Monthly Archives: January 2010

First Production Volume Box

Finally I have all the parts and I spent last night assembling ten boxes to fill my first order. It looks not half bad.

Next I need to set up a web page and finalize pricing so anyone can buy one.

So what is a Volume Box I hear you ask? Well, the Volume Box is a digital stereo volume control. It has no knobs or buttons, it is controlled via serial commands from a PC or home automation system. It is intended to be used as a component in an automated audiovisual setup such as conference centres, classrooms etc.

Features include:

  • Attenuation from 0 to -95dB in 1dB steps
  • 3 way stereo input selector
  • Line level inputs and outputs
  • Optional 7 watt power amplifier
  • Mute function
  • Preset store and recall

Volume Box is Almost There

VolumeBoxPlugs-smallI’m getting orders for the Volume Box already. I haven’t even put up a web page for it. But wouldn’t you know it, the plastic case I want is not in stock with any of my regular suppliers (at least, those ones who are not still on extended Christmas holiday) so I’m having to get some cases flown in from England of all places so I can fill the orders. Of course I am going to have to absorb the extra cost of that, I wonder if Sony ever has these kind of supply-chain problems.

First Prototype Volume Box

The first completed unitThe Volume Box board is assembled and tested, the last few firmware bugs are squished and the only thing missing now is the machined end panel for the plastic case and it is ready to sell!

Here are the lessons I have learned:

1. PICs can be a mighty pain in the bum to debug, particularly the peripherals. I think I’ll use a different chip next time.

2. Always check your component footprints when designing a PCB, the Protel footprint libraries are full of errors. I’ll be patching the first run of boards due to a bad footprint.

3. Don’t try to get a product out the door around Christmas time, many manufacturing companies are closed for the holidays especially here in Australia where we combine our summer holiday and Christmas holiday into one big long holiday. Some companies do not resume business until January 18th!

Anyway, now the design is proven I have ordered some parts to begin producing these things.