J.F.Drew © 2000-2013
The encoders HH-05 and HH-12 look identical except for the label.
They may be purchased from:
Ready made AS5040 and AS5045 encoders are manufactured by Georg, DF1SR ex DD0SB in south Germany. They are the HH-05 (10bit) and the HH-12 (12 bit). Both units are very nicely made and the size of a 'standard' potentiometer. I understand these cost between Euro 20-30 and save a huge amount of work giving you more time to work on the antennas or other interesting things.
For European amateurs the HH-05 or HH-12 from DF1SR may be an easier option than the MA3-P12 if freight from US-Digital is an issue.
Georg has sent me units for testing and I am happy to report that both the HH-05 and the HH-12 interface to the AZ/EL unit without difficulty.
I cannot test the actual lineal accuracy through an absence of quality test equipment. The HH-05 provides a theoretical 0.35 degree resolution. Averaging in the shack unit will allow readout to 0.1, but this should be used as a guide only. AustriaMicrosystems specifications for the AS5040 claim +/- 0.5 degree if the devices are constructed to their specifications.
Now that I have tested the HH-12 I am impressed with the steadiness of the 12 bit display without averaging and would recommend this device to you. As with the HH-05 I am unable to check the linearity over 360 degrees. It would certainly be at the top of my list for convenience and readout. Linearity is a consequence of the placement of the AS5040/45 chip in the device and unless individually adjusted will never be perfect.
One advantage of the HH-05/12 is that my software is able to access the actual bit values coming out of the AS5040/AS5045, whereas in the MA3-P12 the device converts the value to PWM (possibly from an AS5045) which I then reconvert to a number. A conversion that will increase the likelihood of errors.
HH-05 burn the standard AS5040 code into the 16F628. For the HH-12 burn the standard AS5045 code into the 16F628. See downloads below.
Another source of encoders are the Megatron series also manufactured in Germany. Their encoders will work with my AZ/EL board having been used by at least one European builder. http://www.megatron.de/export/Contacless__analog_Sensors/contacless__analog_sensors.html
The MAB25 (10 bit), MAB25A (10/12 bit) and MAB36A (12 bit) seem to be good choices. I do not know of anyone using the MAB36A, it looks nicely made but cost may be an issue. You will need to do your own research on these but if they use the AS5040/45 then my software should work. Walter ON4BCB in Belgium has stocks of MAB25 (12 bit) for 52 Euros.
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|WTI-1 Yaesu remote|
|Beam controller features|
|Optical 16 bit encoder|
|Optical encoder SEI|
|PWM for speed control|
|Record and playback|
|RD Contest logger|