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mekzoid
02-11-2014, 07:01 AM
Hi all,

I have ordered everything for the cheetah now apart from the lipos and radio gear.

I need a transmitter, If its pistol grip it has to be convertible for left hand (like the dx3r pro) as I prefer racing that way.
I used the dx3r for on road racing for years but sold it last year.

I like the idea of the stick air transmitters, Can these be used reliably for water applications?

The reason I need a long distance reliability is where I will use it is along a water front with sunken rocks in close, So need to go out a fair way, Then have a nice run up and down ( to a point where I will just be able to see my boats).

Just after a few different ideas apart from the spektrum pistol grip range for a controller that wont cost me more then $200 used/new.

I have a feeling I will be going with another dx3r or the new dx4 purely as I can swap it around for a leftie, and the programmable options.


I have read through 16 pages of old threads for the search term transmitter but nothing comes up for what I am after.

Cheers :)
Todd.

siberianhusky
02-11-2014, 08:35 AM
Spektrum air transmitters will bind no problem to the marine rx's, I use a dx6i for sailboats.
Can't see any difference in range, still the same antennae on the receiver, with my electrics using a DX2s or sailboat with the dx6i I have more range than I need, I know the eyes are getting older but when I can't see anything but a roostertail or sail I have enough range.
I do run the antennae up a tube to get it out of the hull on the electrics, attach it to a stay on the sailboats.
The only time I ever had a range issue I was using a non marine (sr3000 telemetry, the one the DX2s came with) surface rx , pretty sure the short antennae was going below the waterline when it was turning.
I've heard stories about fliers using the marine 3 channel rx in 3 channel (rudder, elevator, throttle) sea/float planes with stick radios, never actually seen it done in person, no idea if it's just internet talk. They fly farther out than we run boats usually. This is up in the air though so they have better line of sight.
No experience with Futaba 2.4 stuff only the older AM and FM stuff, changed to Spektrum when I switched over to 2.4. Oddly enough same year I switched from nitro to electric....

Darin Jordan
02-11-2014, 08:39 AM
Spektrum air transmitters will bind no problem to the marine rx's, I use a dx6i for sailboats.
Can't see any difference in range, still the same antennae on the receiver, with my electrics using a DX2s or sailboat with the dx6i I have more range than I need,

Just of note... the current batch of Spektrum surface Transmitters (DX3S, DX3R-Pro, DX4S, DX4-Pro, DX2S, etc.) with the "Marine" logo on them use the same "protocol" as the Air series of transmitters. There shouldn't be any difference in range.

Fluid
02-11-2014, 10:27 AM
Current Spektrum and Futaba 2.4 gig radios are good to at least 1000 feet on the water, I have used both for SAW racing. Make sure you have an external antenna - which you will need anyway with your CF hull. Stick or wheel? Ford or Chevy. Either works.


.

mekzoid
02-11-2014, 06:23 PM
Excellent thanks guys just the info I was after.
Might try a cheap dx5 stick and see how it works for me.
Thanks again! :)

Doug Smock
02-11-2014, 06:33 PM
Current Spektrum and Futaba 2.4 gig radios are good to at least 1000 feet on the water, I have used both for SAW racing. Make sure you have an external antenna - which you will need anyway with your CF hull. Stick or wheel? Ford or Chevy. Either works.


.

My experience mirrors Jays.

kenrid
02-12-2014, 07:34 AM
BUT...I have a Spectrum MR200 Sport Marine receiver, (cost $85 AUD) with two antennas, how can that work in a carbon fiber hull? I thought the antennas are supposed to be kept at 90 degrees. Does anyone run this receiver in a CF hull?

Rocstar
02-12-2014, 09:21 AM
I run the longer antenna outside my CF hulls and just leave the other inside. Works well on my SAW boats.

olwarbirds
02-12-2014, 02:33 PM
Spektrum "Marine" rcvrs have been designed to deal with range and CF with 2 ants one should be vertical (going outside of hull) other along a horizontal plane...This is info I got at our Hobbyshop from the Horizon dealer net....yes the stick aircraft radios will work, but according to what I understood the surface radios would be a better choice .... I know we been using the stick radios in sailboats for years with no issues...have fun... DJ

mekzoid
02-12-2014, 11:00 PM
I am actually glad you asked that question kenrid as I was going to stick both antennas up in the air as high as they can go.
thanks olwarbirds for the advice, Much appreciated!

