auxilary O2 circuit pics please

brownington_bomber · 09-30-2009, 03:38 PM

I am setting up my v3.57 board through a megascott adapter and planned on running dual wideband setups. I know with megasquirt II I need to run my second O2 input into J5 and had planned to construct the O2 circuit on the proto area of the adapter as the v3.57 board has no proto area.

I have seen the diagrams on both DIY's page and the mega manual but would like to see a picture of someone's proto area where they have built this circuit. I'm running Innovative O2s so if you could point out how you wired in the 470 Ohm resistors that would also be helpful.

I know with the diagrams I should get what I am shooting for (and I think I do), but I would like to see a more visceral example to confirm. As always, your help is much appreciated in getting one more rolling spokesman on the road for Megasquirt!

Jon

huafist · 09-30-2009, 08:07 PM

I'd post mine, but it won't do you much good. I've got so many extra circuits in there you can't tell what's what without knowing what part you're looking for haha.

brownington_bomber · 09-30-2009, 11:29 PM

Yea, thats probably for the best. I'd hate to end up with a knock sensor circuit where an O2 should be... lol Thanks though.

Jon

rusty105 · 10-26-2009, 04:39 PM

I could post a pic of a 2nd coolant, and 2nd O2 circuit on a v3 PCB if that would help. It's a narrow band O2 so it wouldn't be much help for the resistor.

Rusty

brownington_bomber · 10-26-2009, 11:59 PM

That would be great. Thank you. Does the narrow band circuit just use the two caps without the resistor?

rusty105 · 10-27-2009, 12:42 PM

Quote:

Originally Posted by brownington_bomber

That would be great. Thank you. Does the narrow band circuit just use the two caps without the resistor?

I'll get some pics up tonight, or first thing tomorrow morning.
The O2 circuit on the V3 boards is R10, R11, C10 fed into JS5 (ADC6) Which circuit are you talking about 2 caps and a resistor? (wideband setup?)
Rusty

brownington_bomber · 10-28-2009, 01:45 AM

I thought I was, but now I seem to second guess as to whether the diagram was ever explicite about whether or not it was for wide or narrow band. The one I am referencing is under DIYautotune's page under common modifications and also under adding a second O2 sensor on the megamanual. I appreciate you getting the pictures as I don't seem to have translated very well from paper to actual board.

Matt Cramer · 10-28-2009, 10:13 AM

The diagram works for either one.

rusty105 · 10-28-2009, 12:42 PM

Jon,

I have the pictures, but it appears i can't attach them in a post??? I will have to host them somewhere quick, but would rather attach them in the post.

Rusty

rusty105 · 10-29-2009, 08:14 PM

OK

Here it is

Ok, now the circuit just above the 'Area' is the O2 circuit, the 2 header pins just to the left are O2 circuit in, and out to ADC. The circuit just above that is the temp sensor circuit (coolant, oil).

You can reduce the schematic to a 'point to point' type of wiring under the circuit board

If you have more questions, let me know

Rusty

I need to dust the PCB, the camera really shows the dirt.

brownington_bomber · 10-30-2009, 12:31 AM

Thank you sir! It helps to see it layed out. Did you use header pins for an ability to remove the input and output, or is that the general construction method? Thanks again, as its a relief to see my inclinations were roughly on the right track. Cheers.

Jon

rusty105 · 10-30-2009, 11:17 AM

Quote:

Originally Posted by brownington_bomber

Thank you sir! It helps to see it layed out. Did you use header pins for an ability to remove the input and output, or is that the general construction method? Thanks again, as its a relief to see my inclinations were roughly on the right track. Cheers.

Jon

I used the header pins to be able to switch things arround easily. I have two jumper wires connected to two of the spare db37 pins (not the ones for CAN bus) I am not 100% sure where these would be on a 3.57 PCB, but I am sure they are there. One end is cut off and soldered to the board, the other end still has the female header connector. I have two of them, one oil temp, one O2 sensor. (for now). I then have two single pin headers in the proto area that connect to JS4 or 5, which go to ADC7 or 8. Then I have two header pins for each circuit, one in, and one out. I just wish I used two pins together, instead of two individual pins for the in and out, that way they would both be straight, and not have one lean one way or the other.
If you have any more questions, feel free to ask away.
Rusty

brownington_bomber · 10-30-2009, 04:21 PM

I've noticed the mega manual's diagram shows a zener diode in the circuit while the DIY diagram excludes this. Does anyone know if this diode is neccessary, or if it has become superfalous? Thanks again, guys, for the replies.

Jon

rusty105 · 10-30-2009, 04:36 PM

Quote:

Originally Posted by brownington_bomber

I've noticed the mega manual's diagram shows a zener diode in the circuit while the DIY diagram excludes this. Does anyone know if this diode is neccessary, or if it has become superfalous? Thanks again, guys, for the replies.

Jon

Zenner? Where? What component number? (D3, as an example) On what schematic? The circuit I built is the O2 circuit for the v3 PCB, (R10, R11, C10) It shows the same for the 3.57 schematics. Do you have a link for the diagrams?

Rusty

brownington_bomber · 10-30-2009, 09:33 PM

There is no component number on the diagram, but its a 5.1v zener. The diagram is off the msextra hardware manual (it doesn't let me put up links or I would. Its the only diagram I've seen that list it and its shown in parallel with the .22uF cap. I'm not worried about not running it as you and others have obviously proven that the setup without works and I trust the legitimacy of DIYautotune's info; I'm just curious if there is (or was at one point) a reason they listed it. Thanks.

Jon

Matt Cramer · 11-02-2009, 09:15 AM

The zener was part of an earlier design, but it turned out to be unnecessary, and it distorted readings when the voltage got close to 5 volts. So Bowling & Grippo removed it from most of the sensor inputs.

brownington_bomber · 11-05-2009, 12:56 AM

I thought I would update. I put together the circuit and will get some pics up in the next day or two for some final confirmation and some resolution to those that helped out. I could have ran a bit different placement for shorter leads, but as I'm doing two of these (one for my brother), the next can be a bit improved. Thanks again guys. Cheers!

Jon

rusty105 · 11-13-2009, 11:01 PM

How did it go?

Rusty

brownington_bomber · 11-15-2009, 09:19 PM

Sorry I've delayed in getting these up. I have been knee deep in a customers CJ-7 project.

As far as my proto area, I hope the pics are somewhat evident. Unfortunately the digital camera I am using has no macro setting so getting any closer would have just gotten blurry. I put my 470 ohm resistor on the board for the input from the LC-1 O2. To the side of the O2 circuit, I ran my first O2 to the proto area for a solid place to mount its input resistor.

If this looks scary bad, or if you need some clarification let me know and I'll try to explain. Also on my photobucket there is three more; I just wanted to use as little space as neccessary on the Corral. Thanks again.

....

Ok, on trying to post these I read the FAQ on the Corral and it said to use the image URL with the bracket img bracket and then after with the backslash added, but upon trying to do this, it has informed me that I have not been here long enough to post links to outside websites. If there is a better method for us newer guys, please let me know, otherwise PM me and I can give you a link to my photobucket. Cheers.

Jon