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An inclinometer by Georg DF1SR and Bogdan SQ6EDU

I’ve often wanted to find a better solution for elevation. My own solution with a SCA61T works fine but now George and Bogdan have come up with a very nice encoder for this purpose. It uses a 15 bit 3 axis accelerometer (LIS3LV02DL) queried by an ARM microcontroller (STM32F). The STM32F interprets the data from the accelerometer and provides a 12 bit interface that simulates the chip inside the HH-12 (AS5045).

I have a preliminary version of the new encoder and I am very impressed. It operates very nicely as a direct substitute for the HH-12. The real advantage is that it is only necessary to clamp it to the boom of an antenna - no fancy axles. George says it has 0.1 degree accuracy which is very impressive.

The interface clocks a little slower than I used for the HH-12 so I have created a new  piece of software to burn into the PIC16F628A. This is called HH-12inc.hex. The software is essentially the same with an increased period for the clock.

The photo shows the working inclinometer operating on my prototyping beam controller. The reading of 89.9 degrees suggests my bench is quite level. Note the “0” is not significant, ignore it. Also my proto controller has currently sacrificed its clock chip for another project which explains the position of the moon as 0.00 etc. Georg will make further details available in the near future. See QRZ.com for Georg’s email.