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Posted by PatMc on 11/06/2020 00:08:20:
Posted by Peter Jenkins on 10/06/2020 23:36:37:
Posted by Geoff S on 10/06/2020 22:37:55:

I assume Barrie Lever considers anyone using a Frsky radio a low calibre modeller with a poor reputation dont know

Geoff

It seems to me Geoff that anyone using Frsky radio apparently needs to know that you have to assign numbers to each Rx used.

No we don't.

Why don't we?

I genuinely don't know. I have gone to great lengths to do this (easy once organised), because I thought it was necessary.

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I'm sorry you feel that way Barry, FrSky have been around a long while now and have turned out some high quality kit at realistic prices and in my own experience have proved 100% reliable going right back to their first plug in module sets. But if you insist on regarding them as cheap Chinese tat then it's your loss not mine. Equipment has moved on a long way in 42 years, back then I was using Horizon, Fleet, Skyleader and the like and no, I don't want to see the like again. As just about all the electronics are made in China these days using common chipsets what's in a name?

I've witnessed Martin flying his Dalotels and Curare in recent years, he still puts on an impressive classic aerobatic display!

ps - re Martin's comment, will JR really only bind to a single receiver on any one model memory?

Edited By Bob Cotsford on 11/06/2020 09:37:02

Edited By Bob Cotsford on 11/06/2020 09:46:04

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ok, I may have blurred the line between Chinese and Far Eastern!

My Nats memories were more Ken Binks with his credit card 'side shields' tucked into the arms of his sunglasses. As I said Martin I saw relatively recently (? where do the years go, maybe not that recent thinking back!) at a classic aerobatics do putting his Dalotels and Curare through their paces, he could still put on an impressive show!

As an early convert to Open TX I can understand your caution but it really is developed and released in a very professional and controlled manner. User fiddling is really restricted to just using an expanded menu system, not in any way hacking the system! Previously I was using Futaba FF8 and FF9s and cannot sufficiently express the sheer frustration I experienced trying to force the proscribed menu systems to do what I wanted. Apparently I should have tried Multiplex but was an innocent back then. Now, with OpenTX, I can set models up to work exactly how I want no matter how unorthodox, and I can do it quickly and easily now I'm familiar with the architecture.

Dip a toe in, you might like it!

Edited By Bob Cotsford on 11/06/2020 10:45:09

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Posted by Steve J on 11/06/2020 10:18:21:

I despair of this forum some times. The OP has a DX7 that doesn't seem to know how to use and most of the replies are on the merits or otherwise of FrSky/OpenTx.

Same with any forum.

I posted a serious, but hopefully rare case where a poor lipo battery balance connection could easily have resulted in a fire had I not been more vigilant. All I got was several comments telling me what the problem could have been, yet I'd said exactly what the problem was.

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Posted by Barrie Lever on 11/06/2020 09:59:59:

I really don't like the amount of user fiddling that the open source rc systems allow, Pete Christy who I have enormous respect for tells me that I am worrying about something that I should not be, just makes me uneasy though.

Best Regards

Barrie

I would say without hesitation that OpenTX is actually far safer than most other systems with its inexpensive but comprehensive telemetry that can give advanced warning of several situations whilst flying. Add to that safety has always been at the centre of its development, and occasionally one can see this at the expense of simplicity. Also, I suspect, it has had more programming developmental time and field evaluation than all the other commercial systems put together.

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Posted by Steve J on 11/06/2020 10:18:21:

I despair of this forum some times. The OP has a DX7 that doesn't seem to know how to use and most of the replies are on the merits or otherwise of FrSky/OpenTx.

You make a good point Steve J. It was clear to me that he didn't know how to use his DX7 - and I hope that there was sufficient information in the post to help him on that point.

More worryingly, there are people, who like him, have not been taught to switch off the Rx before the Tx and continued to use that process. None of this would have happened had he done so.

I hope he now knows how to use the Model memories on his Tx and can bind to Rxs in different models with the correct memory selected.

There are quite a few newcomers whom I have come across who also have the following gaps in their knowledge:

  • 2.4 GHz aerials must be straight and not bent in a curve to maximise range
  • you do not need to put 2.4 GHz aerials outside the fuselage of wooden airframes. If there is any carbon fibre used to reinforce a model then keep aerials away from them. Only all Carbon or metallic construction requires aerials to be routed outside the airframe and the little aerial must be kept straight - also needs to be orientated as set out in the user manual
  • when doing a range check with 2.4 GHz, you must reduce the Tx power using the Tx specific process.
  • it is essential to know how to conduct a failsafe test. Failure to do so will mean that you have not taken reasonable precautions in the event of loss of signal.
  • It is definitely worth learning how to use at least 2 different rates on all 3 primary flight controls
  • It is worth learning how to use exponential, what it does and the importance of using it the right way - e.g. Futaba and JR/Spektrum operate in the opposite ways to each other.
  • it is nice to know how to use mixing correctly.

I hope that helps the OP as well.

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Posted by Steve J on 11/06/2020 10:18:21:

I despair of this forum some times. The OP has a DX7 that doesn't seem to know how to use and most of the replies are on the merits or otherwise of FrSky/OpenTx.

The OP did not state what transmitter was being discussed. The 2nd post assumed OpenTX, hence the confusion.

I have recently converted from JR to OpenTX, with an external multiprotocol module. It hasn't been easy and I am quite tech savvy. There are plenty of traps to fall into and each model needs to be thoroughly tested as a result. OpenTX is definitely NOT suitable for everyone, but is brilliant for anyone who likes to dabble.

The repeated brand bashing that goes on in this forum is futile. ALL modern transmitters are pretty good and reliable. You pays your money......

