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There are several choices when it comes to procuring your first HF transceiver. This article provides guidance to help you make the right decision.

Buy new

New HF amateur rigs start from under $1500. While these prices may seem high,.amateur transcveiver prices have fallen sharply relative to real wages since the 1960s. When buying new, you also get the manufacturer's warranty and a better availability of optional accessories and spare parts. For details of new rigs, see the advertisements and reviews in magazines such as Amateur Radio.

You will notice significant price differences between new and secondhand HF rigs. When choosing a rig, consider bands and modes you may wish to use in the future. A $400 used transceiver may appear cheap, but will not have much of the following:

• 160 metres
• 30, 17, 12 metres
• AM and FM modes
• Digital frequency display
• Dual VFOs (required for much DXing and 10 metre FM repeater operation)
• AM and/or FM facilities
• General coverage receiver
• Narrow CW filter
• Inbuilt antenna tuning unit
• Digital signal processing

A Foundation Licensee needs none of these frills to make contacts, but they are nice to have later on. Even if you just need several, a basic new transceiver with all or most of them included (such as a Yaesu FT-817 or Icom 703) starts to look a better proposition. You also get the benefit of the supplier's warranty (2 years typical) and the better availability of optional accessories as mentioned above. Don't fall in to the trap of buying an older cheaper second hand rig thinking that you'll get the extras later - some accessories are much harder to find on the secondhand market than the transceivers themselves.
Similar comments apply for Standard and Advanced Licensees, except with their higher power limits there is a wider range of equipment to choose from. A popular no-nonsense 100 watt HF-only transceiver is the Icom 718. In contrast the Yaesu FT-847 or Kenwood TS-2000 appeal to those who want 'all bands in the one box'.
Apart from the top range home station transceivers (eg FT-1000 MK5), most new equipment runs off 13.8 volts DC. Home operation with these rigs require a power supply that can deliver at least 20 amps continuous. Suitable supplies are available new, second hand or in kit form. If you plan on buying a 100 watt rig, you should obtain a 20 amp unit. Any supply you buy or build should be regulated and include over voltage and over current protection. The Dick Smith D3800 is an example of a high-current supply suitable for any 100 watt solid state transceiver. This reasonably priced supply (under $300) includes voltage and current metering which is very useful.

Buy secondhand

A basic used rig can be picked up for between about $300 and $500. Generally older gear is the cheapest. If buying second hand, avoid the older all valve transceivers; these rigs may be over 30 years old and replacement valves, transformers and high voltage components may be hard to come by. As well, they are not as sensitive as more modern rigs, particularly on 10 and 15 metres. Portable and mobile operation with valve transceivers is much more difficult than with newer equipment.

Transceivers that are solid state except for the finals are a better proposition, but again they may not include all HF amateur bands. Examples include the Yaesu FT101 series and the Kenwood TS520/530/820/830 series. These can perform well for home station operation, but are too bulky for mobile and portable operating. Final valves for them are becoming harder to obtain and more expensive. You may be lucky and buy a rig that gives you twenty years service with the one set of finals, on the other hand you may not. If buying a set with valve finals, it is probably an advantage to buy one where the seller is offering one or more set of spare finals along with the transceiver.

For about 20 years all HF tranceivers from the major manufacturers put out around 100 watts. In recent years the growth of QRP, portable operation, and more recently the Foundation Licence encouraged manufacturers to make lower power equipment.
Going back, many lower powered sets were imported into Australia during the late 1970s/early 1980s when the old Novice licence permitted only 30 watts on SSB. Examples include the Yaesu FT-7, FT-77S and the Kenwood TS-120V. Though these sets do not cover all bands available to Advanced licensees, they make good starter rigs for the Foundation Licensee on a budget.
Possible bugs include dry joints, bad earthing, erratic internal sockets, display problems and frequency drift so test before buying. Expect to pay $200-350 for these older rigs.

Second hand gear is available from some amateur radio dealers or privately. Note that used rigs bought from a dealer may have a short warranty, whereas if you buy from an individual, you’re on your own if something goes wrong. When buying a rig privately, see it operating and insist on receiving the manual for it.

You can find out about equipment being offered for sale in your area by scanning the classified advertisements in both of Australia's amateur magazines, or listening to weekly broadcasts in some states. Many of these include 'buy and sell' or 'Disposals' segments. If there is no suitable equipment advertised, try putting an 'Equipment Wanted' notice in one of the magazines, on the club notice board or the VKHAM website.

Another place from which you can obtain used equipment is at amateur radio hamfests and junk sales. Details of these are normally given in the weekly broadcast and the amateur magazines. Radio clubs are good places to start when looking for used equipment. It is quite likely that at least one member will have gear for sale, and you will not need to travel far to collect the rig. You may even know the seller and the history of the particular piece of equipment being offered for sale. As well, if your club has its own station, you may be able to use it to test equipment that you are considering purchasing. Club members are also valuable sources of information on new equipment that you may be considering purchasing.

