and to enjoy myself. These notes may help you plan your own field day operations.

Radio Links

Links to sites relating to amateur radio, including national organisations, clubs, special interests such as digital modes, moonbounce, HF DX, slow scan TV, VHF/UHF/Microwave communication.

VK-VHF Mailing List

How to subscribe and use the VK-VHF mailing list.

Grid Squares

Maidenhead Grid Square locator codes are now in common usage around the world by most vhf/uhf operators and contest organisers. Make sure you place your Grid Locator on your QSL card and be ready to exchange grid locator codes with stations you contact.

If you don't know what they are or how to figure yours out, this article by Guy VK2KU explains it all really well.