GB -- "VU Meter Amplifier" PCB

[ppcblaster]

I would like to have an affordable pair of the old meter faces

and needle with a dim blue LED. for my BrianGT stereo amp.

[ckwong99]

Hi Jackinnj

Not sure this VU-Meter cct. PCB still available or not ?

If yes , i want to order the full set (PCB+components) ship to HongKong. So what will be the price should be charged.

CK

[jackinnj]

for a meter face you can redimension the face plate using a program like power point, and it is quite easy to slip in a string of blue surface mount leds.

i am sorry that i can't supply a kit of parts -- but everything should be readily available almost anywhere on the planet.

[ppcblaster]

Originally posted by jackinnj
for a meter face you can redimension the face plate using a program like power point, and it is quite easy to slip in a string of blue surface mount leds.

i am sorry that i can't supply a kit of parts -- but everything should be readily available almost anywhere on the planet.

What exactly does this board do? confused.

[jackinnj]

if you go back to the first post or so -- the board implements the attack and decay specified for a VU meter -- (but remember that the original standards were abandoned when modern recording equipment pushed the telco standards out of the way). It has broader dynamic range due to the use of two rail to rail opamps set up as a precision rectifier. The original circuit used a Linear Tech comparator -- but these might be a bit inconvenient for some folks to obtain so I used a garden variety bipolar unit. The circuit appeared in EDN a year ago or so, and I thought I would just make some boards for my own use and knock down the unit cost by doing a GB, offering them out at cost.

[ckwong99]

Hi Jackinnj,

Can you give me advice about the substitution of LT1011 and LT1469 ?

CK

[jackinnj]

In deference to Linear Tech who came up with the idea I showed their parts in the schematic.

I've used another dual comparator -- the LM339 -- the LT1011 is a single, bipolar comparator -- both can sense near ground potential.

I have also used other opamps -- but the LT1469 is very fast, low noise and very acurate (16 bits).

Remember that the point of the device is to change the attack and decay of a VU meter circuit in order to be useful.

[markgall]

Hello,

Are PCB's available for purchase yet or are you still in the prototype stage?

Mark

[ckwong99]

THrough a month of work , just finish a board (single-sided PCB replace with through hole 8-pin OPAMP sockets) use same components like an original introduced. However, my result is out of my thinking that is not work properly. So here seek your comment about this circuit whether anyone can succeed on building that with a good performance result ?

[sklimek]

I finally got this finished but haven't the time yet to test it yet. I pretty much followed the posted schematic and parts.