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Trackball Optical sensors & RandyT's high resolution encoder wheels

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specfire:
I just purchased 4 TB's from Edgedamage (in the B/S/T forum).  They are all fairly old and 3 of them need to be rebuilt.  They are all HAPP.

One of the trackballs has RandyT's high resolution wheels (intended for 3" Imperial but mounted on a 3" HAPP), however, I am wondering if the optical sensor (being so old) is fast enough to track the much higher frequencies these new wheels would generate.  In other words, are these new wheels on old optical sensors a bad combination?  If so, would new sensors be much faster?  Is there a reason that these would not work on Happ TB's vice Imperial?

RandyT has a disclaimer on his site about slow PC interface controllers, but I am asking about the quality of the small optical sensors mounted on the TB itself.

I don't currently have an encoder to interface them to my PC so I can't test out my questions.

Thanks for any help,

specfire

NoOne=NBA=:
The only problems I've ever had with varying tooth sizes is that sometimes you have to push or pull the optic sensors a bit to line up better with the teeth.

I learned that one from Oscar.

I can't comment on the Happ optic cards specifically though because I've never tried varying the teeth on them.

Minwah:
I don't really know the answer either but...

I know Oscar used to use Happ-style encoder wheels on his spinners, and after that he released some custom metal ones with more teeth to improve performance.

I would think it should work fine.

u_rebelscum:

--- Quote from: specfire on September 29, 2005, 11:44:58 am ---I am wondering if the optical sensor (being so old) is fast enough to track the much higher frequencies these new wheels would generate.  In other words, are these new wheels on old optical sensors a bad combination?  If so, would new sensors be much faster?  Is there a reason that these would not work on Happ TB's vice Imperial?

RandyT has a disclaimer on his site about slow PC interface controllers, but I am asking about the quality of the small optical sensors mounted on the TB itself.

--- End quote ---

The sensors are simple phototransistors, and almost positively fine with new wheels.  ;)

The only problems you migh run into are IF:
(a) The sensor spacing and the tooth/gap widths are the same, a multiple there of, or very close to.  The "perfect" design (cough) is x=(n+0.5)*y, where x is the sensor spacing, y is the tooth/gap width (assuming tooth width = gap width), and n is the max number of teeth and gaps that can completely fit between the sensors.  The worst is x=(n+k)*y, where k=0 or very close to 0 or 1.  In this case, both sensors would trigger at the same time (they are supposed to take turns).
(b) The tooth/gap widths are smaller than the sensor's view width.  This sensor wouldn't be able to tell if the wheel is blocking the light or not.
(c) The sensor is not sensitive enough for very quick changes.
(d) The "wave square-er" (usually an inverter chip) is too slow.

The only one you might need to worry about is (a), because (b) isn't true for the not-that-much-thinner teeth/gaps in the new wheel, and both (c) & (D) are not that likely.  It's much more likely the PC interface is the slow spot, unless the circuits on the TB are going flakely (and need to be replaced soon, new wheel or not). 

That said, Happs came out with a new sensor board (the red ones) mostly for the super high speed golden tee trackball spins.  I didn't notice a difference between that one and the prior version, but all I did was play games - no measured testing. 

So, in short, there is the possibility that the new wheel might tip old boards over their limits, but I doubt it.

Level42:
We're talking light here, and light is a lot faster then everything else. Only thing is the speed of the photocell....My guess is it won't be a problem.

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