pulsing ouput to solid

[Chris Moylan]

So if I don't need always-on 12VDC, I figure I'll attach GND to the
negative output on the 12V pulsing supply, positive to the 1HZ
input...what shall I do with the "+12V" connection in your design?
Are they both connected to the pulsing output? Or both grounds for
the 12V supply and the neg-side(either) of the relay bonded together,
the other side of the coil to "OUT" and the positive supply source for
the relay to "+12V"? Won't the relay still trigger at all times by
power sneaking through R3 into the positive side of the relay coil?

Chris

oh ok then...

+12v>----+----------------------+-------+
| | |
| | [1000]
| | |R3
| [10k] +----->OUT
/_\ Diode |R2 |
| | C
| +------B 2N4401
| | E Q2
cap | D1 R1 C |
1Hz>-||--+---|>|---+--[100K]---B 2N4401 |
| |+ E Q1 |
/_\ diode [10ľf] | |
| | C1 | |
GND>-----+---------+------------+-------+

 

[Terry Pinnell]

Terry Pinnell <terrypin@dial.pipex.com> wrote:

crm0922@rocketmail.com (Chris Moylan) wrote:

Your assessment is correct. The deactivation time is fine anywhere
from 1-4 seconds. The wrinkle is that the bulb will stay lit after
certain alarms and I don't want my subsidiary device to stay activated
in those instances. Is there any way to make the output discharge
even if the input decides to stay high?

Ah, understood. I'd been assuming that all mains power would be
removed when alarm stopped, and that the 'wrinkle' was merely the
trivial issue of the last +ve signal being short (e.g shorter than
500mS).

OK, then it's just a matter of adding capacitor isolation. I have to
leave for weekend in a few minutes, but at a glance something along
the lines N Thornton suggested looks fine. Maybe a slightly different
configuration would allow using a single PNP transistor instead of two
NPNs.

Picked up this thread again on return. Here's a suggested circuit that
I think will be OK:
http://www.terrypin.dial.pipex.com/Images/PulseAlarmChris.gif

Depending on relay resistance and holding current you'll probably need
to do some experiment to get optimum operation.

But, as you see, I'm still unclear exactly what you're trying to do!
Perhaps if you spelt that out *precisely*, including what you want to
happen when pulsing starts and stops (and what power supply will be
used to make it happen), then any remaining ambiguity could be
resolved.

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[John Fields]

On 2 May 2004 21:28:49 -0700, crm0922@rocketmail.com (Chris Moylan)
wrote:

So if I don't need always-on 12VDC, I figure I'll attach GND to the
negative output on the 12V pulsing supply, positive to the 1HZ
input...what shall I do with the "+12V" connection in your design?
Are they both connected to the pulsing output? Or both grounds for
the 12V supply and the neg-side(either) of the relay bonded together,
the other side of the coil to "OUT" and the positive supply source for
the relay to "+12V"? Won't the relay still trigger at all times by
power sneaking through R3 into the positive side of the relay coil?

---
Use Terry's circuit.

--
John Fields

 

[Fred Bloggs]

Chris Moylan wrote:

First of all, the alarm will probably get triggered like once a year,
so I am not worried about the components prematurely wearing because
of a pulsed AC adapter. I just don't want to deal with live AC for
this project, I want to use alarm wire for the run, etc.

Premature aging may be an understatement- it may outright blow the
adapter, and the adapter may not respond to a 2Hz pulsing AC input.

Why do I care at all about 60Hz envelope detectors?

The ac-adapter is your 60Hz envelope detector whether you realize it or not.

 

[Fred Bloggs]

N. Thornton wrote:

It does the job, I think thats the point here.

Maybe- but it has nothing to do with electronics- it's a junk rig and
total crap.

 

[N. Thornton]

Fred Bloggs <nospam@nospam.com> wrote in message news:<40963B69.5060301@nospam.com>...

N. Thornton wrote:

It does the job, I think thats the point here.

Maybe- .......... it's a junk rig and
total crap.

its a rig suited to a hobbyist, it provides what the hobbyist wants.
Of course its not a commercial design. Yours is good for a different
app, but less so for the amateur hobbeast. Best to consider whats most
suited to the client.


Regards, NT

 

[N. Thornton]

Fred Bloggs <nospam@nospam.com> wrote in message news:<409635C5.8010406@nospam.com>...

Chris Moylan wrote:

First of all, the alarm will probably get triggered like once a year,
so I am not worried about the components prematurely wearing because
of a pulsed AC adapter. I just don't want to deal with live AC for
this project, I want to use alarm wire for the run, etc.

Premature aging may be an understatement- it may outright blow the
adapter, and the adapter may not respond to a 2Hz pulsing AC input.

