hi all
I have a sound to light unit which is a converted vellaman kit. All i have done is remove the 4 LEDS and added a BD139 and a 2N3055 transistor to drive 2 12V 24W filament bulbs in parallel. Now i had problems initially with the bulbs coming on with no input and then reacting to an input. I was told to change 4 resistors to help overcome this. I want the lights to only come on with an input. I have just managed to test it again with the changes and the proper bulbs and they come on with no input and pulse to an input. without the bulbs plugged in the LED reacts as it should, only coming on to an input. Can someone please help me sort out what i need to do to get the correct reaction with the bulbs on. The circuit runs on a 12V DC battery.
Incidently if the pot is turned to the lowest setting of sensitivity a buzzing is introduced across the voice modulator it is connected to, if i increase the vr setting the noise stops. in the picture it is R28, 31, 32, 33 that where changed. the figures in brackets are the original resistor values. thanks in advance. i am a novice and i am struggling to work out what i need to do to sort it out.
a single 12v 2.2W bulb works fine if that gives any clue as to what needs tweaking
Regards
Dave
I have a sound to light unit which is a converted vellaman kit. All i have done is remove the 4 LEDS and added a BD139 and a 2N3055 transistor to drive 2 12V 24W filament bulbs in parallel. Now i had problems initially with the bulbs coming on with no input and then reacting to an input. I was told to change 4 resistors to help overcome this. I want the lights to only come on with an input. I have just managed to test it again with the changes and the proper bulbs and they come on with no input and pulse to an input. without the bulbs plugged in the LED reacts as it should, only coming on to an input. Can someone please help me sort out what i need to do to get the correct reaction with the bulbs on. The circuit runs on a 12V DC battery.
Incidently if the pot is turned to the lowest setting of sensitivity a buzzing is introduced across the voice modulator it is connected to, if i increase the vr setting the noise stops. in the picture it is R28, 31, 32, 33 that where changed. the figures in brackets are the original resistor values. thanks in advance. i am a novice and i am struggling to work out what i need to do to sort it out.
a single 12v 2.2W bulb works fine if that gives any clue as to what needs tweaking
Regards
Dave
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