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Ah good point Leo! I have not been able to test this yet, so maybe some sort of testing can be arranged at Barnsley when there are other 2.4GHz units about. Thanks for mentioning that.
Tested Carcinus yesterday with it and got excellent range on it - not sure of the exact distance in metres but definetly sufficient to cope with robot events.
I've also purchased one of these and a couple of receivers. Tried the failsafe by turning off the transmitter while it was driving a motor and it worked fine although it took a second to kick in, unlike my 40 MHz which kicks in instantly. But a one second delay is perfectly acceptable for a robot in an arena. It also takes a second or so to start up when the transmitter is switched back on.
I read up that the planet 5 system uses new cheap internals, could someone break there's open and take pics , id be really interested to see if the innards are the same.:)
Crack open a Planet 5 or crack open one of these Radio Link ones? I've got a picture or two of the internals of the Radio Link system that I could upload in the morning but it's very simple. One circuit board fitted down the bottom of the transmitter casing; the sticks, LED and battery connections just plug in to it, there is a PIC chip or two, and a small circuit board that seems to be the 2.4GHz 'module' stacked on top of it (similar thing is fitted in the receiver)
So yeah it's pretty simple. Been a while since I took my Skysport 6 apart but I remember there being L shaped circuit boards fitted round the sticks and everything on that one, but for the price you pay for a Radio Link unit the level of simplicity is no surprise.
is the 2.4 ghz board a sort of small triangle with platish edges?
Just a couple of things to add.
I have found that if there is another 2.4Ghz tranmitter operating within about 300 mm of the receiver when the system is switched on the receiver never seem to lock on to the transmitter. This is in normal operation not binding. If the other transmitter is switched off or moved further away control is established and then placing the transmitter back in close proximity to the receiver has no effect. Not a major problem but I was doing some tests with other transmitters to check the operation and thought the system had stopped working.
The other thing is the failsafe as stated above all four channels stop outputting pulses when the signal is lost so you are reliant on the speed controllers for failsafe. On the throttle channel when the signal first connects or reconnects the receiver outputs the minimum 1ms pulses until the throttle stick is placed in that postion then the pulses follow the stick. Strangely that is stick full forward as standard so you need to reverse the throttle channel.
All round I am most impressed for a £15 Transmitter and a £10 receiver.
Receiver size and weight are a little high for ants but as the receiver is 12.5gms and its case accounts for 6gms there are ways to reduce it.
The RF part of the receiver is on a tiny daughter board 23 x 15mm see picture:
http://i109.photobucket.com/albums/n66/ ... MG0922.jpg
I am looking at the possiblity of building a dual controller board that sits on the servo connector pins and fits within the existing size of the receiver.
I will need to replace those two large capacitors.
I now have a working antweight controller running.
Here is the receiver insides as it comes.
http://i109.photobucket.com/albums/n66/ ... MG0922.jpg
I have managed to replace the two large capacitors with small surface mount devices and removed all but 5 of the pins and turn the arial and it still works.
http://i109.photobucket.com/albums/n66/ ... MG0937.jpg
The built up board looks like this:
http://i109.photobucket.com/albums/n66/ ... MG0939.jpg
Fully finished it looks like this with a standard receiver next to it:
http://i109.photobucket.com/albums/n66/ ... MG0942.jpg
Original Receiver....... 44 x 30 x 17mm and 12.7 gms
Controller Module...... 42 x 27 x 11mm and 11.5 gms
Nice job. Very impressive.
I asked the chap at Giantcod if he could confirm that the RadioLink gear has CE approval and if he could publish the documantation and got the following reply.
Yes I can confirm it.
I will put all the cerficates on the site later.
Regards,
Rob.
www.giantcod.co.uk
Used the Radio Link Tx/Rx combo in Carcinus for a fair few fights at Barnsley at the weekend.
In general, in performed very well. The robot failsafed without any problems both on the bench and in the arena. Signal wise, there were no problems in the arena, full control was retained for the duration of all its fights.
However, the issue Peter describes above of the transmitter and reciever not conecting when turned on in close proximity to other 2.4GHz sets occured during arming-up in one battle. We tried turning it off and back on again several times but signal couldn't be established. We removed the robot from the arena and tried again when it was on the pit bench (away from all the other active 2.4GHz sets) and it connected fine.
There are two or three ways I can think of to get round this:
1) Use a seperate Rx battery supply (i.e. not a BEC) and turn on the transmitter/receiver when you first take your robot into the arena (before everyone else turns their transmitter on). This way your tx/rx can connect without interference yet there is no risk of your robot's drive or weapon moving due to the fact that the link still needs to be plugged in. We did this for the fight after we had the connection problem and it worked fine.
2) Wait till everyone else has turned on their transmitters (and keep a bit of distance between your robot and others) and then turn on your transmitter.
3) Possibly a bit of a hassle, but mount your receiver/design your robot in such a way that you have a small access hole through which you can stick a thin screwdriver to press the bind button on the receiver and renew/re-establish the connection if needed.
This issue may sound rather troublesome but hopefully this shouldn't happen every time you arm up. It only happened during one battle out of six over the weekend for us; I guess it just all depends on the circumstances at the time.
That aside, for £25 it performed rather well and is a nice option for those just starting out building a robot in need of a transmitter/receiver.
Just to add too for anyone who's not had a look round the site, GiantCod also have a 6ch version for £52:
http://www.giantcod.co.uk/giantcod-24gh ... 03852.html
It is computer programmable and looks very similar to the Field Force 6 in terms of its buttons etc.
Also, for those who use Deans connectors, they sell ten pairs for £4. They're not actual Deans but an equivalent make and according to reviews, they work very well on their own or used with proper Deans conenctors. A nice money-saver:
http://www.giantcod.co.uk/deans-style-u ... p-208.html