AUSTRALIAN Amateur Radio Station
VK4ADC rotating GIF
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Callsign : VK4ADC
Location : Brisbane, Australia
Locator code : QG62mj
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Home
GoogleSearch VK4ADC.COM
Site Feedback Form
Background
VK4ADC Log Searches
VKLogger
(handy link)
MUF page
Radio Propagation References
Web Links
Technical
/Construction
References:
HF Antennas : Squid Pole Mounting for Field Days Trap dipole for WARC bands & Diamond W-8010 antenna Field Day Antenna Ideas HF Helical Whip Calculator (for Windows) Tuning coax traps Trap-style Inverted-V for 10 to 80 metres
Info : ICOM 720A Rx Preamp IC-720A handbook pages 27MHz CB to 50MHz conversion Producing PCBs using positive resist board Toroidal Baluns Coaxial Cable Comparisons dBm to uV and dBuV lookup table
VHF Marine frequencies
Wire Gauges with resistance values for copper conductors Copper Wire Sizes and Data CB Channels
Radio quiet notebook computers
SPECIAL ITEM : Caveat Emptor warning about Ebay Seller "radio-mart" of Kentucky, USA.
VHF/UHF+ Projects : 1296MHz / 23cm Transverter
VHF PLL Synthesiser project
432MHz/ 70cm Transverter
Motorola MHW1815 / 1915 power amp mods for 1296
Software : GridLocW Lat/Long to Maidenhead converter for Windows
Using VKCL Software with multiple Icom Transceivers on a common CIV bus.
Operating:
VK VHF/UHF Field Day Reports : Summer 2009 2010 Winter 2009 2010 Spring 2009 & Field Day Ideas
John Moyle Field Day Report : 2009 2010

 

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Doug VK4ADC

Doug Hunter
VK4ADC

I held an amateur licence from 1967 as VK4ZDC and was active on 6 metres (52 - 54 MHz) from that time, adding 2 metres AM then FM and finally 70cm SSB to the operating bands. After upgrading to a full  licence in 1976 and taking the call VK4ADC, I operated mainly 20 metres SSB with some 6, 15, 40 and 80 metres as well as promoting RTTY in South East Queensland. The on-air activity declined with change of jobs in the early 1980's but the construction of projects including RTTY & voice repeaters, packet digipeaters etc continued. I returned to somewhat higher activity levels after September 1999 when business was a little slow and I had time to fix the old gear - bit by bit.  

Since then, the radio gear has been updated, repaired, re-calibrated and new ideas incorporated.  I have previously done some development towards a fox hunt receiver for 2 metres, built a new 6 metre transverter and modified an old 27MHz CB linear to 50MHz to provide a bit more grunt. The technical side has stayed with me and I continue to experiment with antennas and in-shack hardware and software development. The SMD component movement has caught up with me in the creation of new projects at 70cm and 23cm using these techniques even though I have a reasonably large stockpile of standard size components (eg 1/4 watt resistors, ceramic disc capacitors...). Fortunately the hands don't shake too much and the eyes are still working ok, the brain is still working well too...

I originally trained as a Radio Technician in the old Department of Civil Aviation (DCA) at Brisbane airport and then worked as a Radio Technical Officer in the comms, RADAR, test equipment pool and training school areas before joining the Postal and Telecommunications ("P&T") back in 1978 as a Technical Officer doing broadcasting, TV and radiocomm interference work (i.e. a "Radio Inspector"). My time in P&T / DOC / DOTC / SMA (now named the ACMA) saw me working in many areas - and gaining experiences - in many aspects of radio and communications. I left that organisation during one of their staffing down-sizes (my choice, not theirs !) and moved across into the computer service and sales industry. I started a move back into the radio industry back in late 2003, but this time with more of a retail leaning - though I was still involved in many "technicalities", plus designing and building antennas etc.. but wound that up in mid 2007. Now I am "nominally" retired from the workforce but still keeping pretty busy with domestic, some AR and recreational activities, plus a little paid casual work.

