The MFOS SCOOP  In This Issue  MFOS Has Parts For Sale
Hi Everyone!

The MFOS SCOOP is being sent at your request to keep you in the loop as far as what is going on at MFOS. If you ever want removed from the mailing list simply ask. I'll try to get something out every month or two. I'll try to keep it informative and useful. MFOS' mission is to be the most informative synth-DIY site on the planet. We're here to help you keep imagining, keep inventing, and stay ingenious!

If you have any suggestions about what you would like to see in an issue of The MFOS SCOOP you can email me at raywilson AT musicfromouterspace DOT com.

Please forward this to any of your friends who have an interest in synth-diy.

This issue of The MFOS SCOOP has some great information. We're always busy trying to design new synth-DIY and electronics projects for you. The Synth DIY Experimenter PCB is gaining popularity with noise musicians and sound effect lovers. It's a great board with a ton of features. The new Swiss Op Amp Knife PCB is a pleasure to use. If you're tired of messing around with those crappy, single sided, junky phenolic boards this is for you. I'm selling precision resistors for the Quantizer and Volts Per Octave Calibrator projects now! And lastly if you haven't checked out the Coffee Shop Web Apps you might be in for a pleasant new diversion.

The Synth-DIY Experimenter PCB
The Swiss Op-Amp Knife
Check Out The New Combo-Paks
Coffee Shop Web Apps
Improve Your Soldering Skills


Finding all of the parts MFOS has for sale is easy on the new MFOS website. Just click the search icon (magnifying glass) and enter parts into the Search for keyword(s) text box, click the search button and up comes the current list of available parts.

  • AD633AN Analog Multiplier
  • Precision 0.1% 100K Res.
  • Precision 0.1% 200K Res.
  • SSM2210 Matched Pair NPN
  • PT094 Tempco
  • PN4391 N-Channel JFET
  • MPF102 N-Channel JFET
  • NJM13700D (LM13700)

NEW! Metal film tempcos are on the way! Stay tuned for more excellent parts for your projects.

  The Synth-DIY Experimenter PCB Is A Great Sound Effects Project! Back to Top  
This project helps creative electronics hobbyists who have successfully completed the WSG learn more about synth-diy. You make "patches" with the Sound Effects project by patching the various "modules" together, and adjusting knobs and switches.


Multi-track demonstration of sounds you can expect (reverb has been added during mixdown):
SDIY Experimenter Board Opus 1 (Ray Wilson)

A *.sfz compatible soft-synth and Web SFZ Helper and you can make multi-track songs using voices you create with the Synth-DIY Experimenter PCB project:

Dance of the Sugarplum Fairy (Peter Tchaikovsky)

The Synth-DIY Experimenter PCB contains some of the first synth circuits I started experimenting with when I first go into synth-diy. You don't have to build all of the modules. You can just build what you want to make a specific sound. You want wind... just build the White Noise Generator and one VCF. You want better wind build the White Noise Generator both VCFs and the output mixer. How about birds or bell sounds... just build the Sound Effect Oscillators an AR Envelope Generator and an LFO. You can go as far as you like with this project.

  The New MFOS Swiss Op Amp Knife. Pamper Your Kludge! Back to Top  
The Swiss OpAmp Knife is for when you have an idea that requires some op amps and associated components and you want a quick PC board to accommodate the circuitry and you can't stand the thought of putting one of those phenolic single sided pieces of junk into your hand-crafted synth. I love this PC Board and putting together quick glue circuits has never been quicker or more convenient.

This product is definitely for you more seasoned hobbyists who already have ideas for op amp circuits and just need a quality place to put them without having to etch a board or use a low quality single sided phenolic kludge board.

  Check Out The New Combo-Packs! Back to Top  
The Quantizer PCB and Precision Resistors Pack This combo comes with the MFOS Quantizer PCB and (10) Precision 100K Metal Film 0.1% 1/4W 50 ppm Resistors and (17) Precision 200K Metal Film 0.1% 1/4W 25 ppm Resistors. This saves you the time of sorting your 1% metal film resistors for 0.1% tolerance since these are already 0.1% tolerance resistors.

The Volts Per Octave Calibrator PCB and Precision Resistors Pack This combo comes with the MFOS Volts Per Octave Calibrator PCB and (2) Precision 100K Metal Film 0.1% 1/4W 50 ppm Resistors and (4) Precision 200K Metal Film 0.1% 1/4W 25 ppm Resistors. This saves you the time of sorting your 1% metal film resistors for 0.1% tolerance since these are already 0.1% tolerance resistors.

  Coffee Shop Web Apps Back to Top  
Web Schematic Now you never need to send someone a scrawled schematic again unless it's your trademark. Web Schematic is a tool that goes wherever the Internet goes. Coffee shops, schools, universities, up in the club, wherever! Web Schematic lets you capture a schematic and save a serialized version of it to share with friends or work on later. Print out your schematic as a PDF. The on line help will have you up and running in no time. Works with most major browsers.

Web Panel Designer Now if you have your laptop you can work on your synth-diy hobby, passion, or job wherever you are: the office, the coffee shop, your deck. Kick around module panel ideas with your friends don't let that cool idea get away. Get creative, get humorous, whatever! Print out your panel idea as a PDF. The on line help will have you up and running in no time. Works with most major browsers.