First we're talking wall wart, with a high R transformer, so theres no
problem with any big surge currents or anything popping. It runs
rarely, for limited times and at 50%ish duty cycle. It will have
longer life than always on, not shorter.

Second of course it will respond to 2Hz modulated 50/60Hz.


Regards, NT

 

[Fred Bloggs]

N. Thornton wrote:

Fred Bloggs <nospam@nospam.com> wrote in message news:<409635C5.8010406@nospam.com>...

Chris Moylan wrote:


First of all, the alarm will probably get triggered like once a year,
so I am not worried about the components prematurely wearing because
of a pulsed AC adapter. I just don't want to deal with live AC for
this project, I want to use alarm wire for the run, etc.

Premature aging may be an understatement- it may outright blow the
adapter, and the adapter may not respond to a 2Hz pulsing AC input.


First we're talking wall wart, with a high R transformer, so theres no
problem with any big surge currents or anything popping.
It runs
rarely, for limited times and at 50%ish duty cycle. It will have
longer life than always on, not shorter.

Second of course it will respond to 2Hz modulated 50/60Hz.

It's bad workmanship all around-and this has nothing to do with electronics.

 

[Chris Moylan]

John Fields <jfields@austininstruments.com> wrote in message news:<gpbc90ptrnm2se9g6981a89slf04dsri61@4ax.com>...

On 2 May 2004 21:28:49 -0700, crm0922@rocketmail.com (Chris Moylan)
wrote:

So if I don't need always-on 12VDC, I figure I'll attach GND to the
negative output on the 12V pulsing supply, positive to the 1HZ
input...what shall I do with the "+12V" connection in your design?
Are they both connected to the pulsing output? Or both grounds for
the 12V supply and the neg-side(either) of the relay bonded together,
the other side of the coil to "OUT" and the positive supply source for
the relay to "+12V"? Won't the relay still trigger at all times by
power sneaking through R3 into the positive side of the relay coil?

---
Use Terry's circuit.

Terry's circuit did not take into account the fact that the alarm
light may stay on after the alarm cycle. I do not want my alternate
alarm to run forever after a cycle so the circuit needs to detect the
pulsing and only supply output power when the pulsing is ocurring.

Chris

 

[Chris Moylan]

I think this looks fine Terry. Sorry, in another post someone said to
use your circuit and I pointed out that it didn't meet the
off-when-not-pulsing requirement. This was before I noticed your
followup post as google had it as a response to the earlier thread and
I passed it by while eagerly looking for additional name-calling by
Fred B.

The switched device may be any number of things. From the design you
linked to it appears that you just put an LED as the device. If I
remove everything connected to the relay contacts from your diagram, I
still get a relay that clicks on during pulsing and turns off some few
seconds after the pulsing stops, right?

Thanks again all for the help. I am learning a lot and having some
fun as well.

Chris


Terry Pinnell <terrypin@dial.pipex.com> wrote in message news:<kl2c90lvqrfobn9pckoiotvnmi7ugapp9u@4ax.com>...

Terry Pinnell <terrypin@dial.pipex.com> wrote:

crm0922@rocketmail.com (Chris Moylan) wrote:

Your assessment is correct. The deactivation time is fine anywhere
from 1-4 seconds. The wrinkle is that the bulb will stay lit after
certain alarms and I don't want my subsidiary device to stay activated
in those instances. Is there any way to make the output discharge
even if the input decides to stay high?

Ah, understood. I'd been assuming that all mains power would be
removed when alarm stopped, and that the 'wrinkle' was merely the
trivial issue of the last +ve signal being short (e.g shorter than
500mS).

OK, then it's just a matter of adding capacitor isolation. I have to
leave for weekend in a few minutes, but at a glance something along
the lines N Thornton suggested looks fine. Maybe a slightly different
configuration would allow using a single PNP transistor instead of two
NPNs.

Picked up this thread again on return. Here's a suggested circuit that
I think will be OK:
http://www.terrypin.dial.pipex.com/Images/PulseAlarmChris.gif

Depending on relay resistance and holding current you'll probably need
to do some experiment to get optimum operation.

But, as you see, I'm still unclear exactly what you're trying to do!
Perhaps if you spelt that out *precisely*, including what you want to
happen when pulsing starts and stops (and what power supply will be
used to make it happen), then any remaining ambiguity could be
resolved.

 

[Chris Moylan]

Another dumb question: Are all the diodes the same, or is D3
different than the others? I suppose I should know that if it is
unmarked then it is some standard device you can buy at the
supermarket...my only real electronics experience was some logic
design in college and building a few kits...

The rest of the components look pretty common...

Thanks again,

Chris

Terry Pinnell <terrypin@dial.pipex.com> wrote in message news:<kl2c90lvqrfobn9pckoiotvnmi7ugapp9u@4ax.com>...

