Code of Practice for RSGB VHF/UHF/SHF Contests

1. Obtain permission from the landowner or agent before using the site and check that this permission includes right of access. Portable stations should observe the Country Code.

2. Take all possible steps to ensure that the site is not going to be used by some other group or club. Check with the club and last year's results table to see if any group used the site last year. If it is going to be used by another group, come to an amicable agreement before the event. Groups are advised to select possible alternative sites.

3. All transmitters generate unwanted signals; it is the level of these signals that matters. In operation from a good site, levels of spurious radiation, which may be acceptable from a home station, may well be found to be excessive to nearby stations (25 miles away or more).

4. Similarly, all receivers are prone to have spurious responses or to generate spurious signals in the presence of one or more strong signals, even if the incoming signals are of good quality. Such spurious responses may mislead an operator into believing that the incoming signal is at fault, when in fact the fault lies in the receiver.

5. If at all possible, critically test both receiver and transmitter for these undesirable characteristics, preferably by air test with a near neighbour before the contest. In the case of transmitters, aim to keep all in-amateur band spurious radiation, including noise modulation, to the lowest possible level. Levels expected of big stations are of the order of -60dBc at 10kHz spacing, rising to -100dBc at 50kHz spacing. Similarly, every effort should be made to ensure that the receiver has adequate dynamic range.

6. Remember that contesters cannot claim exclusive use of any part of any band. Please respect other operators at all times by avoiding using, or causing interference to, frequencies set aside for other legitimate users. This applies whether the other use is prescribed by an official bandplan (e.g. the 144.300MHz SSB calling frequency on 2m), by recognised code of practice (e.g. the 50.100-50.130MHz DX window on 6m), or by common convention (eg the GB2RS news broadcasts on 144.250MHz). If asked to QSY because of interference to any such use, please do so quickly and courteously.

7. Above all, be friendly and polite at all times. Be helpful and inform stations apparently radiating unwanted signals at troublesome levels, having first checked your own receiver. Try the effect of turning the antenna or inserting attenuators in the feedline; if the level of spurious signal changes relative to the wanted signal, then non-linear effects are occurring in the receiver. Some synthesised equipment has excessive local oscillator phase-noise, which will manifest itself as an apparent splatter on strong signals, even if there is no overloading of the receiver front-end. Pre-amplifiers should always be switched out to avoid overload problems when checking transmissions. If you receive a complaint, perform tests to check for receiver overload and try reducing drive levels and switching out linear amplifiers to determine a cure. Monitor your own signal off-air if possible. Remember that many linear amplifiers may not be linear at high power levels under field conditions with poorly regulated power supplies. The effects of over-driving will be more severe if speech processing is used, so pay particular attention to drive level adjustment. If asked to close down by a Government Official or the site owner, do so at once and without objectionable behaviour.