Lynxmotion Tech Support

Looking great Kare!

Oh BTW Kurt and EddieB, I still have the antenna mounts we forgot to send. They are here if you guys want them. Just let me know...

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

I was sort of wondering what to do there and now it makes more sense. I was going to try out one of the 2.4GHz antennas from the WiPort too though so I wasn't stressing too much. I need a couple SEA-01 for that other project there so I'll place an order later this week and put a note on it to bring it to your attn. so you can throw it in the box if you get the chance.
EB

You can build some pretty decent 2.4ghz antennas with little work although id just buy some high gain omni's like the ones used on linksys radios with the reverse TNC connectors.


On the previous page of this thread I noticed that you guys had some code that allowed the phoenix to drop when the radio was turned off, there is a pin on quite a lot of these receivers and the voltage changes on this pin due to signal strength coming off the transmitter and goes to some voltage when the transmitter is off, this pin isn't accessible from outside the receiver so you need to crack the case and find it,

I know this is the case for some of the analog futaba receivers.

--Aaron

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Is the warranty voided yet? ... and why not?

Hi,

I've done some testing with the v1.2 transmitter code and Kurte's receiver test code. And the receiver code works great, I measured an average reading time for all channels to 15 mS ! Much better than the way I did it (reading all pulses in two rounds). Great work with the code Kurt!

I've some questions about powering the DIY. The battery Jim provided is that NiCd or NiMh ? What are the recommended charging rates? I charged it ones but it didn't last for more than 30 minuttes. The battery is rated 1600 mAh and the DIY draw 270 mAh.

Does anyone know what voltage range the Spectrum DM8 support? I didn't find it in the documentations, only for the receiver.

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[b]Kåre Halvorsen, Zenta[/b]
-----------------------------------------
Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
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Hi zenta,

You should build your own pack like i did



As for charging rates, I use this
and I charge it at 5.0 amps takes around 45 minutes or so.

as for lifetime I believe its around an hour or so?? I haven't actually had my phoenix operating until the thing beeps at me due to low voltage.

they are 5x 4700Mah NIMH cells I had bought online.. they are the largest capacity in current available in the subC size without going to a more radical battery like the lipo. and at around 5-7 dollars a cell they are quite inexpensive to construct your own pack.

It also fits nicely in between the two plates of the phoenix.

and i don't have a picture of it.

either way BUILD your pack! and get a sweet charger for it, that charger i have charges everything pb, lipo, nimh, nicad, Ion,

genius. GENIUS.

anyway..

--Aaron

_________________
Is the warranty voided yet? ... and why not?

Hi LikWidChz,

I'm not sure if I need more amps for powering the DIY remote, since the battery supplied are rated 1600 and the DIY draw about 270 mAh.

Another thing is that I doubt I would make a large battery pack fit into the DIY case.

Thanks for your suggestion though!

When it comes to powering my A-pod I'm using LiPo, I recently bought two of these:




I just had to beat Xan's beefy 4900 mAh polyquest...

---
Ok, I don't want this thread to get off topic. So any answers to my previous post are appreciated.

_________________
[b]Kåre Halvorsen, Zenta[/b]
-----------------------------------------
Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
-----------------------------------------

Hi Zenta,

Jim provided the DIY with a NiMH battery. I’ve purchased a universal Turnigy charger for the Lipo which I’m using in the phoenix. I’m also using it for charging the DIY. The charger let me choose a program (fast charge, tickle charge, discharge/charge) and takes further care of the configured amps. The charger automatically stops when it’s done. What kind of charger do you use?

I’ve configured the fast charge program to 1C and the tickle charge to C/10. So i think the fastest recharge time is 1 hour...

Xan

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[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

DAMN!!

_________________
[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

Thanks Xan,

I'm using a iMAX B5 charger. I've been very pleased with it until now. I'll give the battery a second chance and try charging at 1C again.

_________________
[b]Kåre Halvorsen, Zenta[/b]
-----------------------------------------
Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
-----------------------------------------

The batteries are NiMH. They require several charge/discharge cycles to get into spec. We buy them in large quantities in order to keep the prices low. So it's normal to have to do this when NiMH batteries are stored for a while.

The AirMod is made for a standard Futaba radio which is powered from 9-12vdc depending on battery type. I have powered it up with as little as 5vdc and it did operate. I don't know if the range was effected. In fact I haven't tested the range yet. Has anyone else tested the range yet?

