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thought PCM was good ? now there's SS.
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Knightrous
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Back on the Spektrum topic. What happens if you mount a Spektrum module into a module radio like the 9CAP ? Will the 9CAP loose all it's funky computer programmable functions? I propose a possible testing session, if it is okay with Andrew or Daniel and Nick. We can put Nick's Spektrum modules into either Andrew's or Daniel's 9CAP's and test it at the next HOC event.
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Post Thu Feb 09, 2006 3:43 pm 
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kkeerroo
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The frequency module on a radio is simply an RF modulator circuit and has nothing to do with the functionality of the radio but is for changing from one band to another. But unless the spectrum frquency module (do they even have frequency modules? I thought the wouldn't be needed.) is compatible with the Futaba radios in size, mounting hardware and electronic connectors (including pin in/out layouts) it ain't gonna work. Sounds far fetched to me since JR and Futaba modules are not even cross compatible.
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Post Thu Feb 09, 2006 5:00 pm 
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Nick
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According to the Spektrum site: "Compatible With: Futaba 3PK and 3PJ/ Hitec Aggressor CRX, Lynx, and SRX". They have another module compatible with the Aittronics M8 / M11, so the 9CAP will definitely not work as the module for it is quite different. There was some chat on the RFL forum and people there came to the same conclusion.
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Post Thu Feb 09, 2006 5:54 pm 
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Spockie-Tech
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In "PCM" mode, the data transferred between the Tx and the RX is quite complex, and has all sorts of addtional information in the stream for failsafes, error correction and many other things.

There are some web pages out there where people have attemtped to reverse-engineer the Futaba PCM1024 (and higher) protocols and found it a real black art, so I can understand why the Spectrum module wouldnt work in that situation..

*However*, Once you put the Tx into "FM" mode (which the 7Cap and presumably the 9CAP) will do, then the final modulated data stream that is sent to the RF module turns back into the simple variable-width pulse train that nearly all Radio's use, and there is no reason that a Spectrum module couldnt take that and encapsulate it in its own data packets.

In FM mode, all the clever mixing, curves, channel interrelationships and so on are all done in the Tx and end up as a simple "servo 1 goes here, servo 2 goes there" stream.

Using "FM" mode would not present any operational disadvantages reliability wise since the Spectrum Module would handle signal-integrity issues, I'm not sure how the the fail-safes might work though.

There may some minor some positive/negative signal polairty issues, but when you get down to it, just 3 wires go the RF mdoule. power, ground and data, and it should be easy to adapt a JR capable unit to run from a Futaba (ignoring physical mounting issues).
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Post Thu Feb 09, 2006 7:11 pm 
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kkeerroo
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The Futaba 9CAP frequency module (and presumably the 7CAP as well) is called FP-TP-FM RF Module and actualy has a 5 pin header inside. After opening one up a while ago I can asure you that PCM or not a frequency module is simply a RF modulator circuit only. There is no such thing as a PPM (Pulse Phase Modulated or more comonly called FM) or PCM frequency module. All the PCM stuff is done either in the radio and inside the receiver (the PCM recievers also have two seperate boards, an RF board and a "digital" board).
As far as interconnectivity goes with the Spektrum gear you should consider that the Spektrum company was actualy started by JR to test the whole 2.4GHz bit without jeperdizing their buisness if it didn't work out.
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Post Thu Feb 09, 2006 7:57 pm 
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Glen
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http://www.spambutcher.com/dx6.html
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Post Wed Feb 15, 2006 5:44 pm 
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Knightrous
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Won't work on the IBC/Victors....
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Post Wed Feb 15, 2006 6:14 pm 
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ffej
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Nothing stopping you from using it to disable the HIP4081's (H-Bridge driver) of any OSMC based controller . . .

From the HIP4081 datasheet:


quote:
Pin 3 DIS - Disable input. Logic level input that when taken high sets all four outputs low. DIS high overrides all other inputs. When
DIS is taken low the outputs are controlled by the other inputs. The pin can be driven by signal levels of 0V to 15V (no
greater than VDD).



Sure, this would be bypassing the controllers brain completely, but I dont think that really matters, it will failsafe in any case.
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Post Wed Feb 15, 2006 6:35 pm 
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Knightrous
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Good point Jeff. Isn't too hard to push a bit stripped 30g wire down the socket plug with the HIP Chip.
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Post Wed Feb 15, 2006 6:41 pm 
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Valen
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add just a little brains to it and make it output a mid range pulse on both chans
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Post Wed Feb 15, 2006 9:47 pm 
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Daniel
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quote:
Originally posted by Jim Smentowski on the RFL forum:
Alright, it looks like we have worked out a resolution here:

Announcing the new Spektrum BR6000 Bot Receiver 2/21/2006

Spektrum's new BR6000 receiver is designed for robot and special application usage where it's desirable to have the failsafe drive all channels to a preprogrammed position during loss of signal vs. hold the last command. This is ideal for applications where it's necessary to shut down systems (ie. weaponry, drive motors, etc,) during loss of signal to prevent an unsafe condition. If you currently own a DX6 radio and are using it in a robot application, you'll want the new BR6000 receiver. You can order SPM6000BR or simply return your AR6000 receiver and we will exchange it for a BR6000. Send the AR6000 receiver along with your name and address to Spektrum Service, 4105 Fieldstone Road, Champaign, IL 61822. We will quickly send out the BR6000 receiver in return!

We will have the BR6000 available in the Robot MarketPlace shortly.

Post Wed Feb 22, 2006 1:13 pm 
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Rotwang
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http://www.botmag.com/articles/spektrum_radio.shtml

Very Happy

Post Wed Feb 22, 2006 1:47 pm 
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Valen
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its not just for robots that you would want that though,
Pretty much all aero and track apps would want it.
Helicopter, center the cyclic and trim the collective for a slow decent.
Plane trim the thing for straight and level with a slight decent and idle throttle.

RC-Car, straght ahead and idle throttle.
if the last command you gave your RC car was full ahead it isnt the sort of thing you would really want it to continue doing off into the horison/barrier ;->
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Post Wed Feb 22, 2006 2:28 pm 
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Knightrous
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*Goes and orders a Spektrum DX6*
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Post Wed Feb 22, 2006 2:28 pm 
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timmeh
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YESS WOOT ORDERS ONE TOO!
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Post Wed Feb 22, 2006 3:48 pm 
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