>     http://www.kpsec.freeuk.com/components/cmos.htm#4017
         >
         >     Get a couple of these CMOS 4020 and fool around with them
         >     until it works. Dividing by 13,333 by 64 (pin 4) will give
         >     about 208 Hz max. Put the square wave signal from the 555
         >     in on pin 10,  Take the signal out on pin 4, ground pin 11
         >     and leave all other pins unconnected. DigiKey or Mouser.
         >
         >     If it works tell Greg he owes me :)
         >
         >     ----------------------------------------------------------
         >
         >     Frequency  to analog 0 to 5 Volts Converter.
         >
         >     After you divide it down you can use one of the these and use
         >     the stock 0 to 5 volts analog BMA fuel gage inputs.
         >
         >     Paul Lamar ...No rotor no motor.

        Mark Steitle wrote:
         > Paul,
         > I'm not sure how to proceed here.  It appears that you have
        provided me
         > with two options.
         >
         > Option 1:  Use a 555 timer and feed the output into the 4020
    ripple
         > counter, and finally to the 2917.  This would make it so that
    I could
         > feed the signal from the 2917 into the 0-5v channels on the
    EFIS.
         >
         > Option 2:  Use the circuit shown in the KPsch.jpg attachment.  Is
        this
         > an IC that I can purchase, or would I need to build it from
    scratch?
         > Would this circuit handle the task all alone or does it need
        additional
         > hardware?
         >
         > Thanks,
         > Mark
         >

        As far as I can tell your current probes are putting out up to
    15 KHz
        square wave pulse frequency's. Not pulse widths. Too high a
        frequency for
        the BMA. So all you need do is feed that into 4020, divide it
    down by 64
        and then feed that into the BMA low frequency inputs. That is option
        one.

        Option two is add a frequency to analog voltage converter (the
    LM 2917)
        and then feed that into the regular BMA fuel quantity channels that
        require
        an analog voltage between zero and five volts.

        Both are very low cost IC's that can be purchased from Digikey or
        Mouser.
        DigiKey has 25,000 CD4020 in stock for $1.76 each :)


        The LM2917 replaces the KPsch.jpg. The KPsch.jpg is the same
    thing done
        with discrete transistors and a quad op amp.

        Check this out on the BMA forum with credit to me and see what
    they say.

        Paul Lamar ...No rotor no motor.

    Paul,
    Ok, now I get it.  I'll get some of each ordered and try them to see
    what works best/easiest and then post the results to the BMA list.  The
    new BMA EFIS uses an instrument module that has two capacitance
    channels, so this is not a problem for the late-comers.  Worth posting
    anyway as there are plenty of us early "Gold Box" owners still out
    there.  Appreciate your help.

    Thanks,
    Mark
    Lancair ES-20B, 15 hours

    Post it here too Mark. Might be of interest to other people
    using the same probes. By the way it is real easy
    to build your own probes using two one inch wide long strips of brass
    separated by nylon nuts and bolts. Takes about an hour or two.
    A 555 will handle the electronics.
    --
    Paul Lamar ...No rotor no motor.


Paul,

I agree.  The only hard part is the end fitting, but a fitting could
probably be purchased at Home Depot and modified to work.  Might have a
total of $5 in each probe.  I ordered the EI probes when I ordered the
kit and didn't know squat about capacitive fuel probes.  I guess that's
part of the "education and recreation" of building your own airplane.

By the way, it is a real thrill, while also a bit scary to be flying
around above the clouds in an "experimental" airplane that you put
together in your garage and which uses a car engine along with a whole
bunch of do-it-yourself parts.  You can't help but wonder if you did
everything correctly as one snafu could easily ruin your whole day.
With that said, I'm beginning to feel a bit more comfortable about the
whole experience now.   But give me a couple-hundred hours of
trouble-free flying and then ask me how I'm feeling.

Mark
15 hrs (and counting)

My mother told me never to fly anywhere unless I could see the ground :)

Things happen. Plan on it. I am not supposed to be saying that
on here but never the less always have a plan B.

Judging by what I have seen so far of your excellent installation
I think you have less to worry about than most.

BTW what are you seeing on the "cylinder head" temperature gages
so far? You are our only experimenter on those.

How is the muffler working out?