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Karl Townsend May 17th 12 05:59 PM

need cheap tach
 
I put a http://www.tinytach.com/ on my tractors five years ago. Very
useful. It wore out the battery and i got another. the new one desn't
work because it picks up signals from all spark plugs. I just got off
the phone with their very nice tech. service guy. The old units, model
4C had a filter. The new ones, model 4A, don't. He's finding an old
one to get me going.

OK, that works, this time. But the other tractor will wear out soon
(five year battery life) so i need to get something else. I REALLY
like the digital readout. Anybody suggest a inexpensive tach to
retrofit to an old gasoline engine? I need to know 1350 from 1325 or
1375 RPM.

GWIW, I use these tractors to spray pesticides and fertilizers.
Accurate spped is very important.

karl


P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl

Lloyd E. Sponenburgh[_3_] May 17th 12 06:19 PM

need cheap tach
 
Karl Townsend fired this volley in
:

Anybody suggest a inexpensive tach to
retrofit to an old gasoline engine? I need to know 1350 from 1325 or


Karl,
There are all sorts of small analog tachs available in auto stores for
cheap.

I installed one on my diesel tractor using a hall effect sensor to do the
triggering.

I know it's not digital, but please consider that the digital ones aren't
all _that_ accurate, either.

As far as spraying goes -- are you using a PTO pump? If so, volume will
more-or-less match engine speed, regardless of the _exact_ speed you go.

On a PTO pump, you control volume with flow restriction.


LLoyd


LLoyd

[email protected] May 17th 12 06:19 PM

need cheap tach
 
On May 17, 12:59*pm, Karl Townsend
wrote:

P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


Ask the tech. He can probably tell you exactly what you could add to
a new tach to make it as good as the old tachs.

Dan


[email protected] May 17th 12 06:45 PM

need cheap tach
 
On May 17, 12:59*pm, Karl Townsend
wrote:


GWIW, I use these tractors to spray pesticides and fertilizers.
Accurate spped is very important.

karl

Have you looked at gps receivers? The one with some augmentation as
WAAS might be accurate enough. There is a thread on
sci.electronics,design labeled

Testing the Dealextreme ET411 GPS module


I would think this is a common problem for farmers and Jan might be
interested in developing a system for accurate slow speeds for farmers
needs.

Dan


Lloyd E. Sponenburgh[_3_] May 17th 12 07:12 PM

need cheap tach
 
" fired this volley in news:8c560f45-
:

I would think this is a common problem for farmers and Jan might be
interested in developing a system for accurate slow speeds for farmers
needs.


GPS is useful for maintaining a good pattern, but not really very good
for manually-controlled tractors. The GPS has to drive to make it
accurate.

For the most accurate path control with a manual tractor, one uses a foam
dripper to mark the lines. Dyed foam will be visible for days, unless it
rains hard.

As I said before, the problem of matching application rate to coverage
was long ago solved by using PTO-driven pumps, the volume of which
exactly matches the speed of the tractor (assuming the same gear and not
below the critical "self sealing" pumping speed, of course).

One can calculate gallons-per-acre almost to the quart with a pto pump in
good condition. Within fairly wide variations, speed doesn't matter a
whit.

Of course it takes calibrated nozzles, a known boom width, and all that
other flow-related crap. But once you have the equipment in place, you
make one run over a field with water, figure your consumption, and
develop your concentrations (again, within acceptable ranges) on that.

If the concentration is too low because the volume is too high, you
reduce the number of nozzles or their size. And vice-versa.

This problem was NAILED decades ago.

Lloyd


LLoyd

Spehro Pefhany May 17th 12 07:23 PM

need cheap tach
 
On Thu, 17 May 2012 10:45:54 -0700 (PDT), "
wrote:

On May 17, 12:59*pm, Karl Townsend
wrote:


GWIW, I use these tractors to spray pesticides and fertilizers.
Accurate spped is very important.

karl

Have you looked at gps receivers? The one with some augmentation as
WAAS might be accurate enough. There is a thread on
sci.electronics,design labeled

Testing the Dealextreme ET411 GPS module


I would think this is a common problem for farmers and Jan might be
interested in developing a system for accurate slow speeds for farmers
needs.

Dan


Rockwell has been flogging systems for farmers for years. Dunno how
expensive they are.



Bill[_42_] May 17th 12 07:33 PM

need cheap tach
 
On 5/17/2012 9:59 AM, Karl Townsend wrote:
I put a http://www.tinytach.com/ on my tractors five years ago. Very
useful. It wore out the battery and i got another. the new one desn't
work because it picks up signals from all spark plugs. I just got off
the phone with their very nice tech. service guy. The old units, model
4C had a filter. The new ones, model 4A, don't. He's finding an old
one to get me going.

