I have just finished building the K1803.
i have double checked and everything looks to be correctly assembled. this is my first attempt at anything like this but it looks good.
All i seem to be getting out is a low/low-mid oscillation. it does increase in volume when the knob cranked which makes me slightly happy it is being amplified but i can’t fathom out what is causing the noise. no signal sent to it comes through.
any help is massively appreciated
cheers
lloyd
Does it do this when you short the input?
What power supply do you use?
i have a 9v battery
i have removed the original noise, i now have a amplified signal but it is clipping slightly and has some hissy hum noise now.
just for your information, i am plugging a guitar into it.
i understand i might be overloading the input stage.
i am wishing to build a mini amp to boost the output from an audio interface to headphones for a drummer to play to a metronome in a live or studio situation.
what kit would i need for this or can the k1803 be modified?
thanks
The K1803 is a PREamplifier! It is clearly stated that the max. input voltage is 40 mV. You are using a line output! This give several 100’s of mV’s!! Ofcourse you are overloading!
Use an AMPLIFIER kit like the K4001 or the K8066 when you find it (K8066 out of production).
thank you for the reply. im sorry if it bugged you, i am new to electronics and the guy who sold it to me said it would do the job.
will look into the other recommendations
what items give out 40mV or lower then? out of interest
Lower than 40 mV: microphones, record players (phono output), standard pick-up elements of guitars, …