_________________
Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Ok, that explains it. I did notice that my charger only took about 30 minuttes to charge it with a 1C (1,6 Ah) rate.

The second time I charged it, (after posting my Q's) i lowered the max charge rate to 1Ah and this time my charger took 135 minuttes for a complete charging. Sounds like the battery was able to receive much more "juice" this time.



Thanks for information.

I've not tested the range, but I doubt it would be any trouble for robotic use.

BTW:
Do you know if its possible to use the AR7000 receiver without using the slave receiver? I tried to use it without it, at first it didn't work but after about 1 minute it started to work again!?

I also tried to BIND the DIY and the AR7000 without the slave receiver, it worked but I still had to wait for about a minute..

_________________
[b]Kåre Halvorsen, Zenta[/b]
-----------------------------------------
Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
-----------------------------------------

I think I read somewhere that the receiver will work without the second receiver module. Can't remember where.

I know robots don't need a large range, um unless they do. lol Really I'm just wanting to see what sort of range the radios are getting, that's all.

_________________
Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

This project has been very fun to be a part of! I have learned a great deal about what's possible with standard off the shelf components. At the same time I've gotten the bidirectional communications bug from Kurt.

Looking at Zigbee modules which at the lowest power level can work indoors up to 400ft. At data rates up to 250kbaud. My question is concerning baudrate, error checking and correction, and how much data can be sent with serial data. For example I know with the DIY radio that 7 channels of data with 1uS resolution and a range of 1000 can be sent in 23uS. When you move the stick on the radio the value changes in what appears to be real time. If all we have to utilize is the serial data stream, can it "keep up" so to speak?

Without getting too far ahead of myself I would like to make a system that has the ability to be expandable to more than 7 channels of data, so I need to know the bandwidth is there.

_________________
Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Interesting topic,

I really doubt you would see a propagation delay...

why not send the code twice or 3 times?

what about send the code with a check sum calculated on the fly..?

As for more then 7 channels of data, I think the term "channel" has to be looked at a bit more closely, your sending it serial data you have as many channels as you need, I think the limitation is the transmitter/receiver ...

You think about just using a serial transmitter/receiver combination that way you don't have to take data -> convert it to PWM then go back to code.. "SEEMS LIKE A LOT OF STEPS"

I would try and see if there is some form of serial transmitter receiver combo on the market "Granted I know these aircraft 2.4ghz transmitters receiver's have gotten like a million times better then what they were 10 years ago" and the range is stupid good.

... Here I go off on a tangent..

You think its possible to develop sort of a reverse SSC32 board?
"take a receiver and connect it to some inputs and then that serial data is piped out of some pins?"

Kurt -- I haven't had a chance to look at that code you made yet "not like I would understand it anyway" I still need to obtain my servo extension wires so I can mount my Futaba R168DF receiver to my Phoenix

....Infact here's an idea you think its possible with new code to the ssc32 you could actually have it accept inputs? so then you can feed the input pins PWM data and it gets translated to serial code rather then have the ATOM chip handle the pwm-->data conversion?? It would basically take kurt's code and somehow someone would convert it to work on the atmel chip "somehow"

Not sure if that ssc32 board is even able to do something like that , sure would be a lot of input channels! and if that's the case the board wouldnt even have to be re designed, would be pretty scheweet.



Anyway those serial transmitters did a quick google search and check this out [/url]http://www.globalspec.com/FeaturedProducts/Detail/BlackBox/900MHz_Serial_Transceivers/39818/0[url]

Not sure if you needed bidirectional communication, although I remember seeing something on parllax's website that worked something like 400 feet? I would put a link but it looks like there website is borked.

Either way my 3 cents for what its worth, or just to toss some more ideas into the mix o ish.

--Aaron

_________________
Is the warranty voided yet? ... and why not?

Sorry about that


My guess is we will have plenty of bandwidth for this. To do the simplist conversion we simply send 2 bytes for each of our current channels. Obviously we could convert the keypad to a single byte as we only have 17 values.

We can then experiment with different communication protocols. Things like maybe only send information on what changed. This could be with a simple 1 byte header with one bit for each channel and then only send the bytes for the ones that are set in the header byte...

I will start my experiments soon. I have a few XBees and a few Xbee Pros, some version 1 some version 2. What I did not know when I ordered them before are there are different types of nodes. End points, Routers, etc. Also did not know that there are different network meshes for them. So I found a needed the capability to reprogram the XBees. The PC USB board should arrive tomorrow. The fun will be we can setup up repeaters(routers) to extend the range.

Kurt