BookTip XIV: Electronica for Dummies (Dutch Edition)

Electronics for Dummies, Dutch Language version

Okay, a bit of a weird BookTip this time... at first sight.

The For Dummies series is an extensive series of instructional/reference books which are intended to present non-intimidating guides for readers new to the various topics covered.

As of December 2012, over 1800 For Dummies titles have been published with editions in numerous languages.

This Electronica (electronics) edition (published in 2005 in multiple languages) is extremely useful for the beginning electronics DIY-ers (like me), and it has already been very helpful making thing more understandable.

The book (416 pages) covers a whole range of subjects, from the basics, preparation, tools and safety-measures to easy-to-build small projects on a breadboard or with self-made printed circuit boards (pcb's).

On your way through the book you'll learn everything about diodes, resistors, capacitors and reading schematics. It even has a robotics section...

I learned a lot from this book so far, although i haven't even read it all... i mainly use it for reference.

In the English language you have the choice of a few different books about this same subject in the For Dummies series,

Closest is probably the Electronics All-In-One Desk Reference For Dummies, and for the advanced DIY-ers I guess they could even try the Circuitbuilding Do-It-Yourself For Dummies, but please check before you buy because i'm not sure.

More info at http://www.dummies.com/

Written by: Gordon McComb & Earl Boysen

ISBN: 978-90-430-1162-4

Find my other BookTips HERE

A-136 Pre-amp Modification

I discovered another nice light-weight DIY-project on the Doepfer DIY-page.

Locating the R2 resistor

It seems that the A-136 Distortion/Waveshaper module contains an internal pre-amplifier that is used to amplify the input signal by about 3.5 before it is processed by the A-136.
Especially for low level audio signals (e.g. output from a VCF) this is useful.

But for all signals with a level beyond ~ 7V this causes clipping before the internal processing takes place. 

Especially for the processing of LFOs or unfiltered VCOs this may cause a problem.

The wiring, additional pictures
on the PatchPierre Facebook page

To totally bypass the internal pre-amplifier, resistor R2 can be removed (e.g. by pinching off).

R2 is the resistor in the upper third of the pcb which is very close to the rear edge.
When R2 is removed the amplification of the internal pre-amplifier becomes "1" (which means that it does no longer amplify).

Finished modified A-136 

Because i love to keep myself busy (I'm slightly ADD-ish), i decided to add a switch to the module, so i can switch between pre-amplifier on and off modes.
It looked like an easy project, so... what could go wrong? ;-)

Besides the front-panel it was a pretty easy job;
I desoldered one side of the R2 resistor, bent it over towards the switch, and wired it with black wire.
After that i soldered another wire (red) from the switch to the hole where R2 used to be. Easy as that.

Now i can manually switch the internal amplifier on and off when required.
The clipping did annoy me at times and now i prevent that and try the un-amplified signal with alternate settings*.
it's not a groundbreaking project, but a nice extra.

* In addition one has to pay attention that the knob positions may vary a bit from the front panel printing because of mechanical tolerances of the potentiometers and knobs (i.e. "0" is not always exactly the neutral position for "A", "+A" or "-A")

The modifications described on this site will most likely void any warranty and, if not done carefully, can damage the circuit board, IC chips, and faceplates.
PatchPierre can not be held responsible for any damage.

Happy Modding II - Joystick Spring Removal

The A-174 Joystick Controller outputs 2 control voltages, generated by a spring-loaded X/Y cross potentiometer.
Two springs inside the module take care that the controlling lever returns to it's centre position if untouched.

One very easy modification is the removal of a spring from this module


The process of removing is quite simple, and is described clearly on the Doepfer DIY page / section 4.2.10.

I decided to remove one spring only, the horizontal one. ( X-axis )
This way the Controller stays fixed, even if i let go of the lever, and doesn't automaticly go back to the middle.

If you do this to the Y-axis ( vertical ) of the module, the lever would fall down to it's lowest position due to gravity, which also can be handy in some situations, but not mine at the moment.

This small modification adds just that tiny bit more flexibility to my setup.

Note: Pay attention that warranty is lost if the joystick is modified !

Happy Modding I

One of the easiest, and perhaps the most usefull DIY modifications you can do to your A-100 system is modifying the A-180 module.

Originally the module has 8 interconnected sockets that act as all identical multiples, but like the manual says you can split this into 2 groups of four by removing the soldering bridge in the middle or cutting the board.

The manual doesn't say anything about the warranty if you do this, but just be very carefull.

An easy job, done in a few minutes and like i said very usefull, especially for the smaller systems IMO