Good to see some version back, if only in proto form.
Roger's gonna roll his eyes; I've said it privately enough times I'm sure: why does anyone need a 20 dB GR point on a meter? I'd always rather have great resolution near the threshold versus extended range. Once you're past 10 dB GR, the meter doesn't really matter any more. What goes on between 0 and -2 does matter a great deal to me, as it helps determine the best threshold. I am probably a minority.
THAT1646 Current Booster and Transformer Driver
Re: THAT1646 Current Booster and Transformer Driver
Best,
Doug Williams
Electromagnetic Radiation Recorders
Doug Williams
Electromagnetic Radiation Recorders
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Re: THAT1646 Current Booster and Transformer Driver
To prove it can go to "11?"why does anyone need a 20 dB GR point on a meter?
I do notice this GR has 2 dB steps which is cool.
Roger did you use a comparator string to get the 2 dB steps? Or just drop the intermediate steps on an LM3914 to make that jump from 10 to 20 dB?
I like the simple three-knob approach.
- mediatechnology
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Re: THAT1646 Current Booster and Transformer Driver
I do like those square LEDs.
The red hex screws are a nice touch.
The red hex screws are a nice touch.
Re: THAT1646 Current Booster and Transformer Driver
Back when I designed dynamics processors (a long time ago), I oriented VCA status meters to indicate gain reduction going down, and gain boost up. Of course this was in an odd-ball full range compressor that boosted low level stuff that was below threshold, and dropped high level stuff that was above threshold, not too mention added parallel downward expansion/noise gating... and more, perhaps too much.
Your display effectively communicates how much the signal is squashed, with higher is more, all good. The customers generally like all blinky lights.
====
Agreed the rectangular LEDs look better to me too...
The painted allen head screws are a nice detail but almost look like indicators. The rectangular LEDs reduce the potential for confusion.
JR
Your display effectively communicates how much the signal is squashed, with higher is more, all good. The customers generally like all blinky lights.
====
Agreed the rectangular LEDs look better to me too...
The painted allen head screws are a nice detail but almost look like indicators. The rectangular LEDs reduce the potential for confusion.
JR
Cancel the "cancel culture", do not support mob hatred.
Re: THAT1646 Current Booster and Transformer Driver
That's funny, I remember some angst over the options with a reduced number of LED's. Today I'd probably vote 1/2/3/4/6/8 or 10. Tomorrow?raf wrote: this meter implementation is one Doug suggested many moons ago. It uses a standard LM 3914 and skips the intermediate steps.
Best,
Doug Williams
Electromagnetic Radiation Recorders
Doug Williams
Electromagnetic Radiation Recorders
Re: THAT1646 Current Booster and Transformer Driver
I have been kicking around the idea of making an universal meter chip based on a microprocessor... It is almost easier to make a big meter effectively than a small one. The rap against the 3.3V micro family I like is that they don't look like they can drive bare LEDs adequately, but i suspect modern high efficiency LEDs could probably work. For large scale meters, simple to drive a latch IC.
While it is hard being all meters to all people, i could pretty easily support an optional linear scale, or even a proportional log scale where the step size between LEDs is read in from a pin. Say you divide the PS by some fraction and feed that into an A/D input. The micro reads that voltage, determines the ratio of the 3.3V supply, and makes that the ratio between each LED down as far as it can.. Easy to make 1dB, 2 dB, whatever dB steps down to the resolution floor of the A/D.
This us not worth killing a lot of brain cells over but i have a sweet PK/VU technology I have in the can to use. I'f love to make a generic swiss army meter (in my spare time)
JR.
While it is hard being all meters to all people, i could pretty easily support an optional linear scale, or even a proportional log scale where the step size between LEDs is read in from a pin. Say you divide the PS by some fraction and feed that into an A/D input. The micro reads that voltage, determines the ratio of the 3.3V supply, and makes that the ratio between each LED down as far as it can.. Easy to make 1dB, 2 dB, whatever dB steps down to the resolution floor of the A/D.
This us not worth killing a lot of brain cells over but i have a sweet PK/VU technology I have in the can to use. I'f love to make a generic swiss army meter (in my spare time)
JR.
Cancel the "cancel culture", do not support mob hatred.