OK, that works, this time. But the other tractor will wear out soon
(five year battery life) so i need to get something else. I REALLY
like the digital readout. Anybody suggest a inexpensive tach to
retrofit to an old gasoline engine? I need to know 1350 from 1325 or
1375 RPM.

GWIW, I use these tractors to spray pesticides and fertilizers.
Accurate spped is very important.

karl


P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


why not cut the old one open and change the battery? it can't be that
hard - I've changed the battery on some other "permanent' items before
with some success

Jon Elson[_3_] May 17th 12 11:21 PM

need cheap tach
 
Karl Townsend wrote:

I put a http://www.tinytach.com/ on my tractors five years ago. Very
useful. It wore out the battery and i got another. the new one desn't
work because it picks up signals from all spark plugs. I just got off
the phone with their very nice tech. service guy. The old units, model
4C had a filter. The new ones, model 4A, don't. He's finding an old
one to get me going.

OK, that works, this time. But the other tractor will wear out soon
(five year battery life) so i need to get something else. I REALLY
like the digital readout. Anybody suggest a inexpensive tach to
retrofit to an old gasoline engine? I need to know 1350 from 1325 or
1375 RPM.

Can you crack the case open and replace the battery inside?

Jon

Karl Townsend May 18th 12 02:10 AM

need cheap tach
 
On Thu, 17 May 2012 13:12:13 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

" fired this volley in news:8c560f45-
:

I would think this is a common problem for farmers and Jan might be
interested in developing a system for accurate slow speeds for farmers
needs.


GPS is useful for maintaining a good pattern, but not really very good
for manually-controlled tractors. The GPS has to drive to make it
accurate.

For the most accurate path control with a manual tractor, one uses a foam
dripper to mark the lines. Dyed foam will be visible for days, unless it
rains hard.

As I said before, the problem of matching application rate to coverage
was long ago solved by using PTO-driven pumps, the volume of which
exactly matches the speed of the tractor (assuming the same gear and not
below the critical "self sealing" pumping speed, of course).

One can calculate gallons-per-acre almost to the quart with a pto pump in
good condition. Within fairly wide variations, speed doesn't matter a
whit.

Of course it takes calibrated nozzles, a known boom width, and all that
other flow-related crap. But once you have the equipment in place, you
make one run over a field with water, figure your consumption, and
develop your concentrations (again, within acceptable ranges) on that.

If the concentration is too low because the volume is too high, you
reduce the number of nozzles or their size. And vice-versa.

This problem was NAILED decades ago.

Lloyd


LLoyd


I would disagree with you here. I use 3/8 to 1/2 of lable rate on most
every product. That leaves no cushion for error (saves me over $2K a
year) if you're trying to keep application rate variation well under
+/- 5 percent you got to keep everything constant and be very
observant for any sign of wear or plugging. Another huge item is to
exactly finish the tank twenty feet after the last row.

50 RPM will raise the pressure 2 PSI while hardy changing speed. or
you're already 5% higher on field rate. A primary screen plugging
will drop you 1 or 2 psi if you're positive its not RPM, you can spot
it right away. I'm also logging pump and nozzle wear from day to day
and making minor gal/acre adjustments. Again if you keep everything
constant, ths is easy to spot

most folks don't believe me when i tell them farming is more techical
than they know.

karl





Steve B[_13_] May 18th 12 02:27 AM

need cheap tach
 

"Karl Townsend" wrote in message
...
I put a http://www.tinytach.com/ on my tractors five years ago. Very
useful. It wore out the battery and i got another. the new one desn't
work because it picks up signals from all spark plugs. I just got off
the phone with their very nice tech. service guy. The old units, model
4C had a filter. The new ones, model 4A, don't. He's finding an old
one to get me going.

OK, that works, this time. But the other tractor will wear out soon
(five year battery life) so i need to get something else. I REALLY
like the digital readout. Anybody suggest a inexpensive tach to
retrofit to an old gasoline engine? I need to know 1350 from 1325 or
1375 RPM.

GWIW, I use these tractors to spray pesticides and fertilizers.
Accurate spped is very important.

karl


P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


I got a freaking one for my SA200 welder, 1450 rpm, and it's still in the
box. Will come back whenever I hook it up. Northern Tools, IIRC.

HEY, DON'T BUG ME, I'M BUSY!

