--Oz--'s blog View Details
Posted by --Oz-- | May 21, 2019 @ 12:05 AM | 1,563 Views
Look at the picture, this picture is amazing once you figure out what happened. The "T" in the top left of the picture is the scope trigger point, ball at rest (0 rpm) 25ms later, the ball is at 3.2 million rpm!
Name: 0rpm to 3.2Mrpm in 25ms - 250W.jpg
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I always set the vertical cursors to my current record (in microseconds), so I can see when I beat my personal best.
I usually prepare 10~15 balls for testing that day, one day, I got to this one ball, I guess things were just right (ball/container/angle/settings). What happened was amazing and unbelievable, with about ~250W (18V ~13A). First hall sensor trigger, it gave a ~0.25 second burst, I could hear the power supply give a quick 60Hz hum, sucking some juice, then the scope displayed high 2 million rpms! The major keys it was legit was no vibrations and the ball was still spinning down from momentum. I have been running the scope at 10us/div (since going for 2+ mil), but I decided to get the big picture, zoomed out the scope to 100ms/div and set single trigger and tried again, moved the hall sensor into position and it happened again, a burst of around ~250ms then hall stops triggering the coil. I zoom the scope into the end of the coil drive signal, this time just over 3 million in a quarter second! I stopped to think about it, no Ford transmission vib's, just pure signing spinning ball. Blown away I called a friend to witness what happened, I did it 4 more times, the most impressive time was in the picture, it shows 0 rpm to 3.2 million rpm...Continue Reading
Posted by --Oz-- | Apr 23, 2019 @ 12:50 AM | 1,032 Views
I bought a couple of these for $27 shipped on ebay, turns out they were different than the three I already have working (DPS-800GB). Different connector, so I needed to figure out how to turn them on.

As can be seen in the pictures, the 5th pad on top and bottom need to be shorted to ground and the supply turn on. The big pad closest to the edge is ground on top and bottom, of course next to it is 12V.
Posted by --Oz-- | Feb 13, 2019 @ 10:40 PM | 5,458 Views
I bought the M9-R on sale for $34 a pair 6 months ago, I just couldn't pass them up. Even though I did self modded hall gimbals in Jul 2016 and still work perfect, around 20K flights on them.

I wanted to use the short throw on the thro and modify the other gimbal back to normal 60 degree throw, also they will match color. After collecting dust for 6 months, in a couple of minutes looking at it, bingo, simply add four 1.5mm washers under the red ALU plate (see picture), now it has the stock ~60 degree travel like the stock gimbal has.

I took some OTX raw data and photos to compare travel degrees of all four axis. Looks like the raw travel numbers are within reason of the other axis (AIL and YAW) movements (+/-~100). These numbers have a lot to do with how close the sensor is to the magnet (closer gives larger range).

I took some pictures to compare my 1.5mm washer mod to see how close it is to 60 degrees. Roughly its ~1.5 degrees less than the other two axis (AIL & YAW). Of course there is some error in my measurements. I am pretty happy with a first try with 1.5mm thick washer guess.

I did the heat shrink tubing over the thro drag bar and a dab of rc car diff grease, this thro gimbal now feel as smooth as anything I have felt. So far pretty happy with them.