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[HiProfile]

Just curious, would anyone want info to build a $10 circuit to view their wideband's AFR's? I stumbled across one trying to find a cheap LED bar graph, and I got this idea. The only problem is the old skool widebands w/o linear outputs won't get a linear representation, and have to adjust it a lot more to get right. FYI you can use multiple chips, and each chip used can drive 10 LED's. I'm sure if you could convert the tach signal to DC voltage, you could also do something like the lude/s2k bar graph tach.


http://www.national.com/mpf/LM/LM3914.html

[92CXyD]

Just curious, would anyone want info to build a $10 circuit to view their wideband's AFR's? I stumbled across one trying to find a cheap LED bar graph, and I got this idea. The only problem is the old skool widebands w/o linear outputs won't get a linear representation, and have to adjust it a lot more to get right. FYI you can use multiple chips, and each chip used can drive 10 LED's. I'm sure if you could convert the tach signal to DC voltage, you could also do something like the lude/s2k bar graph tach.


http://www.national.com/mpf/LM/LM3914.html

Yes yes yes,  Hi, Si, Wi, Da, Ja, yeah ;D :yes:

[patsmx5]

My LC-1 has configurable outputs. I just set one of the outputs to 10-20 AFR 1-2V. Then bought a 5V DC display off ebay for like 8 shipped. Hook'd it up and got this:

[HiProfile]

Any links to your display? That looks liek a good cheap solution.

I'm guessing its very similar to this, as it appears you adjusted the decimal spot.
http://cgi.ebay.com/Universal-Digital-LED-Volt-Current-voltage-panel-meter_W0QQitemZ200324147749QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item200324147749&_trksid=p3286.c0.m14&_trkparms=72%3A1240%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A0%7C293%3A1%7C294%3A50

THe issues I see with that display are speed and size. Most only show 1-3 readings a second, while the chip I linked to would move the LED graph in real time. You are also limited to where you put it, while the LED bar could be put virtually anywhere. I was also thinking of using various red/yellow/green LED's for various ranges like the crap narrowband gauges.

[92CXyD]

Try these : http://www.futurlec.com/Panel_Meters.shtml

[patsmx5]

Any links to your display? That looks liek a good cheap solution.

I'm guessing its very similar to this, as it appears you adjusted the decimal spot.
http://cgi.ebay.com/Universal-Digital-LED-Volt-Current-voltage-panel-meter_W0QQitemZ200324147749QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item200324147749&_trksid=p3286.c0.m14&_trkparms=72%3A1240%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A0%7C293%3A1%7C294%3A50

THe issues I see with that display are speed and size. Most only show 1-3 readings a second, while the chip I linked to would move the LED graph in real time. You are also limited to where you put it, while the LED bar could be put virtually anywhere. I was also thinking of using various red/yellow/green LED's for various ranges like the crap narrowband gauges.

That's the one I have, but I bought it from someone else. And mine was cheaper, like 10 or 12 shipped. Mine was setup to read 0-5V IIRC, but you can change that one up with the included resistors. Yeah I moved the decimal on mine for it to say 10-20 instead of 1-2. On mine, the reflash rate was too fast if anything. Probably 7 times a second, maybe 10. Definitely not too slow.

[marcj]

I found the display for 16 bucks shipped from a chingchong dealer. I can't tell if you can adjust the decimal placement.. what do you guys think?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=300302092773

[HiProfile]

Well it would simply display 1.00 to 2.00 AFR's if you can't adjust the decimal. It wouldn't be too hard to convert in your head.

I think I'll be getting one of those for my "tuning kit", since my O-Meter doesn't work half the time. If I'm lucky, I can get it repaired/replaced & sell it.

[walter]

Any links to your display? That looks liek a good cheap solution.

I'm guessing its very similar to this, as it appears you adjusted the decimal spot.
http://cgi.ebay.com/Universal-Digital-LED-Volt-Current-voltage-panel-meter_W0QQitemZ200324147749QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item200324147749&_trksid=p3286.c0.m14&_trkparms=72%3A1240%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A0%7C293%3A1%7C294%3A50

THe issues I see with that display are speed and size. Most only show 1-3 readings a second, while the chip I linked to would move the LED graph in real time. You are also limited to where you put it, while the LED bar could be put virtually anywhere. I was also thinking of using various red/yellow/green LED's for various ranges like the crap narrowband gauges.

That's the one I have, but I bought it from someone else. And mine was cheaper, like 10 or 12 shipped. Mine was setup to read 0-5V IIRC, but you can change that one up with the included resistors. Yeah I moved the decimal on mine for it to say 10-20 instead of 1-2. On mine, the reflash rate was too fast if anything. Probably 7 times a second, maybe 10. Definitely not too slow.

does i t works only with LC1 WB?

[92CXyD]

No it work with other WB O2 including bosch 17014's :yes:

[HiProfile]

I think he meant wideband controllers, not the sensor itself.

That all depends on the controller's output. If you can program the wideband output where 1v= 10:1 afr and 2v= 20:1 afr, it would work perfect. Otherwise you'll be stuck doing lots of conversions in your head. Obviously the LC-1 has programable outputs, and DIY's like techedge & 14point7 units do too. Many others have an oddball fixed non-linear output. For those only the 10-LED chip would work, but would be off in certain spots.

[marcj]

i think i'm going to get a techedge unit.. shit's fucking ballin and cheap with the currency exchange the way it is right now.

[HiProfile]

Same here, the DIY Techedge version (2Y) w/o sensor works out to $100/ea shipped if I get one for both cars. Its an updated version of a unit they've sold for years, has 3 analog inputs, RPM, and 3 thermocouple inputs. Then just ~$15 for a display like above...

FYI WBO2.com charges ~$80+shipping for a sensor, while Amazon has them for ~$50.

[92CXyD]

I go to my local parts store and by them for 50usd part # 17014

[Joseph Davis]

FYI, old school riceboy lightshow narrowband air-fuel meters work great for this.  A JAW could be set up to light the particular LEDs you want it to at a given AFR.