Very simple to make it but almost impossible to find the circuit diagram

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I want to thank all of you for your kind assistance. I have got the pcb schematics and layout diagram now. He sent it immediately without any fee or cost. This is what being a human and this is what the meaning of our existence.

I am very fortunate to know you.

Now I gotto go now. I have a project to finalize :)
Sir, i already contacted the original author for the schematics but sad to say he did not yet replied on my emails even on facebook and messenger,

sir if you dont mind i would like to ask it from you. please sir.. just send to my email add. <SNIP>

Moderators note : removed email address to avoid spam
 
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Audioguru

Joined Dec 20, 2007
11,251
Why make an old siren circuit that has 100 parts? The datasheet of the LM358 shows a voltage controlled oscillator and the datasheet of the 555 shows that as an oscillator its capacitor voltage sweeps up and down. Connect them together and you have a siren.
The datasheet of the TDA2009A shows a bridged amplifier that with a 12V supply produces a 6W tone or a 12W buzz into an 8 ohm speaker.
Simple.

There is another simple siren circuit on You Tube that uses a Chinese siren IC. The circuit or IC might be sold on ebay, AliExpress or Banggood.
 

MisterBill2

Joined Jan 23, 2018
4,046
The reason to use one of those old circuits is for the specific sound. Yes, you can produce some kind of sound that is sort of similar with a different circuit, but if it is not even close to what you want, why bother?The siren circuits that mount inside the back cover of the horn speaker are a multivibrator made of two power transistors, and they are usually fairly loud. The other extreme is one like the "Federal Interceptor" electronic siren that will deliver 75 watts to the speaker for an hour or more. But it also has a whole lot of other functions on that large circuit board, and two T0-3power transistors on a big heat sink.
 

atferrari

Joined Jan 6, 2004
3,487
Thank you for your suggestion Dick. I put 1N4148 and the circuit works excellent. As far as I have noticed that you are good at this job. If I ask for another suggestion, will it be too much :)

LM 386 gets hot at long period of usage. Output has been supplied over a 220 uF cond. I guess output power is about 1 w. I have used a 8 ohm 5 w eliptic loudspeaker but actually I will use a standard cone siren speaker.

Now I have TDA 2002, TDA 2003, TDA 2009 ( Maybe I can use it in bridge mode ) TDA 2030, 2N3055, 2N2955, IRF 5210, IRF 540 and BD series.

I prefer a specially designed amplifier for this purpose because I will not use it for music or Hi-Fi.

I will be waiting for your suggestion master :)
Is the LM386 oscillating?
 

Audioguru

Joined Dec 20, 2007
11,251
The datasheet for the LM386 shows that it works well with a 6V to 9V supply where it can produce a tone at 0.45W or a buzz at 0.9W into an 8 ohm speaker. Its heating is only 0.5W.

With a 12V supply it can produce a tone at 0.53W or buzz at 1.06W and heats with 0.8W.

The heating is less if the signal is a buzz (squarewave) instead of a tone (sinewave).

A horn speaker produces a horny sound that is difficult to make on an ordinary speaker. The waveform is almost always a severely distorted squarewave buzz with the added horny sound.
 

MisterBill2

Joined Jan 23, 2018
4,046
Once again, I see no circuit drawing that shows a rotary switch, except for that Federal Signal siren, which includes a 100watt amplifier. So the big question here is what does the rotary switch do?. and where is the circuit drawing of what we see in that nice photo of the circuit board assembly?? We have very few good mind readers in this group, and I am not one of them.
 

Audioguru

Joined Dec 20, 2007
11,251
The rotary switch is shown in the video in the first post of this thread. The switch simply changes the sweep rate of the siren from slow to fast.
Without seeing a schematic then somebody needs to guess where to connect the switch.
 

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BobaMosfet

Joined Jul 1, 2009
835
First off all thank you for your effort as writing me.
Nope. I did not try to contact but many people tried and he gave a link on Facebook which is does not exist or it is closed to some people.
He wrote below the video " Sirene polisi dibuat dengan 4 buah transitor, dan untuk audio menggunakan ic LM386 Harga kit Rp. 55.000,- " I guess this is Indian language. I searched for 4 transistors and a LM386 siren circuits on the internet but there is no circuit even a similar one :)
There is a handy little feature in Google that you may not know of- it can translate languages. It can detect languages, too.

translate.google.com

The sentence you posted is Indonesian and says: "Police sirens are made with 4 transistors, and for audio using IC LM386 kit price of Rp. 55,000"

Rp might be 'rupee'.
 

Audioguru

Joined Dec 20, 2007
11,251
I gave up looking on Google for a police siren circuit that uses 4 transistors because the hundreds of circuits shown do not play the sound. Most simply make a doo-dee-doo-dee low pitch, high pitch, low pitch, high pitch beep not a frequency sliding up and down.
 

MisterBill2

Joined Jan 23, 2018
4,046
Hi Gentlemen, may i ask where to put the rotary switch wires onto the board? do you have the wiring schematic?
The connection points are shown clearly on the circuit board in post #26. The terminals are 1A, C, 2A, and 3A. But I have not seen even one circuit drawing for any siren circuit. But using that board layout, with all of the components labeled, you can produce the circuit drawing, and then observe the color codes in the phtos to gain the values of the resistors. After you get that far we can help with the rest.
 

