Keeping directional WiFi antennae pointing at access point

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Thanks, I like the ideas of using the PC to control the device, steppers and windscreen wiper motors. I haven't interfaced a PC to the real world via ports since the Commodore PET although I did a fair bit with the early first and second generation microprocessors.

Where can I get information on the best way to interface hardware to the laptop - is there a website specialising in that? Also, which language would be best for me? I don't want to spend ages learning a new language for the sake of it so something intuitive and easy to learn would be good.

As for satellite dish control, I have looked into that in the past. Very small dishes are not very directional so the control could be achieved with a fluxgate but 800cm would be difficult and 1.3m out of the question. For satellite control you will probably need to take a measure of the signal. If you don't want to fiddle too much you could take off the dc from a 'satellite finder' - the loss of those things is not too bad and could be compensated for by an in-line amp (amp and satellite finder very cheap from Ebay in the UK). Sense is more difficult to obtain and that's the real problem as in a real situation you will be pitching and yawing, so your signal will be lost from time to time anyway.
 
Have a poke around i the site I mentioned above. It looks like a good start. For most you can probably use any language you like. I used to do a lot of that kind of stuff in pascal, but one of the many flavours of basic is likely to be just as good. To find that site I googled 'stepper motor controller'. But it looks like there is an amateur robot building community you could usefully tap into.
 
This interesting post has got me thinking.

On our Legend we have an emergency tiller that slots into the quadrant that turns the rudder. If I mount the Repeatit on top of that and turn on the autopilot then the rudder should try to correct the boats heading. Without water flowing over the rudder that won't do anything - but the rudder will return to the correct heading as the boat swings back round again. By adjusting the rudder gain and the response time this might work. We are going out to anchor soon and will try this.
 
Thanks, it looks good. I can't right now as am anchored in the Mar Menor in 20/25kts gusting, from 340 to 090, so sporadic WiFi - which got me going on the idea!
 
I don't think you'll ever get that going as the AP will continue to apply rudder (to its limit) until the head responds. Furthermore, you don't really want to put hours onto your AP for WiFi, I think?

How are you getting on with your Lifeline batteries and large inverters? Does the system do what you expected? Would you do the same again, or how would you do it differently? Maybe take this to a new thread if you have much to say?
 
Lots of hightech ideas here.

I wonder if there is a simpler solution - which might work a reasonable % of the time.

If you had something like a wind generator - could you clamp the repeatit to this and use this for the directional stability (assuming some wind of course) Would need to be manually setup in the first instance - but if the wind was constantish (or within the directional tolerance of the aerial) - it might work as the boat turned with say the tide.

I'm sure its far from perfect - but its definitley a lower tech solution.
 
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I don't think you'll ever get that going as the AP will continue to apply rudder (to its limit) until the head responds. Furthermore, you don't really want to put hours onto your AP for WiFi, I think?

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Just tried it in the marina and you get an off course error after 20 seconds!!!! I can change the setup to accept a 40 degree off course error before it alarms. This needs some playing with at anchor - but I expect your are right.

I wouldn't be worried about over using the Autopilot just for the wifi because it would only be for relatively short periods - compared with the hours it gets doing it proper job.

We have the amps to cope - and yes the Lifeline AGMs are working great - charging up very quickly with the 280 amp dc genny - and we are using the inverter to run the hot water and microwave and only run the genny when we are down to 70% of our 1050 Ah house bank.
 
Here in the Med tide and current are almost trivial most of the time. With wind alone one is swinging wildly. As I write, I am sheltering behind an island in Mar Menor and the wind is coming round both sides causing us to yaw over 100 degrees (+/-50 degrees). I think that it has to be an electrical solution.
 
Lemain,

We planning on buying one of these (RepeatIt) for this years "cruise" - Southwest England, Scillies and Ireland.

But we were planning to be at anchor most of the time.

Does this mean it is so directional that I am wasting my time ? Or does it just let you down in specific situations.

We are a 33 foot cat and usually bridle so don't swing badly but of course we are certainly not static.

I am not aware of omni directional WiFI kit. Does anyone know if one is made?
 
Most WiFi antennae are omnidirectional. All of those with stubby little black rods and the ubiquitous Belken USB are omni. People carry out mods such as putting tin cans behind them to make the antennae more directional hence increasing the gain in the required direction and - just as importantly - reducing the noise from other sectors. The Repeat-It is pretty directional but the overall gain is so high that it should work fine in most marinas. It is a pretty good compromise - if you can't get your Repeat It to work you are unlikely to be able to get a (legal) omni to work either. You can buy a high gain omni and/or high power amplifier but that is potentially (but not necessarily) antisocial and illegal.

I have our Repeat-It on the cabin roof next to a wooden box for stability, on a anti-slip mat, and tie it on when the wind picks up, then move it round as we swing. I am having to do that today and that is how this post got to you.
 
Lemain,

Thanks for the info.

So someting like Omni antenna would be "better" (from a purely selfish point of view) but possibly illegal and antisocial ? (they do a 15DBi version on the same website but that link describes a "kit")

I just want to buy the best reasonably priced bit of kit that will work when we are mostly at anchor this year and my practical experience of this is limited to domestic wifi. I don't want to upset anyone so would appreciate advice as to go down the Repeatit route or one of these Omni versions.
 
What we have done when theres a good wi-fi signal is to take a repeater ashore with battery & sometimes solar panel set up the yagi in that case and re transmit with a non directional antena

Most anchorages have bits that are only accssesable by dingy. Depends how long your staying & if its not easier to sit in a comfortable cafè in the shade with a garaf of cool white local wine a crisp salad & crusty bread.
 
For accessing WiFi whilst at anchor using a 'high-gain' antenna you can do no better than using a 'Bow-Tie' array, stacked and bayed.

This will give you all the gain you require without the severe directional properties of a Yagi. You might also like to look at using an 'Alford Slot' antenna.

The high-gain Yagi is really only of use for a fixed installation or possibly if you drop out a kedge from the stern
 
Maplin sell a Velleman USB Interface Board kit which should allow you to control relays etc easily. Either my web or theirs is very slow right now so I couldn't get a link to it.
 
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