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Posted by Andy48 on 11/06/2020 10:45:53:
Posted by Barrie Lever on 11/06/2020 09:59:59:

I really don't like the amount of user fiddling that the open source rc systems allow, Pete Christy who I have enormous respect for tells me that I am worrying about something that I should not be, just makes me uneasy though.

Best Regards

Barrie

I would say without hesitation that OpenTX is actually far safer than most other systems with its inexpensive but comprehensive telemetry that can give advanced warning of several situations whilst flying. Add to that safety has always been at the centre of its development, and occasionally one can see this at the expense of simplicity. Also, I suspect, it has had more programming developmental time and field evaluation than all the other commercial systems put together.

 

Andy, my point was that no model radio system is designed and built to safety critical standards but best of that industry's standards. The more people who get involved in development, the greater the chance of some conflict being built into the software. No one, least of all me, expects the model world to use safety critical standards but equally, we should not assume that because I have an engine kill switch the model is safe. The BMFA guidance on electrically powered models is quite clear - once the drive battery has been connected the model must be treated as live at all times.

I've seen many examples of people arming their small electric aircraft with the prop buried in their groin! I wince, point it out and get told "Oh, its quite safe as my Tx has a kill switch so it won't arm till I move the switch". I've also seen folks walk through a crowded pits with large electrics with their kill switch operated and take no particular precautions to warn their fellow pilots they are walking around with 3 kw of power dependent on software from preventing it from starting.

For the avoidance of doubt, all full size flight control systems that are fly-by-wire are developed to safety critical standards and are backed up by 4 similar systems with a voting protocol to allow one to be in error. That assumes 3 will not be in error simultaneously! You can lose one system and still have a viable flight control system. Lose 2, which as far as I'm aware has never happened, you have a BIG problem! Despite all the checking that goes on, there are still errors that are found from time to time.

Edited By Peter Jenkins on 11/06/2020 12:09:39

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Posted by Peter Jenkins on 10/06/2020 23:36:37:
. . . To me, an aircraft is only disarmed when the drive battery is disconnected . . . Jeti make switches that are designed to be inserted between the drive battery and the motor and which can be switched by the Tx - that is clearly a great safety feature but they come at a cost. . . .

Any switch that can be 'switched by the Tx' is no better than any other Tx arming switch so, for me, disconnecting the battery is the only sure way to disarm.

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Posted by Allan Bennett on 11/06/2020 12:18:48:
Posted by Peter Jenkins on 10/06/2020 23:36:37:
. . . To me, an aircraft is only disarmed when the drive battery is disconnected . . . Jeti make switches that are designed to be inserted between the drive battery and the motor and which can be switched by the Tx - that is clearly a great safety feature but they come at a cost. . . .

Any switch that can be 'switched by the Tx' is no better than any other Tx arming switch so, for me, disconnecting the battery is the only sure way to disarm.

Agreed that disconnecting the battery is the best safety feature, but having two devices between the battery and the motor, i.e. ESC plus an isolator, has to make the process of connecting and disconnecting the battery (and perhaps moving the model once connected) safer. Both devices are unlikey to fail at the same time.

Dick

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I agree 100% Alan.

While switching off the receiver before the transmitter is best practice, those posting this good advice seem to have missed that the primary concern is to disconnect any flight battery as soon as practical after flight. Doing so removes any element of danger and should the receiver be left switched on, whether IC or electric using a separate receiver battery, the worst that will happen is an inadvertent undercarriage retraction.

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I don't fit an arming plug/connector to the battery/esc connection but to one of the motor leads. This has the advantage of allowing the controls to be checked whilst still preventing the motor from spinning beyond a short kick.

I've used the system on my Gypsy Moth successfully and I've done the same on my Sopwith Pup. These are both models where my hands have to be in the arc of the propeller when connecting the battery. All of my other electric models can be connected safely and in addition I have a transmitter arming switch on all my models.

Geoff

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I use arming plugs in the battery leads in my models where connecting the battery puts my hands in the way of the prop. I don't see the advantage of putting it in a motor wire unless it makes cable routing easier and/or shorter, but it does have the disadvantage that inadvertent throttling-up with the plug 'open' could damage the motor and/or ESC, and the motor will probably spin enough to damage your hand too.

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Posted by Allan Bennett on 11/06/2020 13:06:16:

................. I don't see the advantage of putting it in a motor wire unless it makes cable routing easier and/or shorter,

With the arming plug in a motor wire you can power up the ESC and hence the Rx if using a BEC. That way you can test out the radio without fear of the motor running - and no, it won't run or harm the ESC with one wire open circuit - just kick about a bit as Geoff said.

Dick

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Posted by Barrie Lever on 11/06/2020 14:29:30:

John

Agree about battery uncoupled, the only truly safe way.

Why are people so defensive about Friskey radios? Am I missing something ?

B.

Not defensive Barry, evangelical! And you will only know whether or not you are missing something by trying it wink

As the original responder let me make it quite clear, I was not making any assumptions about the brand of radio in question though I suspected it to be Spektrum, I was merely commenting that even model match isn't infallible. I added a comment pointing out that the latest OpenTX has attempted to address this point so I suppose I am responsible for associating the Trevor's problem forever more with FrSky. Mea Culpa face 14

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Posted by Barrie Lever on 11/06/2020 14:29:30:

John

Agree about battery uncoupled, the only truly safe way.

Why are people so defensive about Friskey radios? Am I missing something ?

B.

Not being defensive Barry, those are your words, weary of the cheap Chinese jibe though, It implies I take money more seriously than safety. I have never had a radio failure, explain that ?

Might be that said Martin still uses FRSKY RXs via a module, I could be wrong but It would be Ironic eh.

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