These level meters have 22 LEDs arranged as two rows of eleven and could be set to display in bar or dot mode. These level meters mark the final version of the circuit used. The only change is the specific LEDs used. These displays use either the LM3914, LM3915 or LM3916 depending on the application. I still build and sell these units for use in computers and other projects. They come as shown (except with an updated PCB) or using a Bar Graph LED display. LEDs can be the color / size of your choice. Line-Level or power output can be measured.
The top set represents the multi-color version of these level meters using 3mm LEDs. Five are green, three are yellow and three are red. The first LED in each row shows power to the meters and thus is on whenever the meters have power, regardless of whether or not there is a signal. The bottom set shows a single color version of these level meters with some red rectangular LEDs I happened to have in my parts cabinet. Here are a couple of videos showing these audio level meters in action.
THIS IS A RESTORED ARCHIVE PROJECT AND AS SUCH MAY BE MISSING PHOTOS, PARTS LIST, SCHEMATIC, SOURCE CODE, ETC.