safety issues

[RogueTwoRobots]

On the subject of failsafes the receiver appears to continue outputing the current position on all channels for one to two seconds after the transmitter is turned off. The throttle channel then outputs the failsafe position for about 1/2 a second before stopping all output while all other channels just stop all output.

So does this mean that, if I'm using an Electronize controller for example (without any built-in failsafes), I can just connect it straight to the receiver and the robot will stop moving when the transmitter is turned off, or would I need to fit an external failsafe between the ESC and RX?

[muchalucha]

On the subject of failsafes the receiver appears to continue outputing the current position on all channels for one to two seconds after the transmitter is turned off. The throttle channel then outputs the failsafe position for about 1/2 a second before stopping all output while all other channels just stop all output.

So does this mean that, if I'm using an Electronize controller for example (without any built-in failsafes), I can just connect it straight to the receiver and the robot will stop moving when the transmitter is turned off, or would I need to fit an external failsafe between the ESC and RX?

Yes , any failsafe built in to the esc are only really helpfull on 40 mhz systems. With the planet 5 set at least esc's without failsafes seem to failsafe ok .

[peterw]

I have now got three of the Planet RM6 receivers and it appears that there are two versions of the failsafe firmware.
The two boards with a date code 2409 (week 24 2009) have the system previously described but one board with an older code 0409 (week 4 2009) has a fixed failsafe which sets the output pulse to about 0.8ms for 1 to 2 secs before stopping the pulses. This is OK unless you have the channel reversed then it gives the servo fully in the other direction. I think most speed controllers are off with short pulses so they should failsafe. I don't know how many of these are out there I just got mine from Sussex Models but it is worth just checking how your failsafe works. I have emailed the distributors to try and confirm this and will let you know if I hear back.

[peterw]

Reply from distributor JPModels.co.uk
Dear Peter
Thank you for your enquiry.
It is the rx that controls the position of the throttle in failsafe mode. On early versions it just went to a fixed position.
The latest MII version of the rx with the Blue dot have the ability to remember the position the throttle was in when the rx is powered up. You have to go to the throttle position required on the tx every time power is applied to the rx. All the other channels just centre as before.
Glad you like the radios.
Hope this helps
regards
Julian
Just one point the blue dot refered to is a blue circular sticker on the rear of the case not to be confused with the blue dot on the front after the word Planet which is printed and on all cases.

[peterw]

I have just done a test with two different brushless speed controllers to see how the failsafe reacts. In each case I set the throttle to the centre before powering up so the receiver failsafe is set to half throttle. I then got the motor running at full throttle and turned of the transmitter. In each case the receiver took a second or two to recognise the signal was lost then slowed the motor to half speed for a couple of seconds as expected then as soon as the receiver stopped outputting pulses the brushless controller stopped the motor. It rather looks as though the receiver failsafe has little effect when used with a brushless controller at worst it delays the final failsafe by about two seconds.

[peterw]

Not wishing to complicate matters further but has anyone had any experience of the Radio Link 2.4 Ghz radio.
I found it on a site Giantcod.co.uk and here is the link.
http://www.giantcod.co.uk/gianitcod-24g ... 03779.html
It appears to have a few advantages over the Planet T5 as it has side entry connectors on the Rx, Elevon mixing in the Tx and a £25.48 price tag for a transmitter receiver combo.
The manual claims it is CE and FCC approved although the CE mark on the rx is not standard.
I have ordered one to do some testing and will let you know what I find.

[woody]

Be nice to have another cheap system.

[RogueTwoRobots]

Hi Peter, I saw the thread you made for the Radio Link system over on the RW101 forum and after reading the questions and reviews on the site I opted to buy one, so will be able to share my experiences of it soon (have made a thread in the general section for it).

As you say Woody, it would be good to have another cheap 2.4GHz option available, especially if it is suitable for all weight classes. I was one of the people against the decision to write 40MHz units out of the rules but with 2.4GHz sets costing this little, making the transition shouldn't hit wallets particularly hard.