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Syllabus Sections:- Working Mobile and portable 8F5 52 Understand that operating when mobile or maritime mobile can introduce new hazards i.e. insecure equipment, long/flexible antennas, accidental shorts to earth, lack of attention to driving. page 15 under heading of Safety in vehicles so take a good look here.This gives a good read for things to consider such as insecure equipment, long/flexible antennas, accidental shorts to earth, lack of attention to driving. ------------------------------------------------------------- 8F5 52 continued Recall the additional safety precautions that should be taken whilst operating mobile and / or maritime mobile i.e. secure equipment, cable routing / protection, correct fusing, use of hands free equipment, attention to good radio housekeeping. When installing all equipment to be used in a vehicle or on a vessel you must ensure that :-
It is a grey area as to whether a radio amateur can be prosecuted solely for using a hand held microphone whilst they are driving but if they are driving in an unsafe way then prosecution is almost certainly the likely result. It is thus strongly recommended to use a remote switched microphone so that operation is "HANDS FREE" However reading Rule 149 of the HIGHWAY CODE it says:- "You MUST exercise proper control of your vehicle at all times. You MUST NOT use a hand-held mobile phone, or similar device, when driving except to call 999 or 112 in a genuine emergency when it is unsafe or impractical to stop. Never use a hand-held microphone when driving. It is thus considered to be illegal to use a hand held mic whilst driving but it may is still open to interpretation. There is a significant change in the guidance section which affects the Advanced examination and the . The advice in MPT1362 [the code the RSGB publications are based on] and all copies of Advance up to and including the 2009 reprint was to connect the transceiver directly to the vehicle battery with appropriate fuses in both the positive and negative leads. This does not agree with accepted commercial practise. The recommendation is now to connect the negative return from the rig to a new point on the body shell, very close to the connection point for the battery strap - but specifically NOT sharing the same bolt as the battery strap because that is a likely failure point. A one-wire system would be very bad EMC practice. The negative return via the body shell creates a huge pickup loop, parts of which are also carrying other return currents from the car's own electrical systems - an open invitation to RF interference, both from the car and to it. To minimise the size of any pickup loop, it would be good EMC practice to use the two-wire DC supply with common mode chokes at both ends (there is often one inside the rig) and avoid connecting the rig to the car body in any other way. If an additional connection between the antenna base and the car body is not needed, then don't make one; it it's unavoidable (e.g. for HF mobile) then make another common mode choke on the coax cable. From where the negative wire terminates on the body shell close to the battery, keep the single red wire taped close to the battery earthing strap on its way up to the positive terminal post; once again you're aiming to minimise the size of any open pickup loop.
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