Steve



Lloyd E. Sponenburgh[_3_] May 18th 12 02:52 AM

need cheap tach
 
Karl Townsend fired this volley in
:

most folks don't believe me when i tell them farming is more techical
than they know.


It certainly is now. With that, I'll agree. With the other, we'll have
to disagree. My opinion, of course, but I think if you get variations as
wide as you say for any reason other than nozzle erosion and pump wear,
something isn't right. Slip in the drive train, worn pump rollers...
something. Is yours a big field machine with an automatic tranny?
Torque converter maybe doesn't lock up completely?

Everybody uses less than the label rate, if they can get uniform
coverage, and if it works at those levels and prevailing weather. If
I'm spraying Basogran, I'd _LIKE_ to use 1/10th label... but it doesn't
work that way. Then there's Sonar for the pond and irrigation ditches...
sigh

Karl, I don't have a "real" farm, just 20 acres in turf grass sod. So
YMMV on "real" crops. My numbers have to come out close, too. Sod sells
for cheap, unless you're the cutter/distributor.

Lloyd

Spehro Pefhany May 18th 12 03:33 AM

need cheap tach
 
On Thu, 17 May 2012 11:59:41 -0500, the renowned Karl Townsend
wrote:




P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


I'm not sure why a filter would be required- looks like you could
reduce the sensitivity using shielded wire and maybe a single turn
around the ignition wire. No?


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Karl Townsend May 18th 12 12:23 PM

need cheap tach
 
On Thu, 17 May 2012 22:33:46 -0400, Spehro Pefhany
wrote:

On Thu, 17 May 2012 11:59:41 -0500, the renowned Karl Townsend
wrote:




P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


I'm not sure why a filter would be required- looks like you could
reduce the sensitivity using shielded wire and maybe a single turn
around the ignition wire. No?


Best regards,
Spehro Pefhany


I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?

Karl


Spehro Pefhany May 18th 12 01:42 PM

need cheap tach
 
On Fri, 18 May 2012 06:23:10 -0500, the renowned Karl Townsend
wrote:

On Thu, 17 May 2012 22:33:46 -0400, Spehro Pefhany
wrote:

On Thu, 17 May 2012 11:59:41 -0500, the renowned Karl Townsend
wrote:




P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


I'm not sure why a filter would be required- looks like you could
reduce the sensitivity using shielded wire and maybe a single turn
around the ignition wire. No?


Best regards,
Spehro Pefhany


I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?

Karl


Is the pickup wire shielded now? Shield grounded?


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Joseph Gwinn May 18th 12 04:04 PM

need cheap tach
 
In article ,
Karl Townsend wrote:

On Thu, 17 May 2012 22:33:46 -0400, Spehro Pefhany
wrote:

On Thu, 17 May 2012 11:59:41 -0500, the renowned Karl Townsend
wrote:




P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl


I'm not sure why a filter would be required- looks like you could
reduce the sensitivity using shielded wire and maybe a single turn
around the ignition wire. No?


Best regards,
Spehro Pefhany


I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?


A classic dodge would be to pass the sparkplug wire through the center
of a ferrite toroid upon which a few hundred turns of fine wire had been
wound, forming a simple current transformer. The fine-wire winding
would be connected to a bit of coax which would carry the signal to the
tach. The winding can be shielded (so long as the shielding does not
form a closed metallic loop).

This will sense the current drawn by the spark, not the spark voltage.

Joe Gwinn

Karl Townsend May 18th 12 04:51 PM

need cheap tach
 
On Fri, 18 May 2012 08:42:28 -0400, Spehro Pefhany
wrote:

On Fri, 18 May 2012 06:23:10 -0500, the renowned Karl Townsend
wrote:

On Thu, 17 May 2012 22:33:46 -0400, Spehro Pefhany
wrote:

On Thu, 17 May 2012 11:59:41 -0500, the renowned Karl Townsend
wrote:




P.S. Extra bonus question, any way to just figure what the old ones
had for a filter?

Karl

I'm not sure why a filter would be required- looks like you could
reduce the sensitivity using shielded wire and maybe a single turn
around the ignition wire. No?


Best regards,
Spehro Pefhany


I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?

Karl


Is the pickup wire shielded now? Shield grounded?

yes and yes, all but the last one inch. The tech. had me cut it down
in an effort to correct the problem.

The guy at Tiny Tach is GREAT. He's making me two custom tachs with
filters. So, I'm good for five more years. I'll worry about it then.
or, with luck, I'll be retired and fishing full time.

