GS indicator circuit-Jim Weir?

[Fonz]

This question is mainly aimed at Jim Weir, but others are more than welcome
to give their 2c.
With the aero-lectrics column in kitplanes, a GS tester has just been
completed.
My question. How hard would it be to make a GS indicator, with say LEDs
instead of lines and needles. For example, when going down the glideslide,
needles centred, you get a Green led in the centre, diverge and get yellow,
really off and get red, the universal warning. Rotary encoder with 7
segment leds for OBS. How hard would this project be? (considering the
grand scale of the test unit just completed). Obviously not for Primary
use, but as a tester for radios, and possibly a back-up unit.
Thanks.
Just a thought.
Rob
Australia.

[Scott]

Should be easy enough using op-amp comparators with resistors setting up
a 10 or 20 step voltage divider as a reference. For example, if the
voltage swing that drives an analog meter goes from 0 volts for the
needle at its full down position (high of GS) to 5 volts at its upper
most swing (low of GS), the comparators compare the voltage used to move
the needle and light a corresponding LED (at 2.5 volts, or half-scale,
the green LED would be lit)...Terra produced just such a radio back in
the 80s...I think it was called the Tri-Nav C...

Scott


Fonz wrote:

> This question is mainly aimed at Jim Weir, but others are more than welcome
> to give their 2c.
> With the aero-lectrics column in kitplanes, a GS tester has just been
> completed.
> My question. How hard would it be to make a GS indicator, with say LEDs
> instead of lines and needles. For example, when going down the glideslide,
> needles centred, you get a Green led in the centre, diverge and get yellow,
> really off and get red, the universal warning. Rotary encoder with 7
> segment leds for OBS. How hard would this project be? (considering the
> grand scale of the test unit just completed). Obviously not for Primary
> use, but as a tester for radios, and possibly a back-up unit.
> Thanks.
> Just a thought.
> Rob
> Australia.
>
>

[RST Engineering]

I'd probably use a 9-step system. Green in the center, then orange, yellow,
blue, and red going up and down. What does the rotary encoder do?

Jim


"Scott" > wrote in message
.. .
> Should be easy enough using op-amp comparators with resistors setting up a
> 10 or 20 step voltage divider as a reference. For example, if the voltage
> swing that drives an analog meter goes from 0 volts for the needle at its
> full down position (high of GS) to 5 volts at its upper most swing (low of
> GS), the comparators compare the voltage used to move the needle and light
> a corresponding LED (at 2.5 volts, or half-scale, the green LED would be
> lit)...Terra produced just such a radio back in the 80s...I think it was
> called the Tri-Nav C...
>
> Scott
>
>
> Fonz wrote:
>
>> This question is mainly aimed at Jim Weir, but others are more than
>> welcome to give their 2c.
>> With the aero-lectrics column in kitplanes, a GS tester has just been
>> completed.
>> My question. How hard would it be to make a GS indicator, with say LEDs
>> instead of lines and needles. For example, when going down the
>> glideslide, needles centred, you get a Green led in the centre, diverge
>> and get yellow, really off and get red, the universal warning. Rotary
>> encoder with 7 segment leds for OBS. How hard would this project be?
>> (considering the grand scale of the test unit just completed). Obviously
>> not for Primary use, but as a tester for radios, and possibly a back-up
>> unit.
>> Thanks.
>> Just a thought.
>> Rob
>> Australia.

[Denny]

Been done... TKM MX-300 series... No longer in production... Both the
GS and the VOR needle are leds... I have one in my PA-23... Works just
fine... Takes all of 30 seconds to get used to it...

denny

[Fonz]

The rotary encoder would be used, with some sort of position feedback to
change the obs setting if in the VOR mode, in the GS mode it does nothing.
Your thoughts on the 9 step system are exactly what I was thinking of, but
you were able to explain it clearly.
Thoughts on how it would work?

"RST Engineering" > wrote in message
.. .
> I'd probably use a 9-step system. Green in the center, then orange,
> yellow, blue, and red going up and down. What does the rotary encoder do?
>
> Jim
>
>
> "Scott" > wrote in message
> .. .
>> Should be easy enough using op-amp comparators with resistors setting up
>> a 10 or 20 step voltage divider as a reference. For example, if the
>> voltage swing that drives an analog meter goes from 0 volts for the
>> needle at its full down position (high of GS) to 5 volts at its upper
>> most swing (low of GS), the comparators compare the voltage used to move
>> the needle and light a corresponding LED (at 2.5 volts, or half-scale,
>> the green LED would be lit)...Terra produced just such a radio back in
>> the 80s...I think it was called the Tri-Nav C...
>>
>> Scott
>>
>>
>> Fonz wrote:
>>
>>> This question is mainly aimed at Jim Weir, but others are more than
>>> welcome to give their 2c.
>>> With the aero-lectrics column in kitplanes, a GS tester has just been
>>> completed.
>>> My question. How hard would it be to make a GS indicator, with say LEDs
>>> instead of lines and needles. For example, when going down the
>>> glideslide, needles centred, you get a Green led in the centre, diverge
>>> and get yellow, really off and get red, the universal warning. Rotary
>>> encoder with 7 segment leds for OBS. How hard would this project be?
>>> (considering the grand scale of the test unit just completed).
>>> Obviously not for Primary use, but as a tester for radios, and possibly
>>> a back-up unit.
>>> Thanks.
>>> Just a thought.
>>> Rob
>>> Australia.
>
>