After some years, discovering a mis-match in times on the clocks, two new ones were purchased.

Immediately there was <1-sec of difference between the two, but within human reaction-time, so not a problem.

After a short while some timings became suspect; at home during the week clocks were monitored against each other, a standard wrist-watch and computer-time:

Sure enough, one older clock jumped -2 seconds (at about ~17:00), then next forenoon was showing +10 seconds, so a +12 sec jump;

one of the newer clocks jumped -59 seconds overnight, then seemed gradually to gain +2 sec (between 18:00 and 23:00), returning to ±0 by the following forenoon.

National Physical Laboratories were contacted;   there is little confidence that R-C clocks will show continuous correct time.  The problem is that they can jump, and this significant jump is unpredictable (maybe during a race, before or after, or at night .... ).

post-script:  At an Open Meeting the competitors all recognised a start-time error of ~36 sec;  the Race-Officer was unaware of any error, save that competitors were strangely unprepared for the start.

That'd mean counting-down just about every second, since IF the clock were going to jump at some indeterminate time, it might do so at say, 3min:28sec, becoming 3min:21sec, and you might not have spotted that ???

Often, very reasonable count-downs hit 'key' points like every 30-sec, and during the last 30-sec every 5-sec, and during the last 5-sec every sec.   Problem is if there's a time-jump between key-points, or if the key points are too widely separated.

Notion of occasionally having a Cttee-boat, starting several races, with finishing conducted at a fixed line from a normal-use race-control office.

The idea of having 2 Reliable Clocks one afloat & one ashore seemed conveniently to obviate the need to use one stopwatch and coordinate times across the radio (before, during, after a starting sequence; nightmare!);  what was unexpected is that the Reliability of Radio-Controlled clocks is very questionable.

 

(Excuse me one second. The colours and variable size fonts have given me a headache.

 

 

 

OK, that's better.)

 

Very interesting. I didn't know that - most ROs I know use RC clocks.

I note with interest that the ISAF policies are to base timings on GPS time. But there are problems with that. http://gpsinformation.net/main/gpstime.htm" rel="nofollow - http://gpsinformation.net/main/gpstime.htm

Sorry if you've got a headache (He-He!) ..... clearly not enough time spent accustoming to rose-tinted specs or something ?

EXACTLY the Point;  this particular Club had, in their innocence, assumed through the marketing that RC Clocks only appeared on this Earth very shortly after the Big-Bang, or at least after Sliced-Bread !

What they do not tell you is that RC clocks have a mind of their own and can skip at will, usually by only a few seconds, but I now have evidence of full minutes [NPL.co.uk can confirm this].

Since SailBoat races are usually subject to human reaction for gauging start-time, finish-time or sighting a finish-line and transferring that to a timing, it is probably perfectly adequate within the envelope of controllable errors to use a wind-up grandfather clock (I bet some Cowes support boat somewhere has one of these on-board); ludicrous to expect help from a timing device to the nearest hundredth, or thousandth of a second, but what is controllable is Not to use a device that might be skippy; do Not use RC Clocks for timing particularly handicap races.

Yep, I recognise the GPS time issues also.

That's what you might have "Expected", in all innocence as said previously.

The spec. says that they'll correct automatically and if they don't receive a signal then they'll search at 02:00, or 03:00, or 04:00;  all our clocks are saying that they've got a good signal yet ...... ?

However that's not reflected in reality; (I did this 3-years ago but now again), over the last 3-days I've monitored clocks and assumed Google time to be my Reference, in which case one RC clock has +1sec during yesterday evening, then corrected itself overnight, and another RC clock has -59sec overnight from Sunday, then +60sec on overnight correction (but when ?), and during today has actually +1sec further and very gradually over 7-hours.

Last week a clock showed -10sec, then during late afternoon +2sec in front of Commodore's eyes;  his reaction was excitedly to ring-around saying that he wouldn't have believed it if he hadn't seen it with his own eyes !

Yes, there's been p-l-e-n-t-y of strange mixed fleet handicap timings (Couple of times per season, maybe? Not enough to really worry the majority, but significant enough.) and I've been banging-on about this for over 4-years now ;  I personally have very little confidence in Radio-Control clocks and now have my own empirical evidence  ...... heck last week in exasperation Mr Commodore himself took clocks home;  later one evening he could hardly contain himself in seeing-with-his-own-eyes a shift of +12sec happen, from a mismatch of -2seconds between two of the RC-clocks; he was quickly onto the phone .