Web SFZ Helper If you have never heard of *.sfz files and you play soft synthesizers while using your computer recording setup you will be glad you discovered them. It is the standard for soft-synth sample file format that allows you to take any wave (*.wav) files or any Ogg Vorbis (*.ogg) files and play them with your soft synthesizer.

Web SFZ Helper helps you experiment with *.sfz files. The interface helps you set some common settings for the pitch, filter, and amplifier using slider controls. I have provided some sample wav files below but you can use your MFOS synth equipment to make all the unique samples you want and then play them on your soft synth. The *.sfz file format makes it really easy and this little interface makes it even easier!

  Improve Your Soldering Skills by Ray Wilson Back to Top  
Knowing how to solder well is an important part of electronic assembly. A good solder joint can last for decades and a bad one can cause problems at the worst possible time. How can you make sure your solder joints are high quality? It's important to have a good temperature controlled soldering station. You can pick up a good temperature controlled solder station for well under $100.00 from several electronic suppliers. I like to set the temperature to about 650° (343° C) to 750° (398° C) degrees Fahrenheit depending on what I'm soldering. When I'm soldering components I go with between 650 and 700° F and when I'm soldering front panel components I'll crank it up to 750° F.

The solder you use is very important. I use a rosin core tin lead (60% tin, 40% lead) solder sized between 0.025" and 0.06". Some people prefer (63% tin, 37% lead) solder and either will do fine. The thinner solder is great for soldering components to the board. The thicker solder is great for panel wiring. Rosin core is a must. The rosin boils out of the solder and cleans the surfaces about to be eutectically bonded.

It is important to keep the tip clean so make sure you dampen (don't soak) the sponge in the station and wipe the tip on it often. The brass curl cleaners are also good and I regularly use both. I also make sure the tip is tinned well. So before soldering a few joints I'll poke the tip in the curls, wipe it on the sponge and then tin the tip with clean rosin core solder. You don't want a drip of solder hanging off the tip just a coating of clean solder to transfer the heat to you work. Re-clean and tin the tip every ten or so joints.

When you apply the soldering iron tip to the work do it so you contact the PCB pad and the component lead at the same time and then apply the solder to the junction of the tip and work. The solder should immediately melt and flow into the joint. Don't move the work during soldering and don't overheat the joint. Once the solder has flowed remove the iron and let it harden without jostling the work. A good solder joint is shiny and has a concave fillet and does not look like a gray convex bump. If your soldering results in a gray bump get out the desoldering braid. Believe me desoldering braid works and learning to use it is important. Solder suckers have their place but they can also suck the pads right off of your board so be careful. Desoldering braid comes in many sizes and I recommend getting a few different sizes to deal with the various things you will need to desolder. The 1/10" wide stuff is good for component lead desoldering the 1/4" stuff is great for pot and jack terminals. When removing a component cut the leads and try to leave a length to grab with tweezers. The tweezers are also important and a nice sharp stainless steel set is what you want. Grab the lead you want to remove from the board in the tweezers and then apply your solder iron to melt the solder. You need to simultaneously melt the solder and gently pull the lead so that you remove the lead from the molten solder. Do not put unnecessary force on the lead and if the solder hardens STOP and re-melt it or you will end up pulling up a pad or land. Well now the part is removed but the plated through hole is still full of solder. Now what?

Unroll a couple of inches of braid (I use the spool as a handle) and lay the braid on the pad you want to desolder. Now apply the soldering iron tip so that it gently pushes the braid into the solder you want to remove. You may need to lightly tin the tip beforehand so that the heat is transferred to the braid which in turn transfers the heat to the solder, melts it, and soaks it up like a sponge. You may also need to apply some rosin flux to the braid beforehand to give it more affinity to the solder. As you apply the soldering iron watch the braid carefully. You will see the solder flow into it and it will turn silver as it soaks up the solder. Now pull away the soldering iron and the braid simultaneously. The hole should be clear. However things being the way they are that is not always the case. Sometimes you have to actually refill the hole with solder and try again. Always cut off the section of braid that is filled with solder so you go at the next joint with clean braid. With a practiced light touch you will find that you desolder the holes the first time 95% of the time or so. It seems that the harder the pad is to reach the higher the probability that the pad will give you grief. Darn that Murphy.

Desoldering braid has resin in it and usually makes a bit of a mess on the board but it's nothing you can't clean up quickly with some good flux cleaner and an acid brush. Acid brushes have tin handles and horsehair or nylon bristles are cheap and are able to stand up to the chemicals used to clean circuit boards. My all time favorite cleaner is TECHSPRAY Econoline FLUX REMOVER. It has all the good "green" attributes but still cleans up rosin and soldering residue perfectly. When cleaning up my work I will use the thin tube that fits into the spray nozzle and carefully spray a bit into a cap from a two liter bottle and dip the acid brush and gently scrub the area that needs cleaned. Wipe the brush on a rag, re-soak the brush and clean again. Finish up by actually spraying the area with the flux remover and letting it dry.

I hope these tips help you improve your soldering. Cheers, Ray