Karl



Best regards,
Spehro Pefhany


Karl Townsend May 18th 12 04:55 PM

need cheap tach
 
....
It certainly is now. With that, I'll agree. With the other, we'll have
to disagree. My opinion, of course, but I think if you get variations as

....

WHAT, Agreeing to disagree without yelling and screaming and calling
each other names? I guess we're out of step, its not done this way
anymore :)

Karl


Lloyd E. Sponenburgh[_3_] May 18th 12 05:10 PM

need cheap tach
 
Karl Townsend fired this volley in
:

WHAT, Agreeing to disagree without yelling and screaming and calling
each other names? I guess we're out of step, its not done this way
anymore :)


G
Lloyd

Steve W.[_4_] May 18th 12 10:28 PM

need cheap tach
 
Karl Townsend wrote:
I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?

Karl



Karl, how about a photo tach reading impulses directly off the PTO?
Small spot of reflective tape and mount the sensor and you should be OK.

--
Steve W.

Steve W.[_4_] May 18th 12 10:29 PM

need cheap tach
 
Karl Townsend wrote:
yes and yes, all but the last one inch. The tech. had me cut it down
in an effort to correct the problem.

The guy at Tiny Tach is GREAT. He's making me two custom tachs with
filters. So, I'm good for five more years. I'll worry about it then.
or, with luck, I'll be retired and fishing full time.

Karl


Hope you have better luck than me with the fish. The bite seems REALLY
screwed up this year.

--
Steve W.

David Billington May 18th 12 10:48 PM

need cheap tach
 
Steve W. wrote:
Karl Townsend wrote:
I'm going to play more with this idea. the vendor had me cut the lead
down to one inch and use just a hook, no joy. I think I'll try to
increase the distance by wrapping a gob of elctrical tape around the
plug wire.

I assume you're thinking AL foil. Which wire would you wrap, plug wire
or unit pickup lead, and should it be grounded?

Karl



Karl, how about a photo tach reading impulses directly off the PTO?
Small spot of reflective tape and mount the sensor and you should be OK.

Karl might even be able to use a bike computer for the job when
calibrated. I've read about people that have fitted them to disc/drums
and they worked fine but having the pick-up on the propshaft was too
fast. That was for car use and I would suspect a tractor and the PTO to
be somewhat slower so may be OK.

Karl Townsend May 18th 12 11:13 PM

need cheap tach
 
On Fri, 18 May 2012 17:29:46 -0400, "Steve W."
wrote:

Karl Townsend wrote:
yes and yes, all but the last one inch. The tech. had me cut it down
in an effort to correct the problem.

The guy at Tiny Tach is GREAT. He's making me two custom tachs with
filters. So, I'm good for five more years. I'll worry about it then.
or, with luck, I'll be retired and fishing full time.

Karl


Hope you have better luck than me with the fish. The bite seems REALLY
screwed up this year.


For me, just getting to go is enough luck. I've found its impossible
to worry and fish at the same time. That said, last season was the
best of my short life. Well, maybe the one day salmon trip off the
coast of WA in 1976 was better.

Karl


Steve W.[_4_] May 19th 12 02:29 AM

need cheap tach
 
Karl Townsend wrote:
On Fri, 18 May 2012 17:29:46 -0400, "Steve W."
wrote:

Karl Townsend wrote:
yes and yes, all but the last one inch. The tech. had me cut it down
in an effort to correct the problem.

The guy at Tiny Tach is GREAT. He's making me two custom tachs with
filters. So, I'm good for five more years. I'll worry about it then.
or, with luck, I'll be retired and fishing full time.

Karl

Hope you have better luck than me with the fish. The bite seems REALLY
screwed up this year.


For me, just getting to go is enough luck. I've found its impossible
to worry and fish at the same time. That said, last season was the
best of my short life. Well, maybe the one day salmon trip off the
coast of WA in 1976 was better.

Karl


I've been out in the local streams, a couple larger creeks a lake and
two rivers so far. Other than a few bluegills and a couple suckers I
haven't been getting much. Talking to others they are having similar
luck. Have seen a few hitting spots where they didn't have luck before
and now they are finding fish.

--
Steve W.

[email protected] May 20th 12 09:19 PM

ball mills
 

I tried to email you but failed.

Dan


dlcaster57spamnotyahoo.com

Lloyd E. Sponenburgh[_3_] May 20th 12 10:34 PM

ball mills
 
" fired this volley in news:0379bd7c-
:


I tried to email you but failed.

Dan


dlcaster57spamnotyahoo.com


Didn't fail. It bumped up against my spam-blocker, which notified me.

I will respond.

LLoyd


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