Cheap Ditigal Tack

Discussion in 'Instruments / Avionics / Electrical System' started by Pops, Oct 2, 2016.

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  1. Oct 2, 2016 #1

    Pops

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    Friend of mine in IA has been using this tack on his VW powered airplane and likes it. I made an aluminum plate to mount it in a 3 1/8" instrument hole. Also a bracket to mount the sensor behind the prop flange on my C-85 and Aircraft Spruce sells a cap to cover the tack drive on the accessory case of the engine. Range from 0--9999 rpm. Can be powered by the 12V electrical system or like my friend uses, a 9V battery mounted behind the panel. I hooked it up to a 9V battery for the picture. You will be saving almost a pound over the use of a mechanical tack and cable. Not counting the money. Price is $10.88 including shipping.
    http://www.ebay.com/itm/Blue-4-Digi...199067?hash=item1a11c3df5b:g:E6EAAOSwxH1UFwfB

    BTW-- Notice the use of an blue aluminum breather elbow on the Cont engine. Saved over 1/2 LB over the stock brass elbow.
     

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  2. Oct 2, 2016 #2

    Wanttaja

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    In cases where you don't have an electrical system, I'd recommend the "Tiny Tach." It's admittedly about six times as expensive as Pop's friend's solution, but it also doubles as an hour meter and you don't need to install a sensor (just wrap the sensor wire around a spark plug lead).
    [​IMG]
    Does have to be replaced every 5-7 years when the battery expires.

    http://www.bowersflybaby.com/tech/tach.html

    Ron Wanttaja
     
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  3. Oct 2, 2016 #3

    Pops

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    Yes, the Tiny-Tack is good. What I used on the SSSC. I used shielded ignition on the VW engine so I had to do as in the instructions and drill a 1/16 hole and run the sensing wire inside the mag cab and do the wrap.
    I like the much larger digital numbers on this tack. Also just mount a 9V battery holder somewhere and change the battery each year.
    BTW-- After 5 years the battery in my Tiny-Tack finally gave up the ghost. I dug in the potting in the rear and found the little 3 volt battery and solder wires to the contacts and ran to a 2 AA battery holder for 3 Volts and would change batteries each year. Have to take another set of 3V AA batteries with alligator clips and clip on the Tiny-Tack battery wires so I wouldn't lose power and lose the hours accumulated when you change batteries.


    The led Volt and Amp gauge in the picture of the instrument panel on the SSSC works very well and cost $15.
     

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  4. Oct 2, 2016 #4

    Wanttaja

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    I considered doing the same when my Tiny-Tach finally gave up the ghost after seven years. I kept the old one sitting around for some exploratory surgery along those lines.

    But... at 200 hours total time, the Tiny-Tach hourmeter starts displaying only the hours, not the minutes. In my case, replacement was a minor enough effort so I'll plan on replacing when the time comes again.

    Ron Wanttaja
     
  5. Oct 2, 2016 #5

    Wanttaja

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    You know, it strikes me that many of us probably have old smart phones lying around that still retain significant functionality. Wonder what it'd take to build the appropriate sensors and interfaces and mount the phone in the panel for a display head.....

    Ron "Ardunio here I come" Wanttaja
     
  6. Oct 2, 2016 #6

    Dana

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    I had Tiny Tachs on my paramotors but they would sometimes go wonky; I found that the similar tach from ENM was more reliable.

    If you replace a Tiny Tach or similar and lose the hours, you can put them back on by connecting it to a low voltage AC source (I forget the voltage exactly, probably 3-5V). It will show an rpm, just leave it connected overnight or for a few days until the hours are where you left off.

    Dana
     
  7. Oct 2, 2016 #7

    Pops

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    I have a grandson the is a computer nerd and works for a computer company. I am lucky to be able turn it off and on, maybe I need to get him involved, he knows all about "Ardunio".
     
  8. Oct 2, 2016 #8

    Wanttaja

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    Re: Cheap Ditigal Tach

    Yes, but: If you do that, you'll lose the minutes indication when the Tiny Tach hits 200 hours. I just made a note in the log.


    I'm on the verge of retirement and not unfamiliar with digital panels. I might tackle it when I'm no longer working.

    Ron Wanttaja
     
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  9. Oct 2, 2016 #9

    Dana

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    This from a man who built his own autopilot... :)

    Dana
     
  10. Oct 2, 2016 #10

    Pops

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    Heck, I don't know everything, my wife agrees with that. :)
     
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  11. Oct 3, 2016 #11

    litespeed

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    Speaking of Arduino and instruments....


    In our local flight rag is this article on a $130 home made EFIS.

    Looks a great idea and will follow progress. View attachment efis homebuilt.pdf

    Add a nicer box or paint black. Even go expensive and get a colour screen.

    I love the idea.

    Could also have all the outputs going to a tablet.
     
  12. Oct 3, 2016 #12

    litespeed

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  13. Oct 4, 2016 #13

    N8053H

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    There is a reset button on the tiny tach. I had mine freeze or the screen froze. I hit the reset button and all was good. It does reset the hr meter though. This reset button is located right next to the part you push marked select. Its to the right of this select button. You must remove the plastic cover. I used a razor blade. Peel this cover up and you will see what looks like a rubber plug. Stick a really small screwdriver into that and you will push this reset button. Reattach the plastic cover and all is good. My plastic cover stuck right back on.

    Tony
     
  14. Oct 4, 2016 #14

    Pops

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    Just realized I spelled Digital wrong on the thread heading. What do you know that was a first :)
     
  15. Oct 5, 2016 #15

    clanon

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    Using one of these to count Prop RPM with a HDD magnet on the pulley.



    975-MLC2694964931_052012-O.jpg
     
  16. Oct 5, 2016 #16

    bmcj

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    Oh, so you were asking about a "digital" tach... well, then just ignore everything we have said up to this point because we were talking about "ditigal" tachs. :gig:

    At least you didn't write digital TACK... I have a hard time picturing a horse outfitted with modern digital avionics.
     
  17. Oct 5, 2016 #17

    Hot Wings

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    Imagine no more :gig:

    http://seaverhorse.com/
     
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  18. Oct 5, 2016 #18

    Wanttaja

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    C'mon now...he spelled "Cheap" right, which proves he's really a pilot......

    Ron Wanttaja
     
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  19. Oct 5, 2016 #19

    Pops

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    Yeah, thanks for standing up for me. I think :)
     
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