DIY Factory - daw monitor switcherl 2

DIY Factory

Daw Monitor Switcher Project Mk3
A project brought to you by Mikkel and Kev.
A project brought to you by Kev and Mikkel C. Simonsen .
Updated 28 December 2005

General Description

A simple DIY Monitoring Unit that uses a multi relay board to take the place of the usual stepper attenuator switch.

The advantages of using a a relay board over the stepper switch is that the signal path can remain in the equipment rack and the remote conrol is all that is needed on the work surface.
This can keep signal paths short and away from CRT monitors and also keeps the work surface clear of much of the cabling that otherwise would be required.
The remote control can potentially be infra red if you are keen. I prefer to have a hardwire connection. A simple CAT5 cable should do nicely and is an easy option to live with.

many thanks to Mikkel Simonsen for all his help and work in putting some of his existing kit PCB's to work in a blah blah

Mikkel's kits web page can be found at
http://electronics.dantimax.dk/Kits/index.html

http://electronics.dantimax.dk/Kits/index.html

below is simply a reprint from Mikkel's site

VolControl
Volume/attenuator control board kits

These boards are combined front panels and CPU boards. They can be used to control one volume control/attenuator board.

The controls consist of a rotary encoder to set the volume level, and an IR sensor for remote control operation. The VolControl1 board does not include a display, so there is no indication of the volume level. The VolControl2 board includes a 2-digit LED display, and the VolControl3 board can control an LCD display. Otherwise the boards are identical.

The board needs a regulated 5V supply (a 7805 regulator for instance). The sizes are 70*27mm (VolControl1), 99*33mm (VolControl2) and 67*35mm (VolControl3).

For displays suitable for the VolControl3 board see the "Accessories" section.

RelVol1 and RelVol3
64-step relay attenuator kits

RelVol1 and RelVol1C are are stereo attenuator boards made using relays and precision resistors. The RelVol3 board is a balanced version of RelVol1. The "C" version includes a control section with a rotary encoder and remote control receiver. The standard versions can be used with the different "Control" and "VolControl" boards.

The attenuator is normally setup with 64 1dB steps, but other step sizes like 1.5dB are also possible. The attenuator has a constant input impedance, and any impedance value can be delivered at no extra cost. Standard values are 5k, 10k, 20k, 50k and 100k.

The kits are available as complete kits and PCBs only (both come with manuals/part lists). Resistor kits with MRS25 1% resistors are also available - two kits are needed for a RelVol3 board.

The boards need a +5V supply. The non-C versions can be supplied by the input selector board (if one is used). The board sizes are 75*83mm (RelVol1), 75*93mm (RelVol1C) and 89*75mm (RelVol3).

Note: The delivery time on the RelVol3 kits is currently approx. 2 weeks.

I designed the RelVol1/3 circuit in the winter of '03/'04. But I was not the first to design this circuit. Alex Nikitin of A.N.T. Audio designed the same circuit more than two years before me (which I didn't know until recently). He describes the circuit here. When looking through that thread, it looks like others have "invented" the circuit also :)

more text to come

Parts List
if there is one

Downloads

if there are any

Pics

ERRATA

So far so good. Check back for any updates in this area.

Contact :

this page is still under development
and more will be added

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