Bill and Will's Synth
MOTM 420 Two Dot Oh Construction
"MOTM-420 Voltage-Controlled Filter"

October 2009 -

Why a second MOTM420 page?  Well, we're building another 420, and it's a little different when you're working from a Synth Tech 2.0 thing rather than a full-blown "kit."  So if you feel the need, cross reference this with the KitPage here.

We're going go right into building the thing.

Table of Contents

This page has become really long, so here's a table of contents that we hope will make it easier to traverse:

Parts - presents a Bill of Materials and notes about it

Construction Phase 1 - Resistors, Capacitors, IC Sockets, Power Plugs, MTA headers

Construction Phase 2 - Trimmers, Panel connections

Set up / Testing

Parts

Will and I have developed a parts-list / bill-of-materials in the form of an XL spreadsheet based on the parts list in the 420 User Guide.

Click here to download the XL spreadsheet (apx. 350K).

Click here to download the .pdf Synthesis Technology parts section of the User's Guide.

Click here to go to our Bill of Materials Page.

Construction Phase 1

All the stuff in Phase 1 gets soldered using "Organic" Solder.  At every break in the action, we wash the board off to get rid of the flux.

Resistors, Caps, Power

As usual, whereas we are vigilant about orienting all the resistors, caps, etc. consistently so their values can be read easily (in case we need to trouble-shoot them later), we oriented the resistors with the "tolerance" stripe on the left (relative to the text on the pcb).  We got started doing it this way when we started building our synth and now we do it so all our modules are consistent with each other.  You might want to do it the opposite way - with the "tolerance" stripe on the right.

One of the caps we got is a little fatter than its corresponding spot on the PCB, but we didn't have any trouble fitting it in.

Semiconductors - Misc - Via Holes

We used an IC jack for the 1013 op amp 'cause we weren't totally sure the one we got is correct.  Here it is installed in the jack:

Construction Phase 2

All the stuff in Phase 2 gets soldered using "No Clean" Solder. 

Pots, Wires

the PCB mounted pots and wires

Tempco Resistor

just like that

Construction Done

Set up / Testing

Use Notes