Thread Starter

ilker06

Joined Jun 26, 2018
28
Hi Gentlemen, may i ask where to put the rotary switch wires onto the board? do you have the wiring schematic?
Hi, sorry for my late reply cos I was so busy to join the forum nowadays. As you can see the board made by me, there are switch holes on it. 1 C 2 3 and 1B C 2 3B. I don' t prefer and need the other options I just simply short the ( 1 C ) and ( 1B C ) with a bridge. So you don' t see the rotary switch in my board. Thus I use it in my car like a horn. It sounds when I only push the button.
But if you prefer to use the other options remember that both group contacts should be shorted at the same time with a rotary switch. For example ( 1&C ) and ( 1B&C ) or ( 2&3 ) and ( 2&3B ) etc. Hope it is clear.
The sound tone and the wave quality is excellent. I feel as if I am a real federal cop as I drive my car. The only problem is still the sound level. I use a 16 ohm 100 watt horn unit driver but the amplifier is not suitable to drive it.

Hope someone can help me to solve this problem because I can not find an amplifier schematic to drive a 16 ohm 100 w horn driver unit an may work at 13,5 volt asymmetric power supply :(
 

Audioguru

Joined Dec 20, 2007
11,251
The only problem is still the sound level. I use a 16 ohm 100 watt horn unit driver but the amplifier is not suitable to drive it.

Hope someone can help me to solve this problem because I can not find an amplifier schematic to drive a 16 ohm 100 w horn driver unit an may work at 13,5 volt asymmetric power supply :(
ANY bridged car amplifier can drive a 16 ohm speaker, but with a 13.5V supply the power will be only about 4.1W sinewave or 8W squarewave.
A car amplifier powered from 13.5V is designed to drive a 4 ohm speaker producing about 18W sinewave or 36W squarewave. Some car amplifiers drive 2 ohm speakers with 32W sinewave or 64W squarewave (TDA7396 IC).
High power car amplifiers use an inverter to boost the 13.5V and an amplifier designed for high power powered from the boosted voltage.
 

Thread Starter

ilker06

Joined Jun 26, 2018
28
How "loud" do you want your siren to be, and why?
Hi Mr. Cappels,
I just want to have a similar sound level like police cars. Or close one. They use approximately 15 x 15 x 6 cm boxes to produce this sound level. I mean very compact designs but the sound level are significantly high. Even you can clearly hear it 2 - 3 km away. I have searched for many amplifier circuits on the internet and made most of them but with 13 v it was unsuccessful to catch the same level. I guess there is a different technology in these commercial siren products. I really wonder what kind of amplifier produce this level by 13 v in the car.
And I think I made a mistake buying a 16 ohm horn driver unit but experience is not a value which can be bought :)
Above Audioguru informs about a system using a voltage inverter but I have never seen such circuit schematics in the net by now.
 

Audioguru

Joined Dec 20, 2007
11,251
ALL high power car audio amplifiers use a DC to AC to DC inverter to boost the amplifier's supply voltage.
Simply calculate the power in your 16 ohm horn:
1) A single ordinary amplifier (not used in a car) powered from 13.5V has an output swing of about 10.5V peak-to-peak which is 10.5V/2.828= 3.7V RMS. Then the power into 16 ohms is (3.7V squared)/16 ohms= 0.86W. Into 8 ohms the power is 1.7W and into 4 ohms it is a little less than 3.4W. PUNY power.

2) A car amplifier uses bridged amplifiers that almost double the output voltage swing resulting in about 3.5 times more power.

3) Use an inverter to boost the 13.5VDC to 100VDC and an expensive bridged amplifier can be a less expensive single amplifier. The amplifier output swing will be about 92V p-p which is 92V/2.828= 32.5V RMS and the power into 16 ohms is (32.5V squared)/16 ohms= 66W. Into 8 ohms the power is 132W and into 4 ohms the power is a little less than 264W. LOTS of power.

EDIT: Elliot Sound Products shows many excellent audio amplifiers including one with an output of 1500W! A inverter is shown for a car that produces +35V/-35V at 300W.

Isn't it illegal to "disturb the peace" like the idiots with cars that have the muffler removed?
 

Thread Starter

ilker06

Joined Jun 26, 2018
28
ALL high power car audio amplifiers use a DC to AC to DC inverter to boost the amplifier's supply voltage.
Simply calculate the power in your 16 ohm horn:
1) A single ordinary amplifier (not used in a car) powered from 13.5V has an output swing of about 10.5V peak-to-peak which is 10.5V/2.828= 3.7V RMS. Then the power into 16 ohms is (3.7V squared)/16 ohms= 0.86W. Into 8 ohms the power is 1.7W and into 4 ohms it is a little less than 3.4W. PUNY power.

2) A car amplifier uses bridged amplifiers that almost double the output voltage swing resulting in about 3.5 times more power.

3) Use an inverter to boost the 13.5VDC to 100VDC and an expensive bridged amplifier can be a less expensive single amplifier. The amplifier output swing will be about 92V p-p which is 92V/2.828= 32.5V RMS and the power into 16 ohms is (32.5V squared)/16 ohms= 66W. Into 8 ohms the power is 132W and into 4 ohms the power is a little less than 264W. LOTS of power.

EDIT: Elliot Sound Products shows many excellent audio amplifiers including one with an output of 1500W! A inverter is shown for a car that produces +35V/-35V at 300W.

Isn't it illegal to "disturb the peace" like the idiots with cars that have the muffler removed?
Thank you for the calculation buddy. By the way you are right and I agree with you about the muffler-less cars :) but this siren is not for fun, here in Turkey there are many rule brokers in the street and the only language they understand is this kind of warnings behind them.
 
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