S Suraj143 Active Member Nov 25, 2010 #1 Hi I made the below siren.It worked but I'm still not satisfy with the sound. Help me to fine tune this circuit. Note that it has not used the pin 3 of the 1st IC. Attachments 555 Siren.gif 5.1 KB · Views: 307
Hi I made the below siren.It worked but I'm still not satisfy with the sound. Help me to fine tune this circuit. Note that it has not used the pin 3 of the 1st IC.
S Suraj143 Active Member Nov 25, 2010 #4 The thing is this is working speedily i need to slow a little bit. I turn the preset but its effective in the near end.That means if I can turn the preset 180" degrees it will effect only 170" - 180".
The thing is this is working speedily i need to slow a little bit. I turn the preset but its effective in the near end.That means if I can turn the preset 180" degrees it will effect only 170" - 180".
Boncuk New Member Nov 25, 2010 #5 Use 100µF instead of 47µF for the timing capacitor of the left hand timer IC. It will change the frequency from 0.318 to 0.149Hz. Boncuk
Use 100µF instead of 47µF for the timing capacitor of the left hand timer IC. It will change the frequency from 0.318 to 0.149Hz. Boncuk
S Suraj143 Active Member Nov 27, 2010 #6 Hello boncuk i changed the c value to 470uf it worked with the timing that i was expected. The txo issues are when power up the sound is very ugly.i think this is due to the charge level of the 470uf cap.how to get a smooth sound when power up? Still the 1st preset is effective in the near end.so its very hard to tune with a screw driver.
Hello boncuk i changed the c value to 470uf it worked with the timing that i was expected. The txo issues are when power up the sound is very ugly.i think this is due to the charge level of the 470uf cap.how to get a smooth sound when power up? Still the 1st preset is effective in the near end.so its very hard to tune with a screw driver.
Boncuk New Member Nov 28, 2010 #7 Next try 47K instead of 2.2K for the top resistor (VCC -> pin7). 470µF seems to be a very high value. Better experiment with the resistors and limit the timing cap to 100µF. Boncuk
Next try 47K instead of 2.2K for the top resistor (VCC -> pin7). 470µF seems to be a very high value. Better experiment with the resistors and limit the timing cap to 100µF. Boncuk
S Suraj143 Active Member Nov 28, 2010 #8 Hi I have changed the below modifications. Please see is it ok? When I supply it from an unregulated supply the sound is not smooth.but if I give it from a SMPS it works smoothly. But still on first time power up the sound is very ugly.Any method to prevent this? Attachments Siren Mod.PNG 10.4 KB · Views: 248 Last edited: Nov 28, 2010
Hi I have changed the below modifications. Please see is it ok? When I supply it from an unregulated supply the sound is not smooth.but if I give it from a SMPS it works smoothly. But still on first time power up the sound is very ugly.Any method to prevent this?