Terry Pinnell <terrypin@dial.pipex.com> wrote:

crm0922@rocketmail.com (Chris Moylan) wrote:

Your assessment is correct. The deactivation time is fine anywhere
from 1-4 seconds. The wrinkle is that the bulb will stay lit after
certain alarms and I don't want my subsidiary device to stay activated
in those instances. Is there any way to make the output discharge
even if the input decides to stay high?

Ah, understood. I'd been assuming that all mains power would be
removed when alarm stopped, and that the 'wrinkle' was merely the
trivial issue of the last +ve signal being short (e.g shorter than
500mS).

OK, then it's just a matter of adding capacitor isolation. I have to
leave for weekend in a few minutes, but at a glance something along
the lines N Thornton suggested looks fine. Maybe a slightly different
configuration would allow using a single PNP transistor instead of two
NPNs.

Picked up this thread again on return. Here's a suggested circuit that
I think will be OK:
http://www.terrypin.dial.pipex.com/Images/PulseAlarmChris.gif

Depending on relay resistance and holding current you'll probably need
to do some experiment to get optimum operation.

But, as you see, I'm still unclear exactly what you're trying to do!
Perhaps if you spelt that out *precisely*, including what you want to
happen when pulsing starts and stops (and what power supply will be
used to make it happen), then any remaining ambiguity could be
resolved.

 

[Terry Pinnell]

crm0922@rocketmail.com (Chris Moylan) wrote:

The switched device may be any number of things. From the design you
linked to it appears that you just put an LED as the device. If I
remove everything connected to the relay contacts from your diagram, I
still get a relay that clicks on during pulsing and turns off some few
seconds after the pulsing stops, right?

Correct.

You still haven't said what power supply will activate the 'switched
device'?

If the pulsed mains (and the pulsed 12V DC derived from it) are the
only two power sources available to you (which was the basis for my
design), then it will be activated for a very short period, unless the
pulse hapens to finish in a high state.

On the other hand, if you have some auxiliary mains or DC supply, then
the smoothed supply section of my suggested circuit is surely
redundant?

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[Terry Pinnell]

crm0922@rocketmail.com (Chris Moylan) wrote:

Another dumb question: Are all the diodes the same, or is D3
different than the others? I suppose I should know that if it is
unmarked then it is some standard device you can buy at the
supermarket...my only real electronics experience was some logic
design in college and building a few kits...

It would be hard to find a type that wouldn't work. Any small signal
or rectifier diode in all three locations, such as 1N4148, 1N914,
1N4001, 1N4002 etc.

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[Terry Pinnell]

crm0922@rocketmail.com (Chris Moylan) wrote:

John Fields <jfields@austininstruments.com> wrote in message news:<gpbc90ptrnm2se9g6981a89slf04dsri61@4ax.com>...
On 2 May 2004 21:28:49 -0700, crm0922@rocketmail.com (Chris Moylan)
wrote:

So if I don't need always-on 12VDC, I figure I'll attach GND to the
negative output on the 12V pulsing supply, positive to the 1HZ
input...what shall I do with the "+12V" connection in your design?
Are they both connected to the pulsing output? Or both grounds for
the 12V supply and the neg-side(either) of the relay bonded together,
the other side of the coil to "OUT" and the positive supply source for
the relay to "+12V"? Won't the relay still trigger at all times by
power sneaking through R3 into the positive side of the relay coil?

---
Use Terry's circuit.

Terry's circuit did not take into account the fact that the alarm
light may stay on after the alarm cycle. I do not want my alternate
alarm to run forever after a cycle so the circuit needs to detect the
pulsing and only supply output power when the pulsing is ocurring.

Chris

As you've now seen, you'd missed the later circuit:
http://www.terrypin.dial.pipex.com/Images/PulseAlarmChris.gif

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[N. Thornton]

Fred Bloggs <nospam@nospam.com> wrote in message news:<4096F83F.30206@nospam.com>...

and this has nothing to do with electronics.

that bit I'll agree with you on.

Regards, NT

 

[Chris Moylan]

I think it is safe to assume that whatever device that is being
switched will have its own power supply. So I guess I have missed the
reason why it matters if said device is only connected via the
contacts-side of the relay.

How huge of a cap is the 4700uF guy? Is the voltage rating for the
caps going to make a difference, or is a 16-25V radial electrolytic
fine?

Chris

Terry Pinnell <terrypin@dial.pipex.com> wrote in message news:<b2ke909aqu9f33g7sn7tc6kbnh92jm1tiv@4ax.com>...

You still haven't said what power supply will activate the 'switched
device'?

If the pulsed mains (and the pulsed 12V DC derived from it) are the
only two power sources available to you (which was the basis for my
design), then it will be activated for a very short period, unless the
pulse hapens to finish in a high state.

