diy mpg gauge

[skewbe]

or it may need to be isolated with an op-amp/transistor, hmm is your metro vss magnetic?

[skewbe]

Also, are you auto or stick? I saw a sentance in the haynes that said the vss was in the trans on an auto, and thus it might be magnetic instead of a hard to throw off with a 10k resistor switch.

On a side note, the scangauge started working in the saturn again so I might have cause to work this more actively.

[mpmetro]

Originally Posted by skewbe

Also, are you auto or stick? I saw a sentance in the haynes that said the vss was in the trans on an auto, and thus it might be magnetic instead of a hard to throw off with a 10k resistor switch.

On a side note, the scangauge started working in the saturn again so I might have cause to work this more actively.

my 91 is a 5spd manual. But I dont worry about the CEL.

[sonyhome]

Wouldn't a CEL code risk sending your computer in open loop mode, wasting gas?

If you use like a cheapo 741 op-amp, might as well use it in comparator mode then with 2 potentiometers, gives you full insulation, but you'll need to wire a power supply, like a +5V or a +12V to it (or a battery?).

That would send a clean square wave to the headphones and tuning would be at the pots instead of the config file.

I need to find and spend some time to get a setup too to jump on the bandwagon...

[GasSavers_Doc]

I've got mpg.java to work but have not sure how wire anything to it yet. Trying to work out how to code Java so I can get an Oxygen sensor reading as well. Can this kind of app run off two sound cards so we have 4 channels.
Very Impressive work!!!

[skewbe]

Thanks Doc, I don't know about two sound cards without trying. It might be operating system dependant (i.e. you could do it under linux but not windows).

FYI, mpmetro did a good metro specific installation writeup: http://teamswift.net/viewtopic.php?p=255816#255816

[ami8i]

Hello skewbe,
thank you very much for developing and releasing the mpg monitor!
I came across this forum because I have looked for an item like the Super MID. I'd prefer a ?C DIY solution - but exploiting soundcard for such a gauge is very cool.

My problem ist my poor Hardware. What is the oldest possible Java release to get the mpg monitor running?
I tried jre-1_5_0_13-windows-i586-p-s.exe and jre-1_5_0_10-windows-i586-p-s.exe , both installations failed because my laptop does not provide the 'recomended' memory. I guess RAM is meant. There is enough free space on HDD.

The laptop is an old Toshiba Tecra, 133MHz, 16MB RAM, Win98SE.
I can't find any space/memory requirements for any Java release. This site seems to show all Java releases http://java.sun.com/products/archive/

I can't download & test all releases.

Thanks and Best regards from Austria
?Horst

[skewbe]

wow, 16mb, I did not anticipate that. It ran under windows 98 on my 133mhz laptop with 32mb and java version "1.5.0_06". I thought that would be pretty much lowest common denominator. I think if you can upgrade your memory you will be in business.

Here is a $25 48meg upgrade, search for NW2041U in your area or better yet a NW2042U (128 meg) if you want to keep that laptop in service,

http://cgi.ebay.com/TOSHIBA-NW2041U-...sid=p1638.m118

[FritzR]

hey skewbe

if the purpose of the diode it to keep the voltage to the soundcard uner .775 volts so the signal does not clip above 0 DBV, wouldn't it work as well to just make a voltage divider circut?

If the input impedence of the soundcard was 20K then use a 400K resistor to the input not grounded. That would be something like .5 volts to the sound card. You wouldn't need to worry about loading up the injector signal that way.

[rsxer63]

Does anyone know if this would work with a Nokia 770?