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Arduino based LDR volume and source selection controller
Arduino based LDR volume and source selection controller
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Old 21st September 2015, 11:33 PM   #11
monty78pig is offline monty78pig  England
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Arduino based LDR volume and source selection controller
Cool design. Wondering what the benefits of LDRs are over conventional active volco chips such as the PGA2311? I remember reading that they produce a small amount of distortion as current rises through them, although I have only ever used them in instrument compressors where it's not an issue. Matching them was a bit of a pain though for stereo .

Maybe this thing could be put inside the power amplifier as well, that Arduino could be put to good use as a muting control at startup and a heatsink temperature monitor.

The possibilities are endless! Nice PCB BTW !
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Old 22nd September 2015, 04:37 PM   #12
jackinnj is offline jackinnj  United States
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Arduino based LDR volume and source selection controller
Quote:
Originally Posted by monty78pig View Post
Cool design. Wondering what the benefits of LDRs are over conventional active volco chips such as the PGA2311? I remember reading that they produce a small amount of distortion as current rises through them, although I have only ever used them in instrument compressors where it's not an issue. Matching them was a bit of a pain though for stereo .

Maybe this thing could be put inside the power amplifier as well, that Arduino could be put to good use as a muting control at startup and a heatsink temperature monitor.

The possibilities are endless! Nice PCB BTW !
Only issue with PGA2311 is to separate the analog and digital ground plans -- as seen in the data sheet. I would guess you would want an interrupt so that you aren't continuously clocking the device.

I did some analysis of the Silonex, Vactrol and Fairchild several years ago:
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Old 26th September 2015, 08:34 AM   #13
wineds is offline wineds  Australia
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This is very nice work Vincent. Seriously considering attempting a build.
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Old 26th September 2015, 09:06 AM   #14
wineds is offline wineds  Australia
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Could you possibly post photos of the input and power supply pcbs?
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Old 26th September 2015, 10:05 AM   #15
jps1964 is offline jps1964  Germany
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Hello Vincent,

Ive only one objection in your design: the use of the chinese display; it is not really long term availability and for some people really hard to purchase.

My idea is to modify your design by adding a LCD touchscreen display over the I2C interface (A4 and A5 pins from Arduino): one board with C, LDR, IOs interconnected with a 1mm ZIF connector, or other type, to a second board with supplies and LCD (the encoder is superfluous).

The candidate for this display would be from ELECTRONIC ASSEMBLY. Ive used successfully this type of LCD with touchscreen in military application, but sorry, Im not programmer!

They provide also OLED displays but in this case only over SPI.

ELECTRONIC ASSEMBLY - root LCD Module

Ok, you have to do some firmware modification to implement the LCD.

I know that a lot of people will then positivelly interested in a GB...

Regards,
Jean-Paul
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Old 26th September 2015, 02:22 PM   #16
jackinnj is offline jackinnj  United States
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Arduino based LDR volume and source selection controller
Over here, Mouser and Sparkfun Electronics carry the resistive and capacitive touch screen displays from 4DSystems.
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Old 26th September 2015, 04:41 PM   #17
jps1964 is offline jps1964  Germany
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? Bad question?

Is the LDR on the resistor polarized? Can I swap the pins?
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Old 26th September 2015, 05:50 PM   #18
jps1964 is offline jps1964  Germany
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... ongoing...
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Old 27th September 2015, 12:24 AM   #19
wineds is offline wineds  Australia
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Quote:
Originally Posted by jps1964 View Post
? Bad question?

Is the LDR on the resistor polarized? Can I swap the pins?
yes you can. the resistor part is not polarised.
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Old 27th September 2015, 12:53 AM   #20
jps1964 is offline jps1964  Germany
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@wineds

Thanks!

Finally with wired RCA CINCH connectors and AMP MICROMATCH interconnection.

ZIF socket to missing third board with LCD.

More to come...

Good game Wales!
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