Well, I'm pretty sure we'll make this work, so we still need to nail down an exact ° value to input for trigger location. One number for everyone. 
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Programmable advance TCI Replacement
- Thread starter 2XSive
- Start date
To plant a seed in anticipation of it working, we should take into consideration what would be needed to install this in earlier non-TCI bikes. Maybe a different pickup vs stock TCI?
The Hall Effect sensor you posted (don't know which variant), a bracket fabbed for it using existing stator holes, a rotor with magnet installed & an MP08 coil. What am I missing?
I PM'd Jim as I was gonna buy a pack of 5 of those sensors and ship a couple to Jim for testing. I wanted to make sure I had the right version, as the sensitivity and related air gap are different in a couple model nos. He pointed out that max operating temp is 100C, which may not be suitable.
As a Hall Sensor, you can use the automotive "Hamlin 55100" or a cheapo A3144 extracted from the KY-003 sensor from Ali: https://fr.aliexpress.com/item/1005001658739012.html
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OK, plugged in a 10k resistor. Not sure what to make of what I'm getting for numbers, but the end result looks promising. First the numbers with the sensor plugged into the box and the 10k resistor tapping the 12v line and running that to the output of the trigger.... like my half ass drawing a few pages back.
Sensor gap is at .025".
Output without the resistor is right around 1v.
With the resistor it drops to about 850mv.
Remember, this is with it plugged into the box. My previous readings were open circuit.... just the pickup. Still, I didn't expect voltage would decrease with the resistor... was expecting an increase. Thierre?
Now for the promising part...
Started at .025 gap, no resistor just to verify it's behaving the same as the other day. It is. Good spark until I open the gap to about .035-.040" then it becomes pretty unstable. Maybe a spark every 10 - 20 revolutions... just like before.
Next I plugged in the resistor and reset to .025" gap. Again, good spark.
Slowly opened the gap until spark was again unstable. Closed it down until it was again giving good spark. Shut it down and measured.....
We're now getting stable operation at .080" gap. Yes... eighty thousands gap!!!
Where to now Thierre? Try an 8kΩ resistor?
I'll play around some later when I get the chance and see if I can record some numbers.
Sensor gap is at .025".
Output without the resistor is right around 1v.
With the resistor it drops to about 850mv.
Remember, this is with it plugged into the box. My previous readings were open circuit.... just the pickup. Still, I didn't expect voltage would decrease with the resistor... was expecting an increase. Thierre?
Now for the promising part...
Started at .025 gap, no resistor just to verify it's behaving the same as the other day. It is. Good spark until I open the gap to about .035-.040" then it becomes pretty unstable. Maybe a spark every 10 - 20 revolutions... just like before.
Next I plugged in the resistor and reset to .025" gap. Again, good spark.
Slowly opened the gap until spark was again unstable. Closed it down until it was again giving good spark. Shut it down and measured.....
We're now getting stable operation at .080" gap. Yes... eighty thousands gap!!!
Where to now Thierre? Try an 8kΩ resistor?
I'll play around some later when I get the chance and see if I can record some numbers.
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Hey Thierre, what if we used a voltage divider?
Jim jim jim jim jim
I got a tub of early stators, mebby 10 of em?
I got a tub of early stators, mebby 10 of em?
You wantin' an aftermarket pickup are ya? Don't sugarcoat it, tell us what you really want.
Nope I'm just say'n there's available core stock for a new JimBuilt retro motorcycle product/service. ;^)
I can't keep up as it is.... 
Good guess Jim, it’s indeed a voltage divider ! 
The only difference is that I’m using the internal TCI impedance as the down resistor.
BTW Jim’s’s is 680ohm whereas Larry’s’s is 560, should explain one gets sparks but not the other!!
The external 10k with internal 680ohm gives a polarization of 0.7v. So the pickup needs to put out 1v to reach the minimal input of the TCI.
https://ohmslawcalculator.com/voltage-divider-calculator
>Where to now Thierre? Try an 8kΩ resistor?
Totally! An 8.2k wtih 680ohm would gives 0.9v. Even better!
whatchout. The 40° pickup internal resistance is in // with R2, so it must be took into account.
How much is it?
The only difference is that I’m using the internal TCI impedance as the down resistor.
BTW Jim’s’s is 680ohm whereas Larry’s’s is 560, should explain one gets sparks but not the other!!
The external 10k with internal 680ohm gives a polarization of 0.7v. So the pickup needs to put out 1v to reach the minimal input of the TCI.
https://ohmslawcalculator.com/voltage-divider-calculator
>Where to now Thierre? Try an 8kΩ resistor?
Totally! An 8.2k wtih 680ohm would gives 0.9v. Even better!
whatchout. The 40° pickup internal resistance is in // with R2, so it must be took into account.
How much is it?
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Sez the guy who built an RD700/4 engine.
So... some good news.
Video uploading as we speak.
Went down to an 8kΩ resistor on the V. divider. We're gettin a stable (kinda sorta) spark at 250rpm (start) and a solid.... fantastic spark at 1550rpm (idle).
Details in the video.
Video uploading as we speak.
Went down to an 8kΩ resistor on the V. divider. We're gettin a stable (kinda sorta) spark at 250rpm (start) and a solid.... fantastic spark at 1550rpm (idle).
Details in the video.