TheShaughnessy
02-13-2014, 07:55 AM
you need to increase the output if you want more range. Take some notes from this fpv pilot http://www.fpvpilot.com/Pages/LongRange24Radio.aspx

more range then you could ever use line of sight.

olwarbirds
02-13-2014, 09:25 AM
I am actually glad you asked that question kenrid as I was going to stick both antennas up in the air as high as they can go.
thanks olwarbirds for the advice, Much appreciated!

YW bud, Ive been using Spektrum products almost since they became available, very good quality and the customer service is the best...Ive even done the FPV Line of sight Plus without having to change a thing....As our very Knowledgable buddy Darin J has pointed out Spek surface and air rcvrs are using the same protocol now so range is beyond what our eyes can see.....Spektrum power output is at the current LEGAL max .... These guys increasing this are doing numerous things ...voids warranty, breaking law..causing probs for all us legal fliers, Im not tryn to start a debate here I just know whats been happening to alot of us who do or did fly big RC scale Jets and warbirds...we came close to loosing this privaledge and its got alot to do with FPV....DJ

Darin Jordan
02-13-2014, 09:56 AM
On most of my boats, I only run about 2-3" of the long antenna lead outside of the boat. The other lead is laying inside the boat somewhere. The only part of these leads that is actually "antenna" is the last 31mm.... that silver stripped portion. These are coaxial cables, not wire, so the gray portion is a shielded outer covering. The silver-ish inner part is the actual antenna.

As long as this portion is exposed, and not blocked/shielded by any parts of the boat (cowl, wing, etc), you shouldn't have range issue.

On my SAW boats, my antenna is only 1.5" to 2" long, and that competition involves the LONGEST distances we usually ever have to drive the boat's from the driver's stand. I haven't had a range issue yet. Some of the guys running the BIG cats I've noticed have had some spotty-ness WAY out there, but I also notice that they are standing down on the ground, and often pointing the top of the transmitter down towards the ground (for example, when they get the boat WAY out there and then relax while they wait for the ripples to die-down), and then they may have issues. With these VERY big carbon boats, I would want to run the antenna out full-length to get the tip to clear all parts of the hull. However, I suspect that, if they were up on a driver's stand, or up on the picnic table where Billy and I usually stand, and would keep the TX in hand and up and ready, there likely wouldn't be any loss in signal.

mekzoid
02-13-2014, 05:57 PM
The only part of these leads that is actually "antenna" is the last 31mm.... that silver stripped portion. These are coaxial cables, not wire, so the gray portion is a shielded outer covering. The silver-ish inner part is the actual antenna.
From my 10 years or so racing 1/10 scale ep on road around Australia, I never knew that lol. Thanks mate.


Such great advice here, Thanks a lot.

My parts are sitting in Chicago USPS....so an excited wait ahead for them to reach Australia.
Ill be updating my build thread as I go.

Fluid
02-13-2014, 06:48 PM
From my 10 years or so racing 1/10 scale ep on road around Australia, I never knew that lol. Thanks mate...
Ten years ago we used AM and FM radios which had much different "tuned" antennas. It is just the 2.4 gig radios which have the short antennas at the end of the coax.

Good luck with the project, I will be watching with interest...



.

Darin Jordan
02-13-2014, 07:26 PM
From my 10 years or so racing 1/10 scale ep on road around Australia, I never knew that lol. Thanks mate.


Such great advice here, Thanks a lot.



Please keep in mind that I'm referring to the current batch of MR series receivers from Spektrum specifically. Others may be different.

beau0090_99
02-13-2014, 10:05 PM
Darin,
You're right, if there are any 2.4 antennas that are longer than 31mm, the extra part that looks different is the coax cable. The active element is going to be some factor of 31mm since that is the quarter-wave length of 2.4gHz. You can amplify your antenna by making it a dipole (changing that coax to run the shield back down the gray part another 31mm), but that is advanced and if done wrong you can shorten the reception range too. What we have in our radios is more than enough range for most hobbyists, even those that need to run out beyond the rocks. The key is to make sure the antenna is elevated above the water (the ground plane) and make sure it is never in a position to point directly at or away from you. This is the benefit of the diversity Rx (2 antennas at 90 degrees), if one of those is pointing at or away, then the other is perfectly perpendicular to you and in full gain. An antenna tube that elevates it up off the water and keeps it fairly straight up is great. Also, keeping your Tx antenna mostly straight up will couple better with the the vertical Rx antenna.

Have fun,
Curtis