I will TRY to provide enough info here for somebody to maybe be able to help me!
Posit: I have some cool retro analog meters, of various movement types. I want to mount them individually into old refinished wooden radio cabinets, along with some retro rotary switches and Bakelite knobs and jewel lamps... such that the finished unit is looks like some retro-tech device of uncertain origin and purpose. Ergo: “Steampunk”. I have a LOT of these meters, and boxes, and a proximate number of old wall warts, whose outputs range from 6 to 12 VDC, generally 200 – 500mA.
I want to assemble and sell these units at something-approaching a profit. Based on what I'm projecting, my electronic component costs (not including the meters and boxes, time, or labor) need to be on the order of $20 or so.
My dilemma is this: within the above constraints, I want the meter to move. Sure, I could wire a pot and shunt, or I could wire a rotary with differing resistors so the meter reading would change when a control is moved… but I want the meter to appear to move ON ITS OWN volition, as if it were tracking “something”. And I’d like that movement to be either random, or pseudorandom, swinging the meter needle gently to different values, with a period of something upwards of 3 minutes or so.
Assume that a variance of 0 – 3VDC (and probably a lot less!) would do the trick to swing the meters. I’d buffer each meter according to its specific movement.
So. I can do this with Arduino, but the sum per-unit cost of the components exceeds what I can afford, if I hope to break-even, margin-wise. I can do it with combinations of 555’s, etc, but the results are just too rapid and too predictable, and don’t vary. It looks like a saw wave. I can use a standard VU meter breakout board, but again, it’s too pricey, and an onboard mic isn’t sensitive enough, and the end result isn’t the smooth meter swing I’m after.
I have pored over every circuit handbook I could find for the past 6 months, new and ancient, but I cannot find anything that will help me achieve this (admittedly goofy and non-scientific) end, with the minimum possible “currently available” (Jameco et. al.) discrete analog or IC components, in such a way that I can easily build a lot of them.
So… I need IDEAS, and/or a firm kick in the rump, to either get me in the right direction, or to shock me into the reality that “it ain’t possible, bro!”.
Posit: I have some cool retro analog meters, of various movement types. I want to mount them individually into old refinished wooden radio cabinets, along with some retro rotary switches and Bakelite knobs and jewel lamps... such that the finished unit is looks like some retro-tech device of uncertain origin and purpose. Ergo: “Steampunk”. I have a LOT of these meters, and boxes, and a proximate number of old wall warts, whose outputs range from 6 to 12 VDC, generally 200 – 500mA.
I want to assemble and sell these units at something-approaching a profit. Based on what I'm projecting, my electronic component costs (not including the meters and boxes, time, or labor) need to be on the order of $20 or so.
My dilemma is this: within the above constraints, I want the meter to move. Sure, I could wire a pot and shunt, or I could wire a rotary with differing resistors so the meter reading would change when a control is moved… but I want the meter to appear to move ON ITS OWN volition, as if it were tracking “something”. And I’d like that movement to be either random, or pseudorandom, swinging the meter needle gently to different values, with a period of something upwards of 3 minutes or so.
Assume that a variance of 0 – 3VDC (and probably a lot less!) would do the trick to swing the meters. I’d buffer each meter according to its specific movement.
So. I can do this with Arduino, but the sum per-unit cost of the components exceeds what I can afford, if I hope to break-even, margin-wise. I can do it with combinations of 555’s, etc, but the results are just too rapid and too predictable, and don’t vary. It looks like a saw wave. I can use a standard VU meter breakout board, but again, it’s too pricey, and an onboard mic isn’t sensitive enough, and the end result isn’t the smooth meter swing I’m after.
I have pored over every circuit handbook I could find for the past 6 months, new and ancient, but I cannot find anything that will help me achieve this (admittedly goofy and non-scientific) end, with the minimum possible “currently available” (Jameco et. al.) discrete analog or IC components, in such a way that I can easily build a lot of them.
So… I need IDEAS, and/or a firm kick in the rump, to either get me in the right direction, or to shock me into the reality that “it ain’t possible, bro!”.