DIY digital temp gauges
#1
DIY digital temp gauges
I've always wanted dual digital gauges, but not for $300 (Spa brand):
If someone can find an inexpensive (~15) LCD backlit green voltmeter panel gauge of the right size, I will design a circuit to read off of the factory water temp signal, and off of a $1 oil temp thermistor so it will read oil and water temps. An EGT circuit is easy too.
The panel meters have to be small enough to stack 2 vertically by 3 wide in the miata's panel below the stereo.
Here is what I mean by panel voltmeters:
However in this example (a) it has no backlight and (b) it is too tall to stack 2 vertically.
With small enough meters, one could replace the factory temp gauge in the dash with dual oil and water temp too....
FWIW backlit LCD is better than LED because the latter is hard to read in sunlight.
If someone can find an inexpensive (~15) LCD backlit green voltmeter panel gauge of the right size, I will design a circuit to read off of the factory water temp signal, and off of a $1 oil temp thermistor so it will read oil and water temps. An EGT circuit is easy too.
The panel meters have to be small enough to stack 2 vertically by 3 wide in the miata's panel below the stereo.
Here is what I mean by panel voltmeters:
However in this example (a) it has no backlight and (b) it is too tall to stack 2 vertically.
With small enough meters, one could replace the factory temp gauge in the dash with dual oil and water temp too....
FWIW backlit LCD is better than LED because the latter is hard to read in sunlight.
#4
2 Props,3 Dildos,& 1 Cat
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I had some panel voltmeters I converted to read Wideband 0-5V signals and turn them into AFR.
Jason: can you post up a schematic for the "share the sensor" circuit for water temp?
Jason: can you post up a schematic for the "share the sensor" circuit for water temp?
#8
Boost Czar
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http://www.diyautotune.com/tech_arti...alculation.htm
something like that. the body of the sensor is ground. I'm sure they are a generic sender you can pick up for a song. I dunno...
something like that. the body of the sensor is ground. I'm sure they are a generic sender you can pick up for a song. I dunno...
#15
mkturbo.com
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That I do not know, I just bought the 2 senders for now. When I am done with my engine build and have spare money I will pick up the gauges.
#18
2 of these stacked vertically would juuuust fit, but no backlight!
http://www.lumex.com/specs/LCD-S2X1C50TR.pdf
$3 at Digikey:
http://parts.digikey.com/1/parts/679...s2x1c50tr.html
That one is reflective.
Here's the "trans-reflective" version of the same thing:
http://search.digikey.com/scripts/Dk...ame=67-1798-ND
Trans-reflective means you can read it with ambient light, *and* you can also backlight 'em.
I just might buy some to play with it, see if I can add backlighting.
http://www.lumex.com/specs/LCD-S2X1C50TR.pdf
$3 at Digikey:
http://parts.digikey.com/1/parts/679...s2x1c50tr.html
That one is reflective.
Here's the "trans-reflective" version of the same thing:
http://search.digikey.com/scripts/Dk...ame=67-1798-ND
Trans-reflective means you can read it with ambient light, *and* you can also backlight 'em.
I just might buy some to play with it, see if I can add backlighting.
#19
Boost Pope
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Very nice looking unit, and the backlight modules are pretty cheap as well.
One thing that occurs to me about the specific units you posted, at least in a temperature-reading application, is that they can only display a maximum reading of 199°. Well, actually that's not true; they could display a maximum value of 511°, but only if you enjoy doing hex-to-decimal conversion in your head in realtime.
They do have three-digit units which fit in essentially the same outline, though the characters are much smaller and are spaced out a great deal more. http://search.digikey.com/scripts/Dk...rds=67-1799-ND
One thing that occurs to me about the specific units you posted, at least in a temperature-reading application, is that they can only display a maximum reading of 199°. Well, actually that's not true; they could display a maximum value of 511°, but only if you enjoy doing hex-to-decimal conversion in your head in realtime.
They do have three-digit units which fit in essentially the same outline, though the characters are much smaller and are spaced out a great deal more. http://search.digikey.com/scripts/Dk...rds=67-1799-ND
#20
I will display in Celsius.
Remembering "100*C" = boiling and "120*C" = "freaking hot" is easy.
Here's a 128x64 dot matrix, serial comm, includes the backlight. Perhaps it can be shoehorned in the gauge cluster:
http://www.sparkfun.com/products/710
Dimensions:
Overall: 75 x 53 mm
Viewable area: 55 x 27.5 mm
Of course only a portion of it will show, but that's enough to display oil and water temps
And they have LCD's galore:
http://www.sparkfun.com/categories/148
Remembering "100*C" = boiling and "120*C" = "freaking hot" is easy.
Here's a 128x64 dot matrix, serial comm, includes the backlight. Perhaps it can be shoehorned in the gauge cluster:
http://www.sparkfun.com/products/710
Dimensions:
Overall: 75 x 53 mm
Viewable area: 55 x 27.5 mm
Of course only a portion of it will show, but that's enough to display oil and water temps
And they have LCD's galore:
http://www.sparkfun.com/categories/148