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Guest

Sat Feb 01, 2020 9:45 pm   



Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.
Thanks,
Eric

default
Guest

Sat Feb 01, 2020 9:45 pm   



On Sat, 01 Feb 2020 11:51:28 -0800, etpm_at_whidbey.com wrote:

Quote:
Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.
Thanks,
Eric


Seems to me I remember seeing a datasheet for the 555 that shows a
capacitor coupled trigger to the trigger input.

https://www.jameco.com/Jameco/workshop/TechTip/555-timer-tutorial.html
Figure 6 shows a complete 555 monostable multivibrator circuit with
simple edge triggering.

Jasen Betts
Guest

Sat Feb 01, 2020 11:45 pm   



On 2020-02-01, etpm_at_whidbey.com <etpm_at_whidbey.com> wrote:
Quote:
Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.


~Reset goes high, so and trigger is low
out goes high, dicharge turns off and the cap starts charging.

when threshold goes high (or reset goes low) the 555 output turns off

if the discharge pin is not connected it will run a single cycle.

can the input connected to reset sink current?


.-------------------------------------------------------------.
| This is an ascii schematic, if the diagram appears garbled |
| try switching to a fixed-pitch font (courier works well) |
| pasting it into notepad works well on ms-windows. |
| or in google groups "show original" (in "more options") |
`-------------------------------------------------------------'

+12
|
. . . .|. . . .
. VCC(Cool .
. .
in --+-----------------RES(4) OUT(3)----- out
| . 555 .
+--[R1]--+---+----TH(6) DIS(7)--
| | . .
| +----TR(2) CV(5)--
| . .
=== . GND(1) .
C1 | . . . .|. . . .
| |
---+--------------+------

C1 1uF
R1 470K

After the signal is removed it'll take about 1 second to re-arm fully,
This could be sped up by putting a diode parallel to R1

Quote:
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.


Another option would be to have a sensor on the slide that detects when
the tool is backed out and then releases the carriage brake, or do
reverse the lathe to return to the start?


--
Jasen.


Guest

Sun Feb 02, 2020 12:45 am   



On Sat, 1 Feb 2020 22:28:53 -0000 (UTC), Jasen Betts
<jasen_at_xnet.co.nz> wrote:

Quote:
On 2020-02-01, etpm_at_whidbey.com <etpm_at_whidbey.com> wrote:
Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.

~Reset goes high, so and trigger is low
out goes high, dicharge turns off and the cap starts charging.

when threshold goes high (or reset goes low) the 555 output turns off

if the discharge pin is not connected it will run a single cycle.

can the input connected to reset sink current?


.-------------------------------------------------------------.
| This is an ascii schematic, if the diagram appears garbled |
| try switching to a fixed-pitch font (courier works well) |
| pasting it into notepad works well on ms-windows. |
| or in google groups "show original" (in "more options") |
`-------------------------------------------------------------'

+12
|
. . . .|. . . .
. VCC(Cool .
. .
in --+-----------------RES(4) OUT(3)----- out
| . 555 .
+--[R1]--+---+----TH(6) DIS(7)--
| | . .
| +----TR(2) CV(5)--
| . .
=== . GND(1) .
C1 | . . . .|. . . .
| |
---+--------------+------

C1 1uF
R1 470K

After the signal is removed it'll take about 1 second to re-arm fully,
This could be sped up by putting a diode parallel to R1

The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.

Another option would be to have a sensor on the slide that detects when
the tool is backed out and then releases the carriage brake, or do
reverse the lathe to return to the start?

Greetings Jasen,
I didn't consider another proximity sensor but your idea would
work. Which is kinda dumb because I'm already using one and have
several more in a drawer. No matter what the tool gets moved either in
or out at the end of the cut. And that motion could be used to switch
the solenoid air valve. Since I already have air lines going to the
carriage it would be easy enough to add wires. Now I have two options
to choose from, though yours seems at first blush to be the simplest.
I just need to figure out how to mount the proximity switch and I will
need to get one that has NC and NO contacts. I could use a micro
switch but I like the proximity switches better for this application
because they are non-contact.
Thanks,
Eric


Guest

Sun Feb 02, 2020 12:45 am   



On Sat, 01 Feb 2020 15:31:11 -0500, default <default_at_defaulter.net>
wrote:

Quote:
On Sat, 01 Feb 2020 11:51:28 -0800, etpm_at_whidbey.com wrote:

Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.
Thanks,
Eric

Seems to me I remember seeing a datasheet for the 555 that shows a
capacitor coupled trigger to the trigger input.

https://www.jameco.com/Jameco/workshop/TechTip/555-timer-tutorial.html
Figure 6 shows a complete 555 monostable multivibrator circuit with
simple edge triggering.

