I signed up just to say, this is awesome. and how do i get one / help

I think there's no 'official' way to get one, you can make your own starting from the schematics that you can find in the thread. The difficult part is to program the PIC (or other microcontroller used) with the correct program. I think that through the posts you get enough info to write one, or Howard might be distribuiting his program that work with his decoder (no Mylaps compatibility).
The transponder can be prototyped quite easily as shown in the images, I'm about to test a new 8 pin PIC that should be able to do everything with just 1 chip.

Nice work! I

Hi everybody,

first of all I have to say thanks for such a great threat you did here! Amacing how many people work so hard one this project.

I´m really interessed to build also my own transponder, so I have some questions I could answer myself in this threat. Maybe some off you guys can help me with you experience.

I would like to use a transponder of a full size cross car. So the distance between the loop an the transponder will be anround 1 meter. In #332 I read that the distance is ambout 15 cm. Is there a way to improve the distance? What are the parameters to play with?
Is there a difference in using a coil induction instead of the onboard induction? In this case I could save some space and could chance the direction of the transponder to the ground (So the PCB not need to be perpendicular to the ground).

I´m already working at a transponder for a half year but I had a different approach because I could´t find the way professional transponders work till now

I was using the loop as an transmitter with an tone of 8 kHz and 24 V. With the transponder I´m able to detect this tone by FFT. When the transponder detect the loop it send it´s ID via a rf 433 MHz Module to the Timing PC. It is working ok for now but it´s kind of "I don´t know what I´m doing" approach.

Since I try to build the hole system, I don´t have to be compatible to other systems.
So I hope with a little help I can design a real transponder. Already thanks for the great support!

Edit: would it be possible to use hf transistors behind the uib and uic to use higher voltage to improve the distance?

I just tested CANO transponder and it successfully working with RCHourglass.

Sorry ATTINY 25 transponder "is" compatible with RCHourglass decoder. But detection distance is short.

Very strange. Please detail construction mode (PCB/manual type). Also, is any packet detected in MONITOR MODE in RCHourglass?

Thumbs up!

I found (after 3 years or so) that I send the preamble twice in my code for the attiny transponder and this might cause some issues. So check if that is your case. Or you might be using howards attiny code then this should not be an issue. How is the Antenna designed on your version? There is huge difference in range on all different antenna designs that have been floating around.

I have started a rewrite of the code in the Arduino software with bugfixes and support for the extra status messages. I wanted to take the step towards more open source tools instead of the windows only avr studio.

Code will soon be ready for test: https://github.com/condac/openAST

Hi! Nice thread!
I´m into motocross + enduro and also electronics.
Is there anyone who tested this design vith the RC4 decoder?

Yup, tried it and the Cano Tx counts on an RC4 decoder but randomly misses laps. This is intentional from the RC4 decoder and makes it useless.

The Cano Decoder will detect hybrid Tx (Harry) but not the RC4 dedicated Tx (Percy)

Hey all,

I can generate all the required packets (main + 7 status) for your transponder ID. If you've got a DIY transponder and want to try full status packet support, send me your transponder ID along with proof of a recent donation to a children's charity of your choice (any amount, same as mv4wd asks for RCHourglass) and I'll send you the packets.

Heads up, this is experimental and untested against an actual MyLaps decoder so no guarantees yet.