Back to amateur activities : In Sept 2000, I built up a new 50MHz yagi using the WA7RAI QY4 software as a design base - 6 elements on a 6.5m boom.  Tests against a standard 1/2 wave dipole proved a 11 to 12 dBd forward gain and a front/back of 29dB at 50.0 Mhz, VSWR of 1.05:1, basically the same as the design criteria. . While on the subject of yagis, Ron VK4KLC and I recently did some polar pattern measurements of his 5 element 6 metre beam. He transmitted about 8 watts carrier while rotating the array while I noted the received signal levels in dBm. The resulting pattern was almost identical to that created by WA7RAI 's QY4 software - front to back and side values were within a dB or so of each other.    Many others throughout the world have copied the design and I still occasionally receive an email from yet another happy builder.

March 2000 saw my operation in the CQ WW WPX Phone contest with about 550 contacts. I used the CT626 logging software and was about to email it off and noted that the points scoring was in error. It appears that this version is based on USA-based stations and doesn't cater for other countries. Because I don't participate much in contests anymore, I don't really want to go out and buy a later version of CT just for contests. I have found that EasyLog 4.5 is a good general purpose logging program but runs under Windows and really needs the speed of a DOS program under contest conditions. I don't really HF contest much any more even though I have the equipment and usually opportunity.

Current equipment in the shack includes the Icom IC-7400 transceiver coupled to an old Yaesu FL-2100B linear (who says I play 'brand favourites !'). I still have an old Icom IC-720 that I can utilise in a standby position (with a 2nd one on the shelf) plus an old Yaesu FT-DX560 (from when I was first licensed for HF back in 1976) in storage under the benchtop. As time permits, I hope to spend more time checking these older items out and making them completely functional to specifications again.

With initial details from Gary VK4AR, I modified a 27MHz CB transceiver with PLL02 synthesiser (Cybernet series) up to 50MHz a few years ago so that I could take it mobile / portable / on field days. With some variations from Gary's original details, it's up and running producing about 10 watts SSB. When 6 metres is in an active phase, it sits connected to the 50MHz J-Pole (as described elsewhere on this web site), left on 50.110 with the squelch just set. Even if I don't hear the weaker DX, I certainly hear the locals working it so am alerted to run into the shack and get on the air with the IC-7400 on the yagi ! That modified CB gear doesn't move out of the shack for field days nowadays and just stays monitoring 50.110 USB.

I am seldom found on air however I do try to read the VK1WIA news each week on the web if I can't find the time to listen to it. I do keep myself up to date with most happenings about amateur radio - something that I have tried to do for most of the last 40-odd years.

More-so since becoming a WIA Assessor, I have encouraged others to join in this fine hobby - and appropriately licensed - by running some theory coaching courses and practical activities during 2007. There hasn't been much call on me since those but who knows what this next year will bring !

 

CURRENT ACTIVITIES (as at 2010) :

  • Trying to monitor 50.110 when in the vicinity of the workshop/shack and keeping an ear out for DX calls but doing some tuning around particularly in the 50 - 50.1 beacon segment &  also monitoring the simplex 145.650 MHz local (Brisbane) 6 metre liason net frequency. This gear runs from a timer from around 7AM to 9PM, 7 days a week.

  • We run cable modem router access to the Internet so have it connected to a home-LAN which also connects to the PC in the radio shack. I can now check the VKLOGGER activity (and other DX pages) from there on the rare opportunities I really operate from home. (eg RD Contest)

  • Activating my callsign in as many field days as I can manage: eg VK VHF/UHF Field Days.. Reports available from the menu at top.
  • Doing a bit of work in the shack : a 23cm & 70cm transverters, PLL synthesiser development, 23cm yagi antenna, GPSDO... still writing software like GridLocWM and small local utilities, and doing some field day operations. Laying out PCBs for my projects like my PICAXE transverter sequencer, audio frequency interface...

  • See the menu listing at top of page for specific project & activity details.

 

 

Any feedback would be appreciated : Feedback Form

Last edit : 01-Mar-2010