Thanks for the link. It shows me how to do exactly what I want.
Eric


Guest

Sun Feb 02, 2020 9:45 pm   



On Sun, 02 Feb 2020 20:26:39 +0000, Baron <baron_at_linuxmaniac.net>
wrote:

Quote:
etpm_at_whidbey.com prodded the keyboard with:

Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has
a
leadscrew that drives the carriage along the ways when a split
nut-the half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half
nut in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe
will stop repeatably within .004". But the faster the carriage moves
the more overtravel I get. Plus I don't like having so much drag on
the carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time
I want the carriage lock to be actuated. This longer pulse won't be
a problem will it? My plan is to use the proximity switch to pull
the 555 reset low whenever the switch is off. Then the switch will
detect the carriage, the reset will go high and the trigger pulse
will happen. Will this work? Do I need to just pulse the reset? I
could do this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes
and I want the carriage to stop and then be released so I can then
wind the carriage back and prepare for the next pass. I don't want
to fuss around with pressing reset buttons or anything. The way it
is now threading is seamless and reflexive, the lathe is operated
just like normal except I don't have to pull up on the lever to
disengage the half nut. I want to keep it that way.
Thanks,
Eric

Why not simply thread away from the chuck with the lathe in reverse.
Of course you will have to put the threading tool behind the work.
Otherwise it is no different and there will be no risk of running into
the chuck.

I thread this way all the time. Fascinating to watch threads appearing
at 300 rpm !

There are all sorts of reasons not to thread away from the chuck. For
eaxmple, if you goof when engaging the half nut you have no chance of
disengaging it before the work is ruined. And I thread fast, 600 RPM
or more if I can to keep the surface speed up for a good finish on
small diameter parts. And right now, with the air cylinder disengaging
the half nut it is easy to thread parts fast. I can't believe I never
thought of this before. It works so effing good.
Eric

Baron
Guest

Sun Feb 02, 2020 9:45 pm   



etpm_at_whidbey.com prodded the keyboard with:

Quote:
Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has
a
leadscrew that drives the carriage along the ways when a split
nut-the half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half
nut in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe
will stop repeatably within .004". But the faster the carriage moves
the more overtravel I get. Plus I don't like having so much drag on
the carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time
I want the carriage lock to be actuated. This longer pulse won't be
a problem will it? My plan is to use the proximity switch to pull
the 555 reset low whenever the switch is off. Then the switch will
detect the carriage, the reset will go high and the trigger pulse
will happen. Will this work? Do I need to just pulse the reset? I
could do this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes
and I want the carriage to stop and then be released so I can then
wind the carriage back and prepare for the next pass. I don't want
to fuss around with pressing reset buttons or anything. The way it
is now threading is seamless and reflexive, the lathe is operated
just like normal except I don't have to pull up on the lever to
disengage the half nut. I want to keep it that way.
Thanks,
Eric


Why not simply thread away from the chuck with the lathe in reverse.
Of course you will have to put the threading tool behind the work.
Otherwise it is no different and there will be no risk of running into
the chuck.

I thread this way all the time. Fascinating to watch threads appearing
at 300 rpm !

--
Best Regards:
Baron.

Ralph Mowery
Guest

Sun Feb 02, 2020 10:45 pm   



In article <obce3fltq7mtuenlin719f02vaeg1qnn0v_at_4ax.com>,
etpm_at_whidbey.com says...
Quote:
sorts of reasons not to thread away from the chuck. For
eaxmple, if you goof when engaging the half nut you have no chance of
disengaging it before the work is ruined. And I thread fast, 600 RPM
or more if I can to keep the surface speed up for a good finish on
small diameter parts. And right now, with the air cylinder disengaging
the half nut it is easy to thread parts fast. I can't believe I never
thought of this before. It works so effing good.
Eric



Instead of the 555 circuits you may want to check out the Arduino
processor boards. They are usually less than $ 5 and they have timers
you can set and input pins that only need to go high or low logic. Easy
to reprogram for different times and several inputs and outputs. If you
only had 2 or 3 different settings you could set up a selector switch
for that.

~misfit~
Guest

Sat Mar 07, 2020 8:45 am   



On 2/02/2020 9:31 am, default wrote:
Quote:
On Sat, 01 Feb 2020 11:51:28 -0800, etpm_at_whidbey.com wrote:

Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.
Thanks,
Eric

Seems to me I remember seeing a datasheet for the 555 that shows a
capacitor coupled trigger to the trigger input.

https://www.jameco.com/Jameco/workshop/TechTip/555-timer-tutorial.html
Figure 6 shows a complete 555 monostable multivibrator circuit with
simple edge triggering.


