George,

Thank you. This gives some food for thought. Since my VU meter still does not work properly I have several questions.

1. What voltages did you apply to the anodes of the diodes and what voltages were required to engage all 16 blocks of the display in your simulation?
2. What type of diodes did you use?
Is it possible that Proteus introduces some parameters that I cannot obtain on my protoboard and which make all the difference?

My VU meter still does not work properly and:

1. Resets itself every 2 minutes or so.
2. Push button functions as a complete reset and does not change the appearance of the bars.
3. It takes slightly more that 0.1 Volt to activate one bar and it takes about 1.8 Volt to activate all 16 bars.