Ham Radio
Ham Radio is one of those tech hobbies that people either understand completely (i.e. they are a ham) or have no idea what the fascination is (i.e. the rest of the world). In years gone by ham radio was the only way of talking or communicating with people over great distance with no per minute charge. Some would say for no cost, but the cost of the equipment was sometimes significant. I was first licenced in 1993 as ZL3TDI (and I still have that callsign now that NZ has lifetime licencing at no cost) and at the time cellphones were very rare and few people used the internet. I was able to use my VHF handheld to access a phone patch that operated in Christchurch, and this let me place local calls. Funny thing was that people wondered why you’d want to make a call when out and about — now look at the prolific use of cellphones!
Emergency Communications is one area where ham radio still holds its own, and my introduction to this was through Branch 05 (Christchurch) AREC (Amateur Radio Emergency Communications). While I didn’t participate in any ‘real’ callouts, I spent a fair bit of time freezing my butt off at jetboat races where AREC provided communications. These races were run from the coast to the foothills, with spotters (like myself) relaying boat numbers and times from the riverbank to a nearby vehicle that had HF communications back to the race headquarters. This provided plenty of practise in message passing and reinforced the value of having a thermos of hot coffee at all times!
I now have the Australian callsign VK4TDI. Now that I have HF priviledges (with the removal of morse code requirements) I am working on HF as well as VHF and UHF. I’m yet to get a full HF antenna setup, so I am limited to using my Buddipole at home, as well as in the field (which is what it is designed for). A recent interest is APRS which is a radio based reporting system that is primarily used for position reports (using a GPS receiver), but can also be used for messaging. More details of my APRS activity are on my APRS Page.
My radio collection consists of a portable, two mobiles, four handhelds, plenty of antennae and some accessories. These are:
Portable
- Yaesu FT-817 all-mode HF, VHF and UHF. This has the bhi DSP fitted, which is absolutely fantastic. I’ve also fitted the Collins SSB filter, One Big Punch microphone compressor and the Kranker knob. I use the LDG Z-11pro antenna tuner because it is a smart auto-sensing tuner and doesn’t require any ‘smart’ connection from the FT-817. LDG have released the Z-817 tuner which would be my preference if I was starting again.
Mobiles
- Yaesu FT-1802 VHF FM rig. This an incredibly robust mobile rig that has big controls and is easy to drive. It is 2m only, FM only but it is cheap. There are no cooling fans and so it is nice and quiet, even at 50W. Bob Freeth’s (G4HFQ) FTB1802 makes programming the rig so much easier, and I recommend it. I made a modification to my VX-5R (see below) programming lead that connected the programming line to the CLONE pin on the FT1802′s mic jack. The Mic jack is a 6p6c RJ12, so make sure that any plugs you use have six contacts rather than the typical 4. This radio is currently sitting idle, but will be my APRS digipeater radio (silent & robust).
- Yaesu FT-8800 VHF/UHF FM rig. This was purchased to be installed in my VW Golf (see the detailed posting), but it proved too fiddly to be used easily. I use FTB8800 to program the radio, and again made a patch cable that let me use the ADMS programming lead from my VX-5R with the FT8800 (which is programmed through the mini-DIN 6 pin accessory port). This radio is now my main VHF/UHF rig for my radio room.
Handhelds
- Yaesu VX-5R 6m/2m/70cm FM. This was my first rig in Australia (since my Kenwood TH-77 died) and I purchased this second hand. It had a hard life with its previous owner and so doesn’t put out full power on the various bands. It is a reasonable shortwave receiver (AM only), but the front-end can’t cope with much signal, and so anything other than the stock antenna leads to overmodulation. I used to program this with ADMS-1E, but now use VX5 Commander.
- KYD TK-338 UHF handheld. This cheap Chinese handheld is functional, but not spectacular. It allows transmission and reception on the 70cm ham band, with receive capability of the 468MHz LEPS band and the 477MHz Citizen Band. Fortunately this radio uses the two pin Kenwood connector for accessories and so my old Kenwood speaker-mic works fine.
- Puxing PX-777 VHF handheld. I use this radio in my Track In The Box portable APRS tracker. Again, a cheap Chinese radio, but much higher quality. The buttons and switches work nicely, and you’d be hard pressed to know that the radio cost less than $100.
- Icom IC-92AD VHF/UHF D-Star/FM handheld. This was my Christmas present to myself, and it is a fantastic radio. D-Star is fairly limited in Brisbane with only the Springbrook repeater (VK4RWN) operating, but once The Knobby (VK4RBX) is up and running I should be able to operate handheld, instead of relying on the 2m outdoor antenna. The FM quality is very good too, and the interface is very easy to use. Icom’s RS92 programming software does make life easier when there are over 1000 channels available. The scanning features are better than the VX5 and so this is a good listening radio too. I wanted to buy the HM174 waterproof speaker-mic, but Icom Australia have decided not to import it. Therefore I had to buy the HM175GPS microphone with embedded GPS
This mic has much better audio than the one on the radio and the speaker is much more efficient. The cable is on the heavy side, but it gives the radio a ‘commercial’ feel rather than looking like a cheap toy (which the VX5 sometimes did).
Antennae
- Benelec 2m (Dick Smith D-4822) base. This beast is a single piece, fibreglass antenna that is 3.4m long and provides fantastic gain. DSE claimed 5dB (1/2 x 2), but it outperforms the Maldol.
- Maldol VT-320D 2m/70cm base. This is a two-part antenna, 3.2m long that claims gain of 6.5dBi on 2m (5/8 x 2) and 9.0dBi on 70cm (5/8 x 5). Quite deaf compared to the Benelec, but does provide 70cm coverage. The band tuning is not quite right for Australia, being optimised for 144-146MHz in Japan. Not currently installed, but will probably do fine for the local APRS digipeater.
- Comet SBB5 2m/70cm mobile. A nice antenna that is installed on my car, which is used for APRS tracking and occassional handheld use.
- Maldol HS702S 2m/70cm BNC whip. Provides far more gain than the ‘dummy loads’ normally supplied with handheld. This doesn’t get much use now that my handhelds all have SMA connectors.
- Diamond SRH999 6m/2m/70cm/23cm SMA whip. This gives a good boost to the VX-5R or IC-92AD when out and about. 6m and 23cm have never been used.
- Comet SMA501 2m/70cm stubby. A tiny short (45mm) SMA antenna that works nicely on the VX-5 for local work where I don’t want an antenna to snag. This works really well when cross-band repeating from my VX-5 through the FT-8800 to one of the more distant 2m repeaters that I use.
- Buddipole portable HF/6m/2m system. There’s a whole page devoted to this antenna, so head over there for the details.
Power Supply
- I use a range of sealed lead acid batteries (7Ah, 18Ah & 24Ah) and a large AGM battery (100Ah) to operate the radios with out mains power.
- I have a GME PSM1215 switching power supply that puts out 15A peak to run the FT8800, but recently I’ve used the large batteries to keep the noise down. For extended operation the power supply is great. The fan is current controlled and will spin up when a radio transmits, but the idle speed is a bit high and the noise is noticeable. The ‘dumb iron’ power supplies are quieter, but are much harder to move around the place.
Computer Interface
- The Tigertronics Signalink USB is my primary interface between my computers and radios. I’ve wired it up to use the defacto standard 6-pin mini-DIN accessory plug, and so it works with my FT-8800 and FT-817 radios.
- Sometimes just sitting a handheld next to the microphone on the laptop is all that I need to do to be able to decode audio.
This all keeps me out of trouble!