I also thank you for the link, I bookmarked it. I have a couple breadboards and bought some 555s a
while back to play with but have yet to do anything with them.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy little classification
in the DSM"
David Melville

This is not an email and hasn't been checked for viruses by any half-arsed self-promoting software.

default
Guest

Sat Mar 07, 2020 6:45 pm   



On Sat, 7 Mar 2020 20:25:28 +1300, ~misfit~
<shaun.at.pukekohe_at_gmail.com> wrote:

Quote:
On 2/02/2020 9:31 am, default wrote:
On Sat, 01 Feb 2020 11:51:28 -0800, etpm_at_whidbey.com wrote:

Recently I added an air cylinder to a manual lathe that opens the
half nut when threading by moving the proper lever.
For those who don't know a manual lathe that can cut threads has a
leadscrew that drives the carriage along the ways when a split nut-the
half nut-is clamped around the leadscrew.
When the carriage has traveled the desired distance the half nut
must be disengaged. The faster the carriage is moving the less time
you have to disengage the half nut. Failure to disengage the half nut
in time typically results in scrap parts or worse.
As I have gotten older my reflexes have gotten worse so I can't
thread as fast as I use to. So to move the lever I added an air
cylinder that is actuated by a solenoid valve that is switched by an
inductive proximity switch. It works very well.
But there is some drift after the half nut opens. I can set the
carriage lock so that it drags some while threading and the lathe will
stop repeatably within .004". But the faster the carriage moves the
more overtravel I get. Plus I don't like having so much drag on the
carriage.
So now I want to add another air cylinder that locks the carriage
for half a second or so whenever the half nut is opened. A 555
monostable timer seems to me to be the best option.
I have some questions though. Because of the way the proximity
switch works the trigger pulse to the 555 will longer than the time I
want the carriage lock to be actuated. This longer pulse won't be a
problem will it? My plan is to use the proximity switch to pull the
555 reset low whenever the switch is off. Then the switch will detect
the carriage, the reset will go high and the trigger pulse will
happen. Will this work? Do I need to just pulse the reset? I could do
this with another 555, or just use a 556 chip.
The whole reason for actuating the carriage lock for just a half
second or so is that the thread being cut requires several passes and
I want the carriage to stop and then be released so I can then wind
the carriage back and prepare for the next pass. I don't want to fuss
around with pressing reset buttons or anything. The way it is now
threading is seamless and reflexive, the lathe is operated just like
normal except I don't have to pull up on the lever to disengage the
half nut. I want to keep it that way.
Thanks,
Eric

Seems to me I remember seeing a datasheet for the 555 that shows a
capacitor coupled trigger to the trigger input.

https://www.jameco.com/Jameco/workshop/TechTip/555-timer-tutorial.html
Figure 6 shows a complete 555 monostable multivibrator circuit with
simple edge triggering.

I also thank you for the link, I bookmarked it. I have a couple breadboards and bought some 555s a
while back to play with but have yet to do anything with them.


The 555 is a very handy device. If you look at the internal workings
(comparators, flip flop, discharge transistor) and think outside the
box, there's a lot of handy-dandy "off-label" uses it can be applied
to. I've used it for thermostats, voltage regulation, battery
charger, and a fail-safe heater control.

~misfit~
Guest

Wed Mar 11, 2020 2:45 am   



On 8/03/2020 5:59 am, default wrote:
Quote:
On Sat, 7 Mar 2020 20:25:28 +1300, ~misfit~
shaun.at.pukekohe_at_gmail.com> wrote:
On 2/02/2020 9:31 am, default wrote:
snipped
Seems to me I remember seeing a datasheet for the 555 that shows a
capacitor coupled trigger to the trigger input.

https://www.jameco.com/Jameco/workshop/TechTip/555-timer-tutorial.html
Figure 6 shows a complete 555 monostable multivibrator circuit with
simple edge triggering.

I also thank you for the link, I bookmarked it. I have a couple breadboards and bought some 555s a
while back to play with but have yet to do anything with them.

The 555 is a very handy device. If you look at the internal workings
(comparators, flip flop, discharge transistor) and think outside the
box, there's a lot of handy-dandy "off-label" uses it can be applied
to. I've used it for thermostats, voltage regulation, battery
charger, and a fail-safe heater control.


That's part of the reason I bought some and decided that I'd like to play with them a bit. I just
haven't got around to it.

Cheers.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy little classification
in the DSM"
David Melville

This is not an email and hasn't been checked for viruses by any half-arsed self-promoting software.

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