Rotator control 1216L A/D error

[vaidis]

Hello,
rotator control unit 1216L have a big A/D converter reading error, if you watch your web page, it's about +- 4 degrees. Disconnecting rotator potentiometer from RCU input not solve the problem,  I try to connect accumulator 6V to input, the same result, very big reading error. Without input voltage, "LAST A/D" changes from 11 to 14.
How to solve this problem

[Jan (Microbit)]

I am not sure I understand what you mean here, could it be that you mean for a specific voltage level you get very different "last a/d values"?

[ON4AOI]

Jan,
what he is trying to explain is that the input for the A/D converter is not stable.
I have the same problem , even with a professional PS set on 5Volt for example
the LAST A/D readout will be different everytime you open the webpage.
Resulting in different direction for the same value.

Guy ON4AOI 

[Jan (Microbit)]

I would expect different values, but I would not expect them to differ so much that you get different directions. What is min and max values if you use your professional PS 5 Volt?

[ON4AOI]

About 3 to 4 units Jan

[vaidis]

After software upgrade to 1.23 version, A/D converter problem still the same. With 12V rotator system I get +-2 degrees error.
9.82V input: Last A/D: 617 - 621, direction changes from 328 to 359 degrees  ( seting values: 300 deg. value 565, 359 deg. value 674 ).  On 300 degrees position, values changes from 298 to 301. Input voltage stable.

vaidis

[Jan (Microbit)]

After software upgrade to 1.23 version, A/D converter problem still the same. With 12V rotator system I get +-2 degrees error.
9.82V input: Last A/D: 617 - 621, direction changes from 328 to 359 degrees  ( seting values: 300 deg. value 565, 359 deg. value 674 ).  On 300 degrees position, values changes from 298 to 301. Input voltage stable.

vaidis

1.23 did not contain any improvements regarding this, so no change compared to previous versions is expected. Did you really mean that A/D values 617-621 caused direction changes 328 to 359? Maybe you mean 358 to 359?

[Jan (Microbit)]

Bringing up this a bit out-dated thread again. The behaviour seen in this thread may be caused by the fact that the accuracy of the A/D is 8 bits while it allows reading out up to 16 bits. We have so far set-up the A/D for 10 bits and so a constant voltage may give a small variation in the A/D readings due to what Maxim calls "random noise". How much that small variation means in degrees will then depend on the maximum output voltage from the rotator, the lower voltage the higher the error become. The A/D allows the use of two different voltage ranges, 0-2.55 V and 0-5.10 V. We have so far used the 0-5.10 V range and so if the maximum output voltage is lower than that the error will also increase.

In a coming new release of the firmware we have added the possibility of changing both the range and the resolution between 8-15 bits. That will make it much easier to adjust for rotators with low maximum output voltage, though the rotators with 1.2V as maximum output will most likely still suffer from loss of precision.

[ON4AOI]

On screen it jumps time to time but
when you set the direction either via presets
or typing in the drgrees , its no more then 3 degrees off for a
modified YAESU G450C (12bits A/D setting and  0-2.55V)

Guy ON4AOI

[JI1HNC]

Hi

My 1216L-5 has been working fine for 8 months, however, A/D values
jumped randomely form time to time recently.

System info shows "HW >= 5, FW 5" and the LED blinks once a second
properly. G-1000 pot voltage is mooving smoothly from 0V to 4.6V.

Your assistance would be very welcome.

Regards,

AKira

[sm2o]

Hi
I guess it's a bad connection or moisture somewhere in the cabling or pot if it randomly gives big errors.

73 de mile

[JI1HNC]

Mike-san,

Thank you very much for your advice. I released all wires to 1216L and re-connected them
but the situation remains unchanged.
Worse, A/D value does not change while pot voltage is moving.
When I restart webswich1216H, A/D value changes. (randomely but not always)

firmware version: HAM4.17
pot voltage is measured on the printed circuit of 1216L

Further advice will be very much appreciated.

Akira

[sm2o]

It's difficult to say whats wrong and we have never got one back for repair before so I have no guess. Maybe it's hit by a lightning storm ?, You can remove the pcb and send it to us in a padded envelope. State value = 0 for the customs.

73 de mike

[JI1HNC]

Mike-san,

Thank you for your reply, spending weekend spare time.
No lightning atack has been recognized, but I will send it to Microbit
for investigation.

Regards,

Akira

[JI1HNC]

Mike-san;

Have you found any malfunction in my 1216L ?
Further advice would be appreciated.

Regards,

Akira
JI1HNC