thanks again for replying
actually 6 out of 7 are infra red leds lol sorry again i should of said that.
Lesson learnt i will provide every detail in future.
I'm still confused though, is the output waveform i am seeing at pin 7 of the lm311 what is to be expected?
What does the 2.2nf capacitor parallel the 4.7k resistor do?
Its not my cirucit, its a project from a magazine.
An amplified lowpass filtered audio signal is supplied to the noninverting input of the lm311, then modulated with the 100khz triangle wave and sent via the infra red leds.
The magazine artical mentions they have provided some trebble boost is this what the 2.2nf and 4.7k resistor do?
Im building a wooden enclosure for this transmitter and im at the stage where once its in it wont be coming back out so am trying to make sure everything is working ok.
also i removed all components after pin7 to see if i would get a rectangular wave and ofcourse i did
so is the waveform im getting expected with the components in place or do you think i have misconnected them?