EFM R&D

[tomg]

Lately there has been some interest here and in my personal mail
concerning the amount of work I am getting done and how I'm doing it.
Thanks for all of your comments, congratulations and criticisms. Let me assure
all of you it has not always been this way. I don't have any special talent.
It's hard work paying off. EFM is the product of two years of hard core r&d.
It has been almost exactly two years since I decided to build my first synth
and five synthesizers later I am just starting to get the hang of it. Most of
you guys are professionals so my equipment list and procedures will seem
elementary to you. I'm just a guitar player who learned to fix things and
decided to build a synthesizer. BTW I'm just getting started good. I only have
so much cash for parts. And I wish I could work faster...:-) 

As to why I'm doing this. I just want to build myself a few really good
synths. I really don't have to, I have a ton of cool gear, I just want to.
Hanging out with you guys helps a lot. Thanks to all of you for being here.
Finding SynthTech was the answer to a prayer.

Development Environment.

) Lots of free, quite time. I have the wife most men dream of. 
) I am a very, very lucky man.

) My office/studio.
) My beloved Amiga 3OOO (I have Macs and PCs too. No Flames Please.)
) A huge collection of reference books, manuals and magazine articals.

Equipment List (Just the synth r&d stuff.)

) Homemade +-12V at 1A/+-5V at 1A/+-O to 28V at 1.5A/+-35V at 5A power supply 
) internal 1 watt monitor amp on a separate +12V PS .

) Homemade Synth r&d box internal VCO VCF VCA EG.
) Homemade 6OW current limiter with internal variac.
) Homemade 8O38 based function generator.
) Micronta 22-195 digital meter
) Micronta 22-188 digital meter
) Micronta 22-2O2U multi meter
) Micronta 22-2O9A fet-vom
) BK 1803 1OOMHZ frequency counter
) Hitachi V-212 2OMHZ dual scope
) Eico 1120 cap box
) Eico 11OO resistance box
) Weller TC-2O2 power unit 24V 42W iron 
) Wish Board 2O6 prototype board 26OO+ tie points 18 ic capacity

) It helps to have a large supply of parts. I have been collecting
) stuff for 1O years. I have one of most things. That's what
) happens if you always buy two. BTW I found those top octive chips. If
) you are the one who needed it mail me. I can do better than $40.

Research Procedure.

) Have a idea, or borrow one. If I borrow, I borrow from the best and
) give them credit. That means I'm always giving credit to someone
) else. Who said "I stand on the shoulders of giants."? I need to borrow 
) that too...:-)

Development Procedure.

) Hand draw the circuit. (This is an important step)
) Proto-board the circuit note voltages at critical points. Note changes.

) I understand not everyone likes the proto-board part. But you test the
) design and the parts together. Saves me tons of time.

) NEW ADDITION-> Make parts list. It must be harder to read values online
) than I thought. Everybody wants parts lists.

) Cad the schematic diagram and pc-board layout. Note changes.
) Build a perf-board version. Note changes.
) Correct Cad drawings. Note changes.

Do you get the idea I take a lot of notes?

I have not preceded to the next step in a long time. At this point I'm
ready to mount whatever it is it on a piece of aluminum angle and put knobs on
it. It's also at this point I usually post it on my site and
wait for people to ask if it works or not.

) Print final board transparency.
) Expose, etch, drill, clean and mount parts on the pc-board.
) Final assembly.

) About every six months I take my drawings and printouts to the
) local copy center and have them bound. They become referance books.

I hope this helps the interested and doesn't bore everyone else.

-Tom