Hi. I am trying to build this transmitter circuit as attached, but I don’t know how to find the component values based on the LED i am using. The LED is;
“BROADCOM LIMITED HLMP-EG1A-Z10DD LED, Red, Through Hole, T-1 3/4 (5mm), 20 mA, 2.1 V, 630 nm”
https://s3.amazonaws.com/iedu-attac...3a0b03bc_b58bb247c541155b7d34765f7368dbf4.png

 

And this is a digital design???

You can use any LED that reasonable meets the specs given. So go to DigiKey or Mouser and use their selection/search utilities to find reasonable alternatives. There will be no shortage of them.

 

RE:""I dont know how to calculate them""
Very easy, by means of Ohm`s law
First You do is set the led current. Voltage is Vcc-Vce-Vfd, where last two is 0,5...1 and 0,7...2,2 depending on datasheets. Vcc is Your battery voltage.
Then You divide this current by beta (sth around 100) and multiply with decent oversating factor, say 1,3...3, that will be Your base current.
Then calculate the base divider, thermal stability etc etc. There is one beautiful instrument for this aim, named AppCAD.

 

And this is a digital design???

You can use any LED that reasonable meets the specs given. So go to DigiKey or Mouser and use their selection/search utilities to find reasonable alternatives. There will be no shortage of them.

My apologies. I misread your post. I thought you were having problems finding the LED called for in a schematic.

After looking at the attached schematic, it appears to be coursework of some kind. Is it?

 

It is a normal transmitter circuit i want to build as i want to try abd send some frequency signals.

 

R3 needs to be lowered to 220 ohms,C1 will have an Xc from 8K to 72 ohms in your Frequency range.

Here is a better circuit. ..

 

The values look about right for a peak of 20 ma.