|Gareth Jones||22/06/2020 08:04:22|
791 forum posts
I think Tim Rowe is correct in his explanation and the Spektrum DX6i does have protection against using the wrong transmitter settings with any previously bound receiver. The feature is called ModelMatch. The following text is taken directly from the manual:-
You must bind the receiver to the transmitter before it will operate. Binding is sharing identification codes between the receiver and the active memory of the transmitter. Once bound the receiver only connects to the transmitter when the previously bound model memory is selected.
I am pretty sure it does work like this as I have a number of different yachts programmed into my DX6i and have occasionally wondered why a model does not work, usually when testing something in the workshop, and I have found I had the wrong model selected on the transmitter. My memory is probably less reliable than the transmitters.
The basic channel settings are stored in the transmitter memory not the receiver. However some data must be stored in the receiver, apart from the transmitters identification code, if only to set up the fail safe settings. Fail safe settings might not seem so important in model boats but they can be particularly significant in model yachts with big powerful sail winches. I have had a sail arm servo tear itself out of its mountings when the arm came up against the extended keel inside the hull. It was my fault, I turned the transmitter off before the receiver, it went into the default failsafe mode which was throttle fully back and that was outside the normal travel range of the sailwinch. Nowadays I am more careful in making sure I have set the failsafe to the setting I need, not the default which is usually appropriate to a model aircraft.
Edited By Gareth Jones on 22/06/2020 08:07:01
|Dave Milbourn||22/06/2020 10:18:57|
3998 forum posts
Thanks for that, Gareth. I've not heard of that feature on any other brand of radio, but Spektrum always did things their own way. It does make sense when you think about it, but it means that if you move a receiver from one model to a new one then you need to rebind it with the Tx. It won't affect Brian's choice - he still only needs the one transmitter.
As regards failsafe it's a royal PITA for a model boat - unless it's powered with an I/C engine. It doesn't help that manufacturers all seem to have a slightly different way of settling into failsafe mode. Some will revert to a preset position for every servo; some will freeze all the servos at their present position except the throttle, which is returned to dead-slow or stop; some will centre all the servos before setting the failsafe position of the throttle. The only way to find out is to switch off your Tx and see what happens. It would be useful if one could simply turn it off. After all, modern electronic speed controllers invariably stop the motor if no valid signal is received.
|Malcolm Frary||22/06/2020 11:13:01|
|892 forum posts|
Always good to learn something new. Some swear by Spektrum, some swear at them.
A problem with failsafes on boats is that what is safe in one set of circumstances might not be in another. Probably "Safe for everybody else" should win, and slowing a power boat should be helpful. But I can't think of any setting that is universally safe for a sailboat. Planes and buggys that have been brought to a halt can generally be walked over to. Boats, less so. ESCs cuttng off to a signal loss was OK, no problem with that. But that was from the days of "dumb" radios that just passed information on. Some clever modern receivers think they know better, and do their best to retain normal service by remembering what they last heard and keeping that going. If it is just a few frames of information, OK, but any longer could create problems.
Dymo - a machine for permanently displaying mans inability to spell. I have fond memories of a row of part drawers where various indicators were kept in an office variously labelled "Inicators" and "idicators" and "idnicators". I have found that printing on a slip of paper and covering it with a length of Sellotape works and lasts well. Its what I did with the bind instructions for my Saturn transmitter. Very necessary due to the many unintuitive steps needed.
|Colin Bishop||22/06/2020 11:25:10|
4508 forum posts
Tim and Gareth are right!
Just found my DX6i handbook.
With patented Model Match technology you'll never mistakenly attempt to fly your model using the wrong memory again. .....
During binding the receiver actually learns and remembers the specific model memory that the TX is currently programmed to. Later, if the incorrect model is selected in the TX and the RX is turned on, the model simply won't operate.....
We live and learn...
|Gareth Jones||22/06/2020 12:13:43|
791 forum posts
I have to agree with Malcolm, generally I am quite happy with my Spektrum equipment but occasionally I have sworn at it, either because it has developed an intermittent hardware fault or because it has not done what I expected, usually because I did not read the instructions carefully. I do get the impression that current transmitters are not as robust as they used to be, although they are more sophisticated and do have some useful features, like being able to change modes on the sticks withouit having to take the back off the transmitter and fiddle about inside swapping springs and ratchets.
The failsafe situation is, as Dave, says confusing and some Spektum receivers set channels other than throttle to the last known good position, others can be programmed to put all servos in a preset position, chosen when setting up the system. However the throttle channel, which is the one I invariably use for a sail winch can usually be preset and I normally set the failsafe so that the sail winch puts the sails about 30 degrees out as a reasonable compromise to allow the yacht to be recovered.
Edited By Gareth Jones on 22/06/2020 12:28:06
|Paul Freshney||23/06/2020 16:19:57|
293 forum posts
A rare posting from me.....
All the manuals can be found online via the website:
under 'manuals' in the drop down menus.
I have a DX6i, Dx7s and Dx8, all quite old now (8+ years) and apart from replacing the battery packs they have given stirling trouble-free service.
The user can easily adjust settings on the work bench, the only minor problem being that the default fail-safe is usually neutral, except on the throttle stick where the electronics usually assume an i.c. engine, which only goes one way - forwards - so fail-safe will be with the relevant stick fully downwards and engine 'off'. However, the instructions tell the user how to circumvent this.
In fact if the user selects 'sailplane' - i.e. a glider, the parameters are changed anyway, but not the physical tension and/or ratchet on the throttle stick.
There is notably no model selection for 'boat', so you have to 'cheat' the system.
My Dx7s and Dx8 have the facility that the user can change stick mode, i.e. ratchet or self-centring, by twiddling screws in the outside back of the Tx. I think Gen' 3 Dx6i have that facility as well when checking online, but am not sure.
The safest thing? Fiddle around with it all on the workbench and get it right there, rather than at the pond side.
I have been able to use the RH vertical stick to control a bow door opening and closing from neutral, simply by adjusting the 'throw' of one extremity to zero, thus neutral (hands-off) was the closed position.
Model Match? Yes, that means if you switch on Model A at the TX and the model is actually 'B', nothing will work.
With a memory card you can also transfer all the settings from one Tx to another, if it has that facility.
I have long since abandoned the cheap generic 'orange' short range receivers. The more expensive long-range orange ones are ok though, particularly if used with a small satellite receiver.
I like the telemetry feature of the Tx's when used with appropriate Rx's so you can see motor rpm. battery usage, power demand etc. Alarm warnings can be built in when using Lipo's in the model as well.
Hope this helps
Please login to post a reply.
Want the latest issue of Model Boats? Use our magazine locator link to find your nearest stockist!
Make sure you never miss out on the latest news, product reviews and competitions with our free RSS feed
We welcome well written contributions from Website members on almost any aspect of Model Boating with a particular emphasis on practical hints, tips, experience and builds.
In order to maintain a consistent standard and format, all suggestions should first be sent to me by Personal Message for approval in principle. Only a very limited amount of time is available for editing contributions into a suitable format for placing on the website so it is important that the material is well presented, lucid and free from obvious spelling errors. I think it goes without saying that contributions should be illustrated by appropriate photos. I shall be happy to give advice on this.
The Member Contribution area offers space for short informative mini articles which would not normally find a place in Model Boats magazine. It is an opportunity for Website Members to freely share their expertise and experience but I am afraid that virtue is its own reward as there is no budget to offer more material recompense!
I look forward to receiving your suggestions.
Colin Bishop - Website Editor