Yet another passive volume control - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 13th November 2014, 12:50 PM   #1
zatra is offline zatra  Poland
diyAudio Member
Join Date: Aug 2005
Default Yet another passive volume control

Hi there,
i wanted to build my own passive volume control, so i started to look into some projects .. and upon them design my circuit. Because i'm an amateur in area of electronics i wanted to show my schematic and kindly ask for an help/opinion. I still need to draw connections for the display and push encoder.

So .. can anyone look into this and give me a hint how to best connect a display and encoder to this and if there are some mistakes(hope not)? Design is based upon atmega328 programmed with arduino.

Click the image to open in full size.

i'm bit better in drawing pcb's .. this is a mockup based on this schematic (shows top layer only)

Click the image to open in full size.

  Reply With Quote
Old 13th November 2014, 05:57 PM   #2
AndrewT is offline AndrewT  Scotland
diyAudio Member
Join Date: Jul 2004
Location: Scottish Borders
why are there 16 relay coils but only two banks of 7 relays in the schematics?
regards Andrew T.
Sent from my desktop computer using a keyboard
  Reply With Quote
Old 13th November 2014, 06:11 PM   #3
diyAudio Member
Join Date: Jun 2010
Location: Germany and
Default Missing things....

.... don't forget to add:
- a programming header for the atmel
- perhaps an JTAG header for the Atmel
- some Debug Pins with LEDs
- perhaps the UART Tx line for debugging purposes....
- Diodes above the coils (Flyback voltage !)
- some small caps (100nF) across the relais coils, to shunt away noise picked up by the relais

Also, don't forget to design your Power Supply so, that if ALL Relais are ON, it can deliver the required current....

Perhaps, you can add the signal to the ADC to detect zero cross.....
Designing audio electronics isn't a job, it's a mission
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Passive Balanced Volume Control Questions SilverStrings Analog Line Level 9 5th November 2011 08:53 PM
Remote control Passive Volume Control with Display ua100k Swap Meet 2 31st May 2011 03:01 PM
Reed relays in passive volume control? hermanv Analog Line Level 24 4th May 2008 03:50 PM
passive line level volume control CharlieM Planars & Exotics 1 9th March 2008 01:43 AM
6c45 and passive volume control? AudioGeek Tubes / Valves 0 16th January 2005 10:05 PM

New To Site? Need Help?

All times are GMT. The time now is 12:29 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2