 Auxiliary Items.
There are many auxiliary items available that the manufacturer will try to convince you that you need, but for the budget contester these can be trimmed down quite a lot, leaving only the items that really make a difference. In this section, I take a look at these and talk about what's really useful.
Morse Keyers.
Some people like to operate manually throughout the contest, just using the computer for logging, but for most, the repetitious work that the computer takes away from them, sending faultless CQs and exchanges time after time without getting tired means that they are quite happy to let it do the hard work whilst they concentrate their attention on the craft of contest operating. Therefore, the budget contester need not purchase a special morse keyer or high quality paddle though it is always important to have a standard key connected in parallel with the computer output, in case of problems or requests for QSY etc.
Voice Keyers.
These are quite in fashion these days, and after a long day at the microphone calling CQ, many would say they are a necessity if you value your vocal-cords. MFJ make an external unit, and there are also voice-keyer cards, such as the W9XT Voice Card that can be purchased to fit in a spare slot in the computer. Although the circuitry is fairly complex, chips are available that handle most of the storage and processing so a home construction project of this type is a possibility for a reasonably competent homebrewer. Circuits have been published in magazines and on the internet. An alternative to this digital solution might lie in a discarded reel-to-reel tape recorder. I'm sure many hams have one hiding at the bottom of the junk box that could be resurrected as a voice keyer if a small tape loop was rigged up. Only the capstan motor needs to be working, not the motors on the spools. Pop musicians used a similar device as a multi-head echo chamber, so maybe your local music store has an old one in the back of the workshop.
Speech Processors.
Audio speech compressors have been largely discredited and few are seen these days, new or secondhand. The RF speech processor, a device that converts your microphone output to RF, compresses the signal and then converts it back to audio for feeding into the transmitter's microphone socket is a device that is well worth having and will make a big difference to your readability as long as it is not over driven. There have been many occasions when my signal just didn't get through until I turned the processor on, and it is a device that I wouldn't like to be without in a phone contest, especially if the antennas are not quite up to KC1XX standard. Some of the modern transceivers have an RF speech processor already built in, but external add-ons are available, either new or secondhand.
Headsets.
There are some super headsets with boom microphones available these days, at prices to match, of course ! For the budget contester, these are rather out of reach, but alternatives are available. Headphones by themselves are cheaply obtained these days, due to the popularity of the Walkman. These lightweight headphones are comfortable to buy and have a good frequency response. Their low impedance will suit the majority of today's equipment, and an older receiver can be fitted with a step-down transformer or a simple series resistor. If you don't like the hiss from a headset with a HI-FI frequency response, experiment with series or parallel capacitors until its more to your liking.Sometimes, ex-military headsets turn up at rallys etc, and can be a bargain as they are usually of a high quality, though do check that they will be comfortable in a long contest. If the 'framework' is OK but the earpieces or microphone are faulty or of the wrong type, you can usually replace the inserts with those from an old ham-microphone or walkman headset if you don't mind a bit of fiddly soldering. Another idea: I have seen fairly cheap headsets with boom-microphones at my local computer store; they are designed to be plugged into a soundcard and may be worth investigating. I have found a website that shows how to build a preamp to use with one of these - click Here.
Loudspeakers.
Most ham-gear manufacturers sell a matching external 'communications-loudspeaker' to go with their transceivers, but there will be little difference in it from any other loudspeaker, apart from the matching case. A loudspeaker from an old TV or wireless set will do just as well, built into a small plywood cabinet. Alternatively, a ready mounted speaker might emerge from half of an old HI-FI or music centre; perhaps the dog put his foot through the other and now they are both being disposed of.
Microphones.
A good microphone from Shure or the other manufactuers can be pricey, so it pays to experiment with alternatives. The important thing is that the microphone you try is compatible with your transmitter - some require matching boxes, preamps or DC feeds. An old CB set might have a microphone that you can use, or as mentioned above, Internet headsets might do. An insert from a damaged case can be tried in a different one, or mounted on the end of a homemade boom or other support. A hands-free microphone is the best type for a contest operator, as it leaves you free to operate the radio and computer. A desk microphone generally gets in the way. Some people prefer to operate VOX in a contest, whilst others use a foot-switch for the PTT. I use a small switch set just under the main receiver tuning knob, where it is easily accessible.
