Tach Attack

On Fri, 07 Aug 2009 21:52:49 -0700, Ron Wanttaja
wrote:


Finally, I noticed the "Tiny Tach" on the Aircraft Spruce web page.
Seemed pretty good...got its signal by wrapping a wire around a spark
plug cable. From the description, I wasn't completely sure which model
to buy. But when I went to the company's web page, I found they had a
universal "Commercial" model that also updated faster than the standard
units.

http://www.tinytach.com/tinytach/commercial.php

Only $65, so I went ahead and ordered one. It had both a tach function
as well as an hourmeter and two service timers. It didn't need ANY
other connection other than to wrap the sensor wire around a spark plug
cable. It has a built-in battery.


it is indeed a pity that tinytach cant be given the hint that a
replaceable lithium battery would see an aviation market open up for
them. two lithium batteries so that they can be replaced individually
without loss of power would seem a simple mod to make the tach really
useful.
my hp calculators have used the two battery idea for ages.(ever since
I bought them :-) )

Stealth Pilot

Stealth Pilot wrote:
On Fri, 07 Aug 2009 21:52:49 -0700, Ron Wanttaja
wrote:

it is indeed a pity that tinytach cant be given the hint that a
replaceable lithium battery would see an aviation market open up for
them. two lithium batteries so that they can be replaced individually
without loss of power would seem a simple mod to make the tach really
useful.

They're losing the vast aviation market? :-)

From what I can see, the product is mostly aimed at the industrial
engine market, especially rental equipment. They know it's being used
on aircraft engines, but I suspect the number of actual installations in
airplanes is pretty small. Probably mostly in the ultralight world,
since anything with a Lycoming or Continental is already going to have a
tach drive.

As far as the non-replaceability of the battery, we'll see when the time
comes. The case is sealed plastic, so it should be possible to cut it
open. If nothing else, adding an external pack for a battery shouldn't
be tough.

It looks like Tiny Tach did, in fact, recently upgrade its commercial
tach from using external power to using solely the internal battery.
The version of their installation instruction that's online shows a
battery connection....

http://www.tinytach.com/tinytach/ima...structions.pdf

When I ordered the tach, I thought I'd have to supply power to it.
Since I thought I'd have to deliver power to the meter, I figured I'd
add a small voltmeter as well, since my voltmeter is a short-arc analog
gauge mounted just above the floor (tough to read).

I ordered the Martel Tools QM-100V....

http://www.martelmeters.com/pdf/QM_100V.pdf

....and this is one slick device. Self-contained LCD voltmeter in a
package the size of two postage stamps, less than a quarter inch thick,
surface mounts using a 7/32" stud on the back of the package. Didn't
use it, since the tach didn't need power after all, but I'll probably
add it the next time I rework the power.

Ron Wanttaja

Gee Ron,

Your on a slippery slope. Digital displays and already planning your
next electrical upgrade! Could be evidence of that dreaded
psychological disorder known as Airventure Syndrome. We'll keep an
eye out for the major symptoms, obsessive urges to install IFR glass
panels, researching the installation of autopilot systems and weather
radar, and the most serious sympton requiring medication a small
little black box that costs more than your last house.

There is only one cure. Quick, rush to the airport and throw that
generator and starter into the bush, recycle the battery, and strip
all that tangled wire. Think back to the days when your electrical
system was 2 wires to a switch. There is hope still for a complete
recovery! ;-)

Bob

canuck_bob wrote:
Think back to the days when your electrical
system was 2 wires to a switch. ;-)

Bob


And some of us STILL do!

Scott
Corben Junior Ace
We don't need no steeenkin' electrical system

Scott a écrit:

Think back to the days when your electrical
system was 2 wires to a switch. ;-)

but now, electrical system may be more reliable. I read my old
continental engine health on an EIS 4000.
For my tach, I use two magnet on the flywheel, a reed contact and two
wires.

You know small continental d'nt have flywheel but a french guy make a
conversion for A65 with kubota permanent magnet alternator and
automotive starter. This kit may fit O200 too.
http://mdlaurent.free.fr/

I also use the magnets for CDI electronic ignition. no more magnetos,
no more cable for tach, no more copper tube for oil pressure...

