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Warble or sweep AF generator

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Boncuk

New Member
Hi,

I'm working at a project to open gates automatically. When I was about designing an alarm circuit to indicate emergency power cut-off in case the gate is jammed I got the idea that a sweeped tone won't be overheared easily.

I found chips for telephone ringers, but they are single tone only. (The same can be done making a gated oscillator circuit using a CD4093).

Is there any IC out there which is easy to use?

Regards

Boncuk
 

dougy83

Well-Known Member
You can make either of the warble or sweep oscillators using 2 gates of your cd4093. Set 1 gate up for the high frequency (carrier) and 1 gate for the low freq (modulator) oscillator. Connect the inputs of 1 oscillator to the other using a resistor, this will modulate the frequency of the high frequency osc.

The resistor connecting the 2 oscillators should have a higher value than the feedback resistors on each oscillator.
 

Boncuk

New Member
You can make either of the warble or sweep oscillators using 2 gates of your cd4093. Set 1 gate up for the high frequency (carrier) and 1 gate for the low freq (modulator) oscillator. Connect the inputs of 1 oscillator to the other using a resistor, this will modulate the frequency of the high frequency osc.

The resistor connecting the 2 oscillators should have a higher value than the feedback resistors on each oscillator.
Thanks Doug,

I tried that already. Sounds awefully ugly. :D

Boncuk
 

dougy83

Well-Known Member
It's not ugly and it works.

You could instead use 2 555s or a 556 to produce the 2 oscillators. The output of the low freq one is fed through an RC into the control input of the high freq one. This also works and is not ugly.
 
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audioguru

Well-Known Member
Most Helpful Member
Radioshack used to have a horrible-sounding people detector at its entrance/exit. It produce square-waves like electric guitar fuzz and did not sound like a smooth chime. It was DING-DONG!
 

Sceadwian

Banned
The one's around here still do. Grates on my ears something fierce, one more reason NOT to go into a Radio Shack =)
 

Boncuk

New Member
The one's around here still do. Grates on my ears something fierce, one more reason NOT to go into a Radio Shack =)
About the same as with 7-11 shops in Thailand. They all use the same signal when a customer enters or leaves. :)
 

tcmtech

Banned
Most Helpful Member
Radioshack used to have a horrible-sounding people detector at its entrance/exit. It produce square-waves like electric guitar fuzz and did not sound like a smooth chime. It was DING-DONG!
Dang! I can still here that thing just in my thoughts!
Guess that means I am not able to withstand sublimenal mind control after all. :(
 

ccurtis

Well-Known Member
You could also get one of the DTMF generator chips. They produce sine wave output, without the buzz. If you press two keys, you get a single frequency (rather than the usual two frequency mix), from which several different tones can be generated. You can alternate between them for warble. Simple. No chirp, though.
 

Boncuk

New Member
I've tried a lot of the suggested circuits and still they sound ugly.

How about that? It's supposed to simulate warship alert. (starts at low frequency and winds up to max - silence - restart).

Anyone tried that yet?

Boncuk
 

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Sceadwian

Banned
And this is where I come in and say 'use a micro controller' =)
 

Boncuk

New Member
And this is where I come in and say 'use a micro controller' =)
Convinced. :D

With the latest schematic I posted there is a problem. Whenever the trigger output of timer1 is connected to the control voltage pin of timer2, timer1 quits oscillating. :(

Boncuk
 

Boncuk

New Member
Does it really matter if the tone is annoying if it sounds only when the gate is jammed?
It matters a lot to me. :)

Being perfectionist also an alarm tone should have good quality - not like a screaming barn gate.

Boncuk
 

Sceadwian

Banned
I'm with mneary now =\ If you want someone to notice your alarm you gotta make it irritating.
 

tcmtech

Banned
Most Helpful Member
Being perfectionist also an alarm tone should have good quality
Audiophile? Or OCD type? :p:D


Arnt warning alarms by design supposed to be annoying and unpleasant to the ear? :confused:
Its what makes you take notice and correct the problem!

If industrial equipment back up alarms played your favorite song in 7.1 suround sound at the perfect volume would you still jump out of the way so quikely?
 

Boncuk

New Member
Audiophile? Or OCD type? :p:D
Sorry, what's OCD?

Arnt warning alarms by design supposed to be annoying and unpleasant to the ear? :confused:
Its what makes you take notice and correct the problem!
I guess an alarm just has to be an unusual sound.

If industrial equipment back up alarms played your favorite song in 7.1 suround sound at the perfect volume would you still jump out of the way so quikely?
I only know of 5.1 surround sound until now. I also won't jump out of the way. Even battle tanks give me the right of way. :D

Boncuk
 

vortex2009

New Member
Hi, Boncuk,
I've just joined on here "Hi" are those People detectors, still available? if so where can I get one please.?
And did you mange to get your sweep Generator completed?
cheers
vortex2009
 

Sceadwian

Banned
OCD = Obsessive compulsive
 
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