Audio Filters.
The best type of filters to use are the narrow band IF filters in your receiver; good ones make a huge difference to contest operating, and their bandwidth should suit the mode in use. Buy the best IF filters you can afford - you won't regret it. Failing this, the alternative is to filter the audio after it leaves the receiver. Various types are available, fixed or tuneable; with varying bandwidths. Don't get one too narrow, as they have a tendency to 'ring'. There are various HomeBrew circuits published from time to time, and the external audio filter is well within the capabilities of most constructers. With the increasing complexity of integrated circuits, the external audio filter using DSP has emerged, and many speak highly of them, though I've have never tried one myself. Whichever one you like the look of, remember it will never be as effective as a good IF filter.
SWR meters.
Everyone needs one of these, to let you keep an eye on your transmitter output throughout the contest and warn you of any sudden problems, like a cow that has just tangled in the guy-rope and pulled your mast down. They are fairly cheap, and if accuracy is not important to you, an ex-CB will do. You could even build your own; its a fairly simple project. However, don't forget that a lot of transceivers already have one built in, so perhaps you don't need another one.
Monitor Scopes.
Nice to have. Useful, too. No, you don't really need one, though.
Ham Clocks.
There used to be a fashion for the 'Ham Clock', with various time zones on show etc. However these days its easy enough to find a large-digit LCD clock in your local discount store that will do very well, though do check its accuracy before contesting. If you are logging with a computer, as most of us do these days, you've got a clock on the screen anyway, so an external one isn't needed, though don't forget to calibrate it from time to time, and especially at the beginning of a contest. If you are lucky enough to have a computer that's only used for hamming, its best to leave the clock set to GMT (UTC) with daylight-saving turned off; otherwise you'll have to edit your contest log line by line !
External Attenuators.
This cheap accessory can make a big difference to a receiver that has poor big-signal handling characteristics, especially on a band with a lot of adjacent broadcast signals like 40m. They are easy enough to make from formulas in many of the handbooks, though don't forget it goes in your receiver input lead, not the shared transmitter feedline !
External Receive Preamps.
This is another useful accessory to a lower-quality receiver, especially on the higher HF bands. They are easy enough to make , a bit harder to buy these days (like the Q-Multiplier - what ever happened to those ?) and as with the attenuators, don't forget it goes in your receiver input lead, not the shared transmitter feedline !
Antenna Tuning Units.
Whether you need one of these, and what type it should be, depends on the type of antenna that you are using. If its a self-resonant type, such as dipole or yagi, you'll need nothing except coax between it and the transmitter, whereas others, such as long wire or vee-beam need tuning all of the time. They are very easy to make for yourself as long as you can get variable capacitors big enough to handle the power of your transmitter; these are generally picked up at rallys or surplus sales though some amateurs have made their own too - after all, a high power variable capacitor is simply a number of metal semi-circles meshing with another lot of the same. There's even a website with information; look at the bottom of ON4CEQ's Magnetic Loops page. ATU designs are available in many books, and everyone has their favourite; I have always favoured the 'Z-Match' circuit for ease of construction and use as unlike some, it doesn't require a variable inductor.
Antenna Switches.
A costly item to the budget contester when new; they don't depreciate much when secondhand either. You could make your own if you can find a surplus high-power switch at a rally; whatever you do, you shouldn't switch between antennas when the transmitter is operating anyway. Do you need one ? Well, if you have more than one aerial lead, I would say yes. Its suprising how much time it takes swapping over PL259s, and its easy to get similar-looking leads mixed up in the heat of a contest.
Antenna Analysers.
I haven't got one of these yet, but its my next intended purchase. With low power and equipment that's perhaps not at the latest forefront of technology, its important to get every last ounce of perfomance out of your antenna farm; the best way to do this, so I'm told, is with one of these gadgets. They save a lot of time by taking a signal source and analyser right to the antenna, saving all of those trips back to the shack. To quote EI7BA, 'If the antenna is tuned up according to the analyser, you know that its going to work back at the shack - unless your feedline's faulty, of course.'
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