[TowerTalk] New product idea

[Lux, Jim]

On 8/30/22 6:16 AM, John Simmons wrote:
> OK gang, who want to make money on a side business?
>
> Design and build a hall effect replacement for the HyGain rotor 
> position pot. This part is the weak link in the rotor and new factory 
> parts sell for $65. I'm thinking lots of people would pay $100 for a 
> better part.
>
$100 retail price means the raw material cost should be ~$10-15.

That's pretty challenging.

Hall effect isn't great at sensing 360 degrees, it's more like a reed 
relay sensing passage of a gear tooth or magnet.  That would be (as 
described elsewhere) a basically different scheme because they're more 
"incremental encoders" and then you need a way to index it to zero.

Oddly, a cheap way might be to put a digital compass on the antenna, and 
then having a microcontroller turn that into voltage (or resistance) for 
the controller.

Adafruit has a three axis magnetometer for $5. 
https://www.adafruit.com/product/5579 - it has a I2C interface. Then how 
to get that data back to the shack. These days, I'd be thinking about 
WiFi with a Pi-Zero or a Arduino, but some sort of serial interface 
could also work.

Then, another microcontroller to turn it into a voltage.

You'd have to work out how to deal with "turn past 0 or 360" - with 
geared pots, the "0-360" range is the middle of the pot range, so you 
can get -10 degrees or 370 degrees.

Would a simple bang/bang rotator controller deal with that correctly?  I 
don't know.