rudder servo recommendation ?

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awallin
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rudder servo recommendation ?

Post by awallin » 25 Aug 2006, 07:23

Hi All,

I'll be buying radio components for a new boat in the near future. I've always used plain standard Futaba servos for the rudder. This time I'm thinking of getting something slightly better.

Could anyone recommend something from e.g. the Hitec line of digital servos ?
A little more speed than a standard servo can't hurt.
More torque is probably not needed ?

It should have the physical dimensions of a standard servo so that the mounting hole in my boat will fit a standard servo (in case of an emergency switch needed at a regatta)

thanks,

Anders

Chairman
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Post by Chairman » 28 Aug 2006, 00:32

Hi Anders,
like you I have always used cheep standart servos and any sign of a problem I just replace them. Baisclly I treat them as a consumiable. At the last RM Championship I used a brand new digital servo and on 4 ocassions had it lock up freezing the radio etc. later I found out the 36mg radio I was using was shared in the UK with some car alarms. At the time it was a mistory becuse after turning everything off the problem disapeared. A real problem at a major regatta and badly effected my final placing. I have since returned to my old system and had no problems.
Cheers
Greg
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Bruce Andersen
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Post by Bruce Andersen » 28 Aug 2006, 01:14

If your'e into JR servos, their mini and micro digitals have metal gears, good quality ball bearings, and are stronger & faster than the full size analog ones. I've been using them without problems for 3-4 years.

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Re: rudder servo recommendation ?

Post by Lester » 29 Aug 2006, 17:11

VCinfocomms wrote:It should have the physical dimensions of a standard servo ...
Hi Anders

I too thought there was such a thing as a "standard servo" dimension, so replaced my old Futaba rudder servo with a new Hitec. Well, the difference of 1 mm was enough to mean I had to replace the servo tray with a new one, with a suitable opening for the servo body, clearance for the connector cable, and holes for the mounting screws... (smile)
Lester Gilbert
http://www.onemetre.net/

Andy Stevenson
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Post by Andy Stevenson » 30 Aug 2006, 10:03

I too thought there was such a thing as a "standard servo" dimension
Indeed, no such thing as a “standardâ€
Andy Stevenson
"A little pain never hurt anyone!" Sam, aged 11

awallin
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Post by awallin » 01 Sep 2006, 10:08

Thanks for the input guys,

I have just ordered a Spektrum DX6 radio for the new boat.

I've become really used to the Futaba 3VCS with the Spektrum module and the 'no antenna' look-and-feel. It's especially useful in rain or cold weather because the whole radio goes into the transmitter cover and there is no hole for the antenna where water could pass through.

Will have to check if it's possible to fold the DX6 antenna along the back of the TX to achieve the same thing with the new radio.

I've also found lots of links and descriptions to people who are changing the voltage regulator inside the DX6 to a more efficent one, thus more than doubling the TX runtime:
http://www.dimensionengineering.com/app ... um_mod.htm
I'll have to try that too!

As for the servo, I think I'll stick to a Futaba S3003 or similar 'standard' servo...

Anders

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Post by Doug Hemingway » 02 Sep 2006, 03:48

VCinfocomms wrote:Will have to check if it's possible to fold the DX6 antenna along the back of the TX to achieve the same thing with the new radio.
Sorry, Anders. 45 and 90 degrees forward only.
VCinfocomms wrote:I've also found lots of links and descriptions to people who are changing the voltage regulator inside the DX6 to a more efficent one, thus more than doubling the TX runtime:
http://www.dimensionengineering.com/app ... um_mod.htm
I'll have to try that too!
That mod is easy, cheap, and effective. Add a 2300 MAH NIMH pack to that and you can sail till midnight!

--Doug

Marko Majic
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Post by Marko Majic » 02 Sep 2006, 14:49

Wonderful find Anders... I ordered the part already! :lol: Will let you know how it works...

I already run my DX6 off a custom 2700 mAh NiMh pack (which lasts me all day) but (naturally :lol: ) couldn't resist something apparently so simple and with such dramatic efficiency improvement.

Marko
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Rob Guyatt
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Post by Rob Guyatt » 09 Sep 2006, 01:47

I've changed the voltage reg with the Dimension Engineering part in my DX6 and it has almost doubled the battery life. I use a 3 cell 1800 mAh LiPo in the DX6. That used to last just over 8 hours. Now it lasts 15 hours!!!! Boy I wish changing the regulator in the winch would give the same result. But alas no it won't. :(

By the way. There is a down side to this regulator upgrade. The back of the TX no longer keeps my hands warm. :wink:

I'd be carefull about moving the antenna on your DX6 Anders. While the DX6 system gives much better range than the original modular system, it is still possible to lose signal if the TX antenna is badly orientated. Anyone with this system can see what I mean if they sail out as little as 50 metres then point the TX antenna directly at the boat. It's critical to ensure the antenna is vertical. Obviously you will still orient it vertically but down if mounted on the back though

On the subject of servos. I'd like to hear any comment on the merrits of faster rudder control. I hear from some that high speed is useful especially pre start. Not being any good at pre start (or even the part after the start for that matter) I'm wondering how one could imrpove things with a quicker rudder. I'm not sceptical, just wondering. For what it's worth, I use JR digital servos in my IOM and RA.

Cheers
Rob

Marko Majic
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Post by Marko Majic » 27 Sep 2006, 04:01

Finally got around to it myself (installing the new voltage regulator)...

Tested it out with my 2700 mAh NiMh pack today - the transmitter started beeping after 11 hours on... Then stopped beeping (just flashing BATT) and continued working fine for another hour and a half... Voltage got down to 8.0V and stayed there for the last hour - but after that I just turned it off.

Probably could have gotten another 1/2 hour or maybe a whole hour if I didn't turn it off - but I don't think it would have lasted to Rob's whopping 15 hours (which, I guess, means that mAhs don't mean the same thing for Nickel and Lithium chemistries).

That aside - I'm fairly happy with the "upgrade" - 12-13 hours of runtime means I can sail a two day weekend event without worrying about charging the transmitter pack between days...

And (as Rob already mentioned) the transmitter runs totally cool (except for the little bit of heat from the green diode on the back) which is kind of nice (and makes one think that it might last longer)...

The only caveat is that (despite what it looks like a breeze on the Dimension Engineering website) - this project is for people with experience in soldering!!! I would not have put myself in that category but by the time I realized what was going on it was too late to turn back (as I have already half-broken the old regulator by then). The upshot is that removing the old regulator (body of which is soldered to the PCB) takes an ungodly amount of heat (and patience) and I was fairly convinced that I barbecued the RF unit by the time the old regulator came off... And prying the legs up can easily rip the trace from the board (first one came off for me but luckily it didn't break so I CA'd it back on). :lol:

Let's just say that no one was more surprised than me when my transmitter came to life when I hooked it all back up... :lol:

Cheers,

Marko
Marko Majic
CAN 16

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