[Moon-net] Lidl level

[Edward R. Cole]

At 06:33 PM 1/16/2007 -0900, Edward R. Cole wrote:
>
>At 04:59 PM 1/16/2007 +0100, Oene Spanjer wrote:
>>
>>Hello Edward,
>>
>>For overcome the long cable problem try using the noise rejection tric on
>>the page of PA3FPQ http://members.chello.nl/j.swienink1/elevation.html
>>I myself had very unstable readout with a cable length of abt 30 meters,
>>but after that it is doing perfect job!!
>>Gl to you and hopefully we make a qso one day !!!
>>
>>73 Oene
>>PA3CWN
>
>Oene,
>
>Thanks for the tip.  I had read of folks using the swinink level but only
>reference was sources in Europe so when the Memsic unit was suggested I
>took a chance and ordered two (one for 2m and other for 23cm eme antennas).
>
>Getting inside the memsic unit is not easy as they are cemented inside a
>plastic enclosure.  I found using a razor knife I could remove the back OK,
>but still may make accessing the elevation sensor leads difficult.  Also I
>have no idea on circuit lead identification.  I did measure the dc voltage
>on the indicator so do not think there is significant drop there.  But
>noise may be a factor.  I am using shielded cable anticipating noise
>issues.  I did use a 10 uF electrolytic to stiffen the supply voltage, but
>did not bypass with 0.1 uF caps.  Supply voltage is 9v but all operating
>levels are at 5v.
>
>I'm not at a point of giving up on these units.  I just was running out of
>good wx to get my 2m-eme array back in service so decided not delay raising
>it because of the elevation indicator.  I use actuator arms for elevation
>so calibrated the digital postion indicator for a look-up list for now.
>Having real-time elevation readout someday would be nice.
>73's,
>Ed - KL7UW  

I guess I didn't look at the Tips webpage close enough.  It shows the lead
layout and Indentification on the memsic sensor.  I got out one of my
memsic units to look at it and access will not be a problem as the sensor
is exposed.  There are two very small eyelets on terminals 4 (Vda analog
supply) and 8 (Vdd digital supply).  0805 chip caps might be used at the
eyelets to the ground plane by scratching off some green paint.  It will
require close work with magnifier.  Since the memsic Demo board provides
power to both terminals I do not think I would bridge them with a 10-ohm
resistor.

If successful with this fix, I will write up a short article on using this
angle encoder for antenna elevation display to be place on my webpage under
"Tech Topics".
73's,
Ed - KL7UW  
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