Description : This was based on an LM 3915 IC and also worked well with an LM 3916 IC. These were bought through eBay
Built using 10 - 10mm thick plexiglass sheets purchased precut to size (5" x 6"), 20 - 5mm LED's (9 colors) wired in parallel for the plexiglass sheets and the arrays also wired in parallel and a 6V DC 1A adapter to power the project. Base of the project was just a wooden frame with some plexiglass added for a top and front panel. It measures approx. 8"D x 7"W x 3"H. Total height of the project is about 15".
Here's the basic circuit I used.
www.eleccircuit.com/electronic...
I also added an LM386 Audio Amp before the input of the above circuit. A 10k pot was used for volume control. A 5mm blue LED was wired to the power switch.
An example of this is shown from another LM3915 circuit.
www.pira.cz/enbar.htm
Pin 6 of the Audio Amp was wired to V+ in the above basic circuit and pin 5 was wired to the "input from amp" side in the same circuit.
The plexiglass was purchased from www.tapplastics.com in the US at a cost of about US $40 plus shipping.
Update 7/14/16...The video shows the lowest LEDS in the tower remain dimly lit in dot mode. A fix for this was posted by TheVarooj. Adding a 10k resistor across pin 1 of the IC and V+ will correct this.
17 дек 2014
