I am going to move all information related to this project from Zappbots to here on this project, but if I remember, Chris, this is your diagram, yes?
(https://savagechats.com/proxy.php?request=http%3A%2F%2Fjknightelectronics.altervista.org%2FElectImages%2FKITT-KARR-Example.png&hash=487ec04dafcf72d6bf71652006b05d6f3fba4514)
I want to take one of the Q1/Q3 and put a PNP transistor in its place with Green_EN & Red_EN connected together to a single pin with this schematic, ex from PPDB button/switch
(https://savagechats.com/proxy.php?request=http%3A%2F%2Fjknightelectronics.altervista.org%2FElectImages%2FPPDBbutton.png&hash=5b5cc160b168adb3a6c173247b4c8b61fd3ec6e9)
obviously no buttons/switch, but what goes to the mcu on the board, set to input, and buttons to the Q1/Q3 or something to that effect, lol to keep KITT on by default and KARR only when voltage is applied to the terminal.
Will post more stuff, as I can.
Quote from: JKnightandKARR on Dec 06, 2024, 02:14 PMI am going to move all information related to this project from Zappbots to here on this project, but if I remember, Chris, this is your diagram, yes?
Yep. Looks like something I did. ;)
Quote from: JKnightandKARR on Dec 06, 2024, 02:14 PMI want to take one of the Q1/Q3 and put a PNP transistor in its place with Green_EN & Red_EN connected together to a single pin with this schematic, ex from PPDB button/switch
obviously no buttons/switch, but what goes to the mcu on the board, set to input, and buttons to the Q1/Q3 or something to that effect, lol to keep KITT on by default and KARR only when voltage is applied to the terminal.
Soooo, I am a bit confused. ??? All you need to do if you want the default color to be GREEN is to tie the RED_EN to the collector of Q1 and when the input to GREEN_EN is HIGH, GREEN is ON, and when LOW, RED is ON. Unless I misunderstand you. :-\
P.S. - Q2 / Q4 need to be able to handle the current of all LEDs (of that color) being on at once.
Quote from: Chris Savage on Dec 06, 2024, 02:37 PMSoooo, I am a bit confused. ??? All you need to do if you want the default color to be GREEN is to tie the RED_EN to the collector of Q1 and when the input to GREEN_EN is HIGH, GREEN is ON, and when LOW, RED is ON. Unless I misunderstand you. :-\
P.S. - Q2 / Q4 need to be able to handle the current of all LEDs (of that color) being on at once.
Basically, when the terminal is low, the PNP turns on n the KITT display turns on, while KARR is off, and when termimal is high, the opposite is true.
Quote from: JKnightandKARR on Dec 06, 2024, 07:48 PMBasically, when the terminal is low, the PNP turns on n the KITT display turns on, while KARR is off, and when termimal is high, the opposite is true.
Okay, so connect your control signal to RED_EN and connect the GREEN_EN to the collector of Q3.
Game, set, match. 8)
No PNP needed.
Quote from: Chris Savage on Dec 06, 2024, 07:57 PMQuote from: JKnightandKARR on Dec 06, 2024, 07:48 PMBasically, when the terminal is low, the PNP turns on n the KITT display turns on, while KARR is off, and when termimal is high, the opposite is true.
Okay, so connect your control signal to RED_EN and connect the GREEN_EN to the collector of Q3.
Game, set, match. 8)
No PNP needed.
but don't that mean 2 pins to use?
Quote from: JKnightandKARR on Dec 06, 2024, 08:41 PMbut don't that mean 2 pins to use?
Why? Your one pin is connected to the RED_EN. The GREEN_EN is controlled by the RED_EN (INVERTED). One pin does both. When LOW, the LEDs are GREEN, when HIGH, the LEDs are RED.
(https://savagechats.com/proxy.php?request=http%3A%2F%2Fjknightelectronics.altervista.org%2FElectImages%2Fvbmod.jpg&hash=db9a701dea6ad94930db552d28908cfa9f9c1970)
Like dis??
Quote from: JKnightandKARR on Dec 06, 2024, 11:30 PMLike dis??
Yes. Now when the control signal is LOW, the RED LEDs will be OFF. However, R4 should be enough to enable Q1, which will turn ON (turning on the GREEN LEDs). Using the system in this way may or may not prompt some minor changes, such as removing R1, since you're not directly driving the transistor and changing R4 to 4.7K. Again, these changes may not need to be made, but I don't have SPICE installed on this PC to see the effects of the changes. Logically, they would seem to work without adding any new parts.
By the way, if you're going to be feeding an audio signal directly into the input to the LM3914, I would first run it through an op-amp and then through a diode, followed by a resistor / capacitor in parallel with the signal to buffer it slightly to make it look more responsive.
Got it thanks!
Quote from: JKnightandKARR on Dec 08, 2024, 10:46 AMGot it thanks!
I will get you the details for that soon. I would normally point you to my Audio Level Meters (https://savagecircuits.com/audio-level-meters/), but I need to first recreate the schematic (it's missing).
Ok, i do have one myself btw
Schematic for audio meter.
Quote from: JKnightandKARR on Dec 09, 2024, 09:24 AMSchematic for audio meter.
Oh. Well, I remember when I was younger building the "VU Meters" circuit right from the dayasheet. I remember thinking to myself that the response was horrible and didn't look anything like the VU meters on my audio equipment. So I designed my own buffer that I always use so the meters flow better. Anyway, that's all I meant. But if you have something you're happy with, definitely use that. Once I rebuild mine, I will be posting a video of them in action.
As a note, since the LM391x parts are obsolete now, it really doesn't make much difference. It's not feasible to think they could be used for mass production.
That's another reason I did one with an Arduino Uno... not the best display, but i saw the 3914 think been discontinued, think i got 3915.. if have another option I am all ears!
Here's my attempt... responce is VERY bad...
December is the busiest month for me as far as holidays, birthdays, events, etc, not to mention still working on the new house. But I'm planning on getting content updated after the holidays (New Years). One of the things that should be quick and easy is to redraw the schematic for the Audio Level Meters. I am making a priority list so I can maximize my time and wrap things that only need new photos or minimal updates. Perhaps that schematic will be of use to you in the future.
Ok, I been doing research on other options myself, inc thinking about trying to translate my arduino code onto the propeller and see if I can make it work better on there.
Edit: I think maybe the code I used on Arduino might have been the issue.. I was trying to find the code, must have lost it somehow..., random opening example to locate the ext to search for, and they already have a bargraph example, which I'll try and see if that works any better, esp with the buffer circuit you mentioned.
Quote from: JKnightandKARR on Dec 10, 2024, 11:35 AMrandom opening example to locate the ext to search for, and they already have a bargraph example, which I'll try and see if that works any better, esp with the buffer circuit you mentioned.
The circuit / buffer I mentioned is more or less a poor-man's "peak hold" for VU meters. Let me explain...
Since the audio signal is an AC waveform, the default level meter circuit is very jittery as the waveform jumps very quickly from its peak value to zero (or negative in many cases). The circuit I created rectifies (using a single 1N914 diode) the audio to grab only the positive portion of the AC signal, then uses a 0.1µF capacitor and 1MΩ resistor to "buffer" that signal, causing it to "hold" longer. The effect is that the VU meters are more fluid and responsive. If you're doing this on an audio switcher or pre-amp, you would want to use an op-amp to buffer / isolate the source audio and you may want to provide an adjustment to calibrate the signal for peak reading on the meters.
Thanks Chris. I planned on an adjustment already. That might be why my video is bad on performance/the program I used could have been an issue too... I will try the program in the Arduino library, that should fix any issue with that, and will try your circuit too.