On the other hand, if you have some auxiliary mains or DC supply, then
the smoothed supply section of my suggested circuit is surely
redundant?

 

[Terry Pinnell]

crm0922@rocketmail.com (Chris Moylan) wrote:

I think it is safe to assume that whatever device that is being
switched will have its own power supply. So I guess I have missed the
reason why it matters if said device is only connected via the
contacts-side of the relay.

You sure are hard to pin down! Once again - what *is* the switched
device? Is it a secret or something? What do you want to happen to it
(and for how long) when
(a) the pulsing starts (about once a year, I understand?)
(b) the pulsing finishes?

How huge of a cap is the 4700uF guy?

Physically quite small. I take it you haven't looked at a paper or
online catalogue yet then?

Is the voltage rating for the
caps going to make a difference, or is a 16-25V radial electrolytic
fine?

That's fine.

--
Terry Pinnell
Hobbyist, West Sussex, UK

Chris

Terry Pinnell <terrypin@dial.pipex.com> wrote in message news:<b2ke909aqu9f33g7sn7tc6kbnh92jm1tiv@4ax.com>...


You still haven't said what power supply will activate the 'switched
device'?

If the pulsed mains (and the pulsed 12V DC derived from it) are the
only two power sources available to you (which was the basis for my
design), then it will be activated for a very short period, unless the
pulse hapens to finish in a high state.

On the other hand, if you have some auxiliary mains or DC supply, then
the smoothed supply section of my suggested circuit is surely
redundant?

 

[Rich Grise]

"Terry Pinnell" <terrypin@dial.pipex.com> wrote in message
news:jvqf90dcep8fh8el69cseq2sdamqon04k0@4ax.com...

crm0922@rocketmail.com (Chris Moylan) wrote:

You sure are hard to pin down! Once again - what *is* the switched
device? Is it a secret or something? What do you want to happen to it
(and for how long) when
(a) the pulsing starts (about once a year, I understand?)
(b) the pulsing finishes?

He's (or she? 'Chris'?) got mains, that are sitting either on or off,
powering a wall wart.

When the state of the 12V from the wall wart changes, turn the
output on, and start your timing cycle.

If the state of the 12V from the wall wart changes again (either
way!) before the time-out, restart the time-out cycle, else
let it run out, regardless of whether the 12V is present or not.

So Chris really wants an either-edge trigger retriggerable one-
shot, and it does look like Chris can't use the switched 12V as
a power supply for the time-out circuit.

Hope this helps!
Rich

 

[Chris Moylan]

You sure are hard to pin down! Once again - what *is* the switched
device? Is it a secret or something? What do you want to happen to it
(and for how long) when
(a) the pulsing starts (about once a year, I understand?)
(b) the pulsing finishes?

I am not being evasive, but there really could be several possible
devices. Candidates are a strobing 12V lamp, a 24V pulsing siren,
120V indicator of some sort in a remote location, etc. I need to
build a couple of these "converters" for a couple outputs (all the
same 120V pulsing jobs) what amounts to a relay that clicks on when
the cycling starts and off after the cycling ends, as we have
discussed.

Perhaps you missed some of my other posts where I described this in
greater detail. Either way, the source device is a monitoring unit
for several sensors in a proprietary alarm system. The outputs are
several 120V lamps that will alarm when certain sensors are tripped.
The lamp will pulse at about 1Hz until either someone stops the alarm
(the light shuts off) or it times out after 5 minutes of flashing
(light stays ON, though!)

At least one of my external devices could be a loud siren in a big
room to draw attention to the alarm state. However, if no one who
knows how to reset the alarm is available, I would like the siren to
shut off even though the lamp on the alarm itself remains on to
indicate the trouble area.

How huge of a cap is the 4700uF guy?

Physically quite small. I take it you haven't looked at a paper or
online catalogue yet then?

I didn't look at a cut sheet for one yet. I was just curious about
how I would package this whole gizmo and whether it would be one of
those huge (2 inch long) things that needs to be bolted to a chassis
or something.

Is the voltage rating for the
caps going to make a difference, or is a 16-25V radial electrolytic
fine?

That's fine.

Thanks once again,

Chris

 

[Chris Moylan]

He's (or she? 'Chris'?) got mains, that are sitting either on or off,
powering a wall wart.

When the state of the 12V from the wall wart changes, turn the
output on, and start your timing cycle.

If the state of the 12V from the wall wart changes again (either
way!) before the time-out, restart the time-out cycle, else
let it run out, regardless of whether the 12V is present or not.

So Chris really wants an either-edge trigger retriggerable one-
shot, and it does look like Chris can't use the switched 12V as
a power supply for the time-out circuit.

Hope this helps!
Rich

I am a he.

This is precisely my situation. Thanks,

Chris