Thanks buddy.. I'll build that one and let you know the results.
What does mean 2k2 for the resistors values shown in the diagram?

Oops.. you mean 2.2k... lol

 

Thanks buddy.. I'll build that one and let you know the results.
What does mean 2k2 for the resistors values shown in the diagram?

2k2 is a old way of expressing decimal points developed back when schematics were hand drawn and the copying process (not to mention normal handling) would introduce spots and smudges that could be mistaken for a decimal point. You simply used the scaling prefix as the decimal point. If there wasn't one, like 5.6 Ω, it would be common to use the letter R (in the case of a resistor), making it 5R6.

 

can you duplicate my circuit with my set values (R2= 1M, R1= 1K and C1= 0.01 micro) to compare with my modest oscilloscope readings?
Thank you

My readings.

 

Thanks buddy.. I'll build that one and let you know the results.
What does mean 2k2 for the resistors values shown in the diagram?

.
2K2 is the same as 2.2K .
The Multiplier-Symbol simply replaces the Decimal-Point.
When there is no Multiplier, it is replaced by an "R", such as 470R, or, 3R3 ( 3.3-Ohms ) .
The 3 Resistors may be 1/4 or 1/8th Watt rated.
2K2 is a very common standard size.

The "CMOS" version of the 555, ( 7555 ),
has fewer quirks than the old standby BJT version.
DigiKey has all the parts shown in the Schematic in stock.

If You want higher resolution control of the Frequency,
You can add in a second fine adjustment Pot.
It should be around ~10K, but the value is not critical.

The Duty-Cycle will always be exactly 50%, regardless of Frequency.

The Circuit's Output-Voltage will be within the range of
Supply-Voltage~minus~ 0V to 200mV of the Supply-Voltage with
up to 1-Amp of Output-Current, with very sharp, square edges.
It will comfortably Source, or Sink, 1-Amp of Current.

The Circuit-Breaker-Chip protects the FET-Driver from accidental Short-Circuits to Ground.
It will automatically reset its self after an overload event.
.
.
.

 

The Circuit's Output-Voltage will be within the range of
Supply-Voltage~minus~ 0V to 200mV of the Supply-Voltage with
up to 1-Amp of Output-Current, with very sharp, square edges.

Are you sure about that?
The specs show a high state output resistance of 1.5 ohms at 15 volts supply. That's a loss of 1.5 volts at 1 amp.

 

The mic input might cut high and low frequencies like an old telephone.

 

Are you sure about that?
The specs show a high state output resistance of 1.5 ohms at 15 volts supply. That's a loss of 1.5 volts at 1 amp.

.
You're right .....
I'm used to thinking with a IXDN630MCI which is only 0.17-Ohms,
( but they cost ~$10.oo bucks each piece),
but in any case, he's only asking for ~200mA max,
which comes out to 0.17-Volts, so it will work just fine.
Thanks for finding my mistake, but it's not worth correcting.
.
.
.

 

My readings.

Thanks a lot bro.. now I have more reference to properly calibrate my soft-scope

 

.
You're right .....
I'm used to thinking with a IXDN630MCI which is only 0.17-Ohms,
( but they cost ~$10.oo bucks each piece),
but in any case, he's only asking for ~200mA max,
which comes out to 0.17-Volts, so it will work just fine.
Thanks for finding my mistake, but it's not worth correcting.
.
.
.

Many Thanks for all your replies guys.. it helped a lot.

 

Hello everybody and thank you for all your valuable inputs.
Please note that today I took the circuit (as is) for a test run at the lab and it worked great and gave amazing results with no problems whatsoever.
I'll fine tune the final design and post it later.

Thank you all again.