5 t0 12 volts problem

[J4e8a16n]

Hi,

I did another circuit where the the output voltage was coming out of a 555 timer #3 pin to a transistor with a relay (12 volts) working on  12 volts. It was fine.

On this one how could I maintain the base voltage to 1 volt or so? When I clap with the pin 6  to the 5 volts ground. I get 3.75 volts and 30 mA.

The relay is a 12 volts.

[Paul Price]

The base voltage cannot be set higher than approx .7V with your circuit> The ON base-emitter voltage of a silicon BJT sets this limit,

But why try? With your circuit as shown it would work fine with just the resistor in series with the base.

[J4e8a16n]

The base voltage cannot be set higher than approx .7V with your circuit> The ON base-emitter voltage of a silicon BJT sets this limit,

But why try? With your circuit as shown it would work fine with just the resistor in series with the base.

I assume you take note that the bjt is at 12volts and the TTL at 5 volts...

Well why does not this work ...?

Thank you for your interest.

JP

[J4e8a16n]

It does  work 

This app  square the input from the electret then add multiple waves in one long wave . It authaurize only one 'clap'.


I am using an old electret (probably 45dB) with this application and it is not very efficient.

It gives 3 volts at pin 7 .

I have seen a $5 dollars electret  producing 60 decibels.  My problem is I have to clap at least at 2 feet for the application to work.

Have any opinion on this?