Convert equipment to the amateur bands (Standard & Advanced licensees only)

Another option is to convert a commercial Royal Flying Doctor or similar SSB transceiver to the amateur bands. These radios deliver good performance, are rugged and are great for portable and mobile operation, especially if you want coverage of only a single band, such as 80 metres. However, converting these radios has many pitfalls for the newcomer. These include:

• Price - second-hand RFDS-type transceivers can be much more expensive than a brand new fully-featured HF amateur transceiver.
• Availability of information - Unless you are an experienced amateur, you will need a technical manual to do conversions. This may not always be easy or cheap to obtain.
• Correct sideband - Some sets transmit on upper sideband only. This severely limits their usefulness on 160, 80 and 40 metres where 99% of SSB activity is lower sideband.  Also older rigs do AM only.
• Crystal control - The older sets that are available cheaply are crystal-controlled. However frequency agility is essential for amateur operation. A variable frequency oscillator (VFO) can be built in to some transcievers, but this is not a task for the raw beginner.

Unless you can get a set for a good price (less than $100), and can work under guidance of a more experienced amateur, I would suggest giving these transceivers a miss and buying or building instead.

Build your own (Standard & Advanced Licensees only)

Introduction

One of the unique aspects of amateur radio is being allowed to build your own transmitting equipment. Though it is unrealistic for the newcomer to be able to build their own multiband HF transceiver, building simple single band direct conversion receivers and low powered (QRP) transmitters is not unreasonable.

If you are on a very limited budget, building your own is the cheapest way to get on the air - an eighty metre Morse Code (CW) transmitter capable of covering distances of up to several hundred kilometres or more costs less than $30 to construct if all new components are used. Voice transmitters are a little more complicated to build and adjust, but can be rewarding projects.

The basic components for homebrew transceivers can be obtained from suppliers such as Jaycar and Dick Smith. However you will need to obtain more specialised parts such as variable capacitors, dial drives, toriods, crystals, RF transistors and ICs elsewhere. These can be found at amateur hamfests and junk sales or purchased by mail from the CW Operators' QRP Club. Some Australian and overseas companies put out transmitter, transceiver and receiver kits from time to time. If you can get one, a kit is a good idea for the constructor just starting out as there are no esoteric parts to seek. The main disadvantage of kits is that they are harder to customise to your requirements, especially if they are constructed on printed circuit boards.

Choosing a design

What type of homebrew transmitter should you start with? Sure, it's very easy to build a simple 80 metre Morse Code rig. Just one or two transistors and a 3.58 MHz TV colourburst crystal, and you're on the air. But will the rig sound OK? Will you get contacts? Or will the rig lead you to give up amateur radio because you are not getting responses to your CQ calls?

Gateway to Amateur Radio is about practical amateur radio. Radio that works. Radio that's fun. And to get the most enjoyment from your hobby, you need to know something about the capability of your equipment so that you don't expect too much and become disappointed when your hopes do not materialise.

That's why you have to be selective about the type of transmitting equipment you build. Firstly it must be fairly simple and not require too many hard to get parts. Secondly, it must be put out enough power to be heard on the air. Thirdly, it should be frequency agile over at least a segment of the band.

Power

What is sufficient power? Though this depends on the distances you wish to work, I would say that an inexperienced amateur aiming to make regular contacts with powers of less than one or two watts on 80 metres is going to be disappointed. Sure those milliwatt rigs you see described in foreign magazines do work, but remember that Europe and the USA have far more amateurs per square kilometre than we have in Australia. As it's so easy to build one or two watt transmitters that there is little sense in settling for less unless you specifically want to do experiments in milliwatt communications. I would recommend powers of 1-2 watts as a practical minimum assuming you are using a reasonably efficient antenna (eg a full-sized dipole on 80 metres). Though there will be times when more power than this will be required (eg when static is bad), you should be rewarded by reasonably frequent contacts up to several hundred kilometres, and the occasional two or three thousand kilometre contact with 1-2 watts.

Frequency agility

Then there's frequency agility - being able to move around the band, rather than being stuck on a single frequency. Most home brew transmitters are crystal-controlled. Most of them also sit on the shelf gathering dust and are seldom used. Why? Being locked on one frequency severely hampers your operating success. You could be calling CQ, but not be getting any replies. Then 5 kHz up the band, you hear another station also calling CQ. If you were frequency agile, you could move to the other station's frequency and most likely obtain a contact. Instead, you remain on your frequency, hoping that the other station will not get a reply, stop calling, tune around and eventually find you. A lot of people build simple rigs, have one or two contacts, and do not use them again for this reason.