By
--
« Si tous les poètes voulaient se donner la main, ils toucheraient enfin
des doigts d'auteur! »
Philippe Vessaire Ò¿Ó¬

Philippe wrote:
....
I also use the magnets for CDI electronic ignition. no more magnetos,
no more cable for tach, no more copper tube for oil pressure...

By

Not sure if this is what you mean, but a few high energy magnets
spinning on a plate do a great job producing pulses in a few coils
spaced close to the spinning magnets.

Seems like you could easily arrange two sets of coils to provide a
double source for a CD ignition, as well as timing it....
Or perhaps more compact, a source (if rectified and smoothed)
for one of those electronic ignition modules that fit inside the car
distributor, these days....

Either way that really amounts to a magneto I suppose - but so few
components, and double redundant so no battery would be involved.....

Brian W

"brian whatcott" wrote in message
...
Philippe wrote:
...
I also use the magnets for CDI electronic ignition. no more magnetos,
no more cable for tach, no more copper tube for oil pressure... By

Not sure if this is what you mean, but a few high energy magnets spinning
on a plate do a great job producing pulses in a few coils spaced close to
the spinning magnets.

Seems like you could easily arrange two sets of coils to provide a double
source for a CD ignition, as well as timing it....
Or perhaps more compact, a source (if rectified and smoothed)
for one of those electronic ignition modules that fit inside the car
distributor, these days....

Either way that really amounts to a magneto I suppose - but so few
components, and double redundant so no battery would be involved.....

Brian W

I admit that I don't recall who manufactures and sells them; but I seem to
recall that Steve Wittman used a "self sufficient distributor" fitting that
description, as part of his V8 conversion for the Tailwind, at least 25
years ago.

Peter

brian whatcott a écrit:

I also use the magnets for CDI electronic ignition. no more magnetos,
no more cable for tach, no more copper tube for oil pressure...

By

Not sure if this is what you mean, but a few high energy magnets
spinning on a plate do a great job producing pulses in a few coils
spaced close to the spinning magnets.

I have two simple magnets one north face and the other south face glue
at 0° and 180°.
The sensor is one AH287 and I use two automotive CDI boxes as power
stage for ignition #2.
I use one distributorless box from M&W ignition for #1.

For the electric wiring, I copy the following schematic:
http://www.jodel.com/index.asp?p=potezwiring&engines

My electronics devices are in the the point and distributor ignition
place.
In fact, I built 2 distributorless ignittions like today cars but
still have fix timing.

The wish list is one microcontroler for variable timing.

No way to built a small generator with my magnets. A batteryless
ignition like Jabiru require more start energy than my ignition.



By
--
« Si tous les poètes voulaient se donner la main, ils toucheraient enfin
des doigts d'auteur! »
Philippe Vessaire Ò¿Ó¬

canuck_bob wrote:
Gee Ron,

Your on a slippery slope. Digital displays and already planning your
next electrical upgrade! Could be evidence of that dreaded
psychological disorder known as Airventure Syndrome. We'll keep an
eye out for the major symptoms, obsessive urges to install IFR glass
panels, researching the installation of autopilot systems and weather
radar, and the most serious sympton requiring medication a small

I probably shouldn't confess this, but ever since the Dynon folks gave a
presentation at the EAA Chapter, I've really had the urge to install one
of their EFIS boxes on my Fly Baby. Just for the jaw-dropping
incongruity of it, if nothing else....

Ron Wanttaja

Install the EFIS and double the value of your Flybaby.... grin...

John

Ron Wanttaja wrote:
canuck_bob wrote:
Gee Ron,

Your on a slippery slope. Digital displays and already planning your
next electrical upgrade! Could be evidence of that dreaded
psychological disorder known as Airventure Syndrome. We'll keep an
eye out for the major symptoms, obsessive urges to install IFR glass
panels, researching the installation of autopilot systems and weather
radar, and the most serious sympton requiring medication a small

I probably shouldn't confess this, but ever since the Dynon folks gave a
presentation at the EAA Chapter, I've really had the urge to install one
of their EFIS boxes on my Fly Baby. Just for the jaw-dropping
incongruity of it, if nothing else....

Ron Wanttaja