The AHARS Technical Seminar 2010

By Christine Taylor VK5CTY

(As published in the November 2010 issue of "Amateur Radio")

The AHARS Technical Seminar was held at the Belair Community Hall on Sunday 19 September 2010. Before the door opened there was a queue of people waiting to come in. All together, 85 people attended (including four students from one of the TAFE colleges). All found something of particular interest.

The lunch and morning and afternoon teas were pronounced to be excellent and more than ample.

The lectures ranged from two by Drew Diamond VK3XU in which he spoke of some of the items that have appeared in AR from time to time and others that had not. The demonstration items he brought along were very good.

Phil Harman explained very clearly the principle of High Performance Software Defined Radio (HPSDR) and his talk was backed up by the working station set up by Hans Smit VK5YX.

Rob Gurr VK5RG gave a talk about early SSB when the amateurs were experimenting with this new medium and were building their own phase modulated equipment because there was no commercial manufacturer prepared to make radios that may represent just a passing phase - no pun intended.

Keith Gooley VK5OQ and lain Crawford VK5ZD demonstrated different systems used for transmitting and receiving on UHF and SHF. Several large dishes were assembled to be examined and some very small components (designed to operate on very short wavelengths) such as wave guides and mixers were passed
around to be studied.
Drew Diamond

The lecture ended with a two-way contact from inside the hall to a (very) mobile station out in the car park. The vehicle in the car park looked like an angry porcupine and could operate on everything from SHF to 160 metres.

To end the day Graham Dicker VK5ZFZ showed us a number of techniques for making very professional looking front panels for your home brew equipment.

As well as the HPSDR of Hans, there were several other items to be studied in the breaks such as antennas, amplifiers and other items of interest.

A commercial grid-pack style antenna
put to good use by amateurs on 2.4 GHz

A view inside one of Drew Diamond's
transmitters showing coils he winds

A 10 GHz receiver and horn antenna used
to receive the 'mobile' radio station
located outside the hall
The collection of tools that Rob VK5RG
keeps close at hand