The disadvantages of crystal control are greatest with low powered (QRP) equipment. Unless someone happens to start calling on 'your' frequency, the only way to get contacts is to call CQ yourself. As many people tend to reply to CQs from stronger stations only, your chances of getting a reply are reduced if your signal is weaker. A much more successful way of getting contacts is to reply to CQ calls from other stations (you know that at someone is at least listening for your call), or 'tail-end' contacts that are concluding. Both of these techniques are only possible if you can move frequency. And, if there is not much activity around, and you do want to call CQ, your chances are better if you can make the call on a clear frequency. The probability of this is of course much greater if you are able to vary your own transmitting frequency.

Another aspect of crystal control is that your crystal may not be in the most active part of the band. For example, 3.58 MHz TV colourburst crystals are conveniently in the middle of a busy part of 80 metres. However, most CW activity is below 3.550 MHz. Operators seeking CW contacts will not be tuning across 3.58 MHz. So, the chances of getting a response are reduced as you are not calling where most of your potential contacts will be listening. Of course, if you're on voice, 3.58 MHz is a good frequency on which to call. However, frequency agility is desirable for reasons mentioned previously.

Mode

If you are building a voice rig, should you choose AM, double sideband suppressed carrier (DSB) or SSB? Though some newcomers have successfully built SSB transceivers, an SSB rig is a challenging project for the average constructor. So, the choices boil down to AM and DSB. AM was used prior to the advent of SSB, and still has a small following on some HF bands. However, many SSB rigs do not have AM and it may not always be easy to resolve a weak AM signal on an SSB transceiver. Because AM signals include a carrier that does not contribute to the intelligibility of the signal, AM is less efficient than SSB, and more transmitting power is required to make oneself heard. DSB has an equivalent bandwidth to AM, but has no carrier. Thus it is a more efficient mode. As well, DSB is fully compatible with modern SSB equipment, and unless you tell them, many SSB stations will not know that you are using DSB. The combination of a direct conversion receiver and DSB transmitter is highly recommended for the Standard or Advanced licensee wanting to build an HF voice station, and because of the similarity of DSB and SSB, DSB transmitters can later be upgraded to SSB by adding extra circuitry. Such rigs are particularly effective on eighty metres. However, AM still has its uses. The speech quality of AM is generally better than DSB or SSB. Where you have a small group interested in local contacts only (such as within a country town or small city), a homebrew AM rig would be a fun project, particularly on ten metres where there is plenty of band space. Ranges of up to about 5km can be achieved with powers of under a watt.

VK3YE's minimum standards for homebrew rigs

Taking into account the above observations based on years of practical experience, I am now in a position to lay down some minimum standards for practical homebrew rigs. These are:-

• Power output at least 1-2 watts
• At least some degree of frequency agility in a popular part of the band
• CW and/or DSB operation.

If you see any design or kit that does not meet the above, you should have second thought about building it, even if it is cheap and simple to build. Don't laugh - kits of rigs that would be almost unusable on the air have been sold in the past in Australia. In my view, the presence of such kits does practical amateur radio no good at all in that they raise expectations and then fail to deliver.

Meeting VK3YE's minimum standards for homebrew rigs

1. Power output

Look for a design with a reasonable power output transistor. A BFY51, 2N3053, 2N3866 or 2N4427 in the transmit final stage should have an output close to 1 watt. 2N3553, BD139, IRF510 or IRF511s are all capable of power outputs between 2 and 4 watts. Two lower power transistors can be wired in parallel (with suitable emitter resistors) to produce more output. A 2N2222 or BC548 as the final amplifier is a sure sign that the rig is nowhere near powerful enough.

2. Frequency agility

A free-running VFO or synthesised VFO can provide full band coverage, but can be difficult for the beginner to get going properly. It is not always easy to obtain good frequency stability in a free-running VFO on the higher HF bands, and synthesisers tend to be somewhat complex to build. Nevertheless, a free-running VFO is a good choice for an 80 metre rig provided that care is exercised in its construction. Cheap 3.58 MHz ceramic resonators are also good for use on 80 metres - stability is acceptable, and the pulling range can be as much as 100 kHz, neatly covering a useful section of 80 metres. Ceramic resonators are excellent for 80m CW or DSB direct conversion receiver and transmitter projects. Quartz crystals are not recommended on 80 metres as they cannot be shifted very far in frequency. However, at 7 MHz and above, crystal oscillators (VXOs) can be pulled to provide worthwhile coverage of frequencies immediately below the crystal's nominal frequency. Ranges of 5 to 30 kilohertz can be achieved, depending on the crystal type and the operating frequency. VXOs particularly useful for CW/DSB equipment on 40, 30, 20, 17 and 15 metres.

3. Mode

DSB transmitters require a balanced modulator stage to null out the carrier signal. Devices such as the NE602 (also used in direct conversion receivers) can be used. Many older published designs use other ICs (CA3028 and MC1496) or two or four diode balanced mixers). Like in an SSB rig, power amplifiers used in DSB rigs have to be linear. This means that a power amplifier circuit used in a CW transmitter is normally unsuitable for DSB unless its operation is made linear.