Matt's GPS thread...


Senior member
Mar 12, 2004
Boat make
Humber Ocean Offshore
We left off somewhere about...... me saying that I thought, for speed calculation purposes, the gps software would discard the spurious fixes. There were posts after this but the site crashed before I got to read them.

Over to you, Matt.
Yes, but if it's averaging then the fix that indicated the +5mph would be part of the averaging. Eg. say it's averaging over 10 fixes, if 9 of them are good then that one will have a limited effect.
Do you know whether displayed fixes are averaged?
Matt said:
"spurious peak readings"

I can see that phrase getting some use here on boatmad! (along with "Searay Speedo".
It wasn't deliberate, just forgot to toggle it from 'OFF' in the Tech Q&A forum, rest were done;)
boat speeds

what is the best way to get an avarage speed then ?:brain:
A Gaffrig CG, or Windermere week
gaffrig cg

what does CG stand for
Gaffrig Competition Gauge.

Here's one I prepared earlier:


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Mathmatical modelling thread.

Matt said:
You'd assume there's some filtering wouldn't you, but at 65mph, an extra 5mph might be below the rejection threshold

I think You'd have to add 5 to every sample to continuosly to get the average up by 5.

There could be errors on the negative side too.

You could end up with a reduced speed if the system shifted your position the other way.

The M/Boat mags did a similar position trial.

Your URL sir...


MR sad git here, still had it printed out beside the PC.
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JK's a very bad boy! (anyone who looked at this thread earlier today will know what I'm talking about!


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Matt said:
Phew! Thought you'd got all JK on me.
Matt, you're in IT apparently, so you should understand why it's not sensible to deliberately leave a gaping security hole in the forums. I would have though that JF has had enough aggro with BoatMad recently without asking for more :lol:lol:

It's not fair when an IT expert picks on a poor Marine engineer, who's already out of his depth! this is in my black book Mr K!


'Humiliated of Shepperton.'
I've turned off 'HTML' in posts on all forums exept 'Torkin bollix' which I'll do later once everyone's seen Missus's smilie links.

Joking apart, thanks for the wake-up call John.;)
Calm down everybody! no need for upset.
We'll just suck it and see.

jon fuller said:
I've turned off 'HTML' in posts on all forums exept 'Torkin bollix' which I'll do later once everyone's seen Missus's smilie links.
These don't actually need HTML as vB code will do the job just as well!
Matt said:
I resent your implication that I would knowingly expose boatmad to undue risk. I can't be bothered to argue the toss so lets call it quits. It's Jons forum and if I post I'll follow his rules.
Fair enough! No offence meant :D

Oh No...

I'd just trained myself up in putting them on via HTML...

I hope it's not going to be complicated !!!!

However security is important and input from all you IT eggsperts is welcome...(apart from Richard B's wevver forecasts!!!)

Can someone explain why HTML is an 'issue' ...???

Is it that dangerous?

(A yes or a 'nayMissus' will not do

:laugh: :laugh: laugh:

I need dot-to-dot explanations!!!)


The Wazzok pin in the smiley engine right ... it could, if you're not careful endup thinking outside of the box and potentially allow the hetrogenoius and homologated systems to holistally approach a scope creep of the model, in the heirarchically openended object orientated topolgy of the seven layer pre emptive mutli tasking knitting pattern forwarding deamon.

Yes ...I think thats it

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