Hello, newbie here. - Page 1
Forum section: electronics / beginners

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 08:12:08 pm
content: Hello everyone, I didn't see a "Welcome Wagon" or "Introductions" sub-forum, so I figure this is a good place to introduce myself -- since I am a beginner.My background is in Software Engineering, but I know a bit about digital electronics. As a college project we built an 8 bit CPU with an 8 bit address space, simulated in LogicWorks -- this was back in 1994 wow.I've played around with Arduino a bit (since I am a programmer I find the C programming language of the arduino quite approachable -- have written lots of C code among many other languages). I made a MIDI controller with arduino and did a few other projects related to the digital realm -- simple. Played around with some sensors reading data on the analog ports.However, I've never sat down and built a circuit with things like transistors or op amps. I am excited to get into this area. [About the only thing I have built that isn't digital related are a couple linear power supplies.. one for DIY LM3886 home stereo amplifier and another for my old commodore 64. I understand how transformers, rectifiers, filtering caps work at least.]I like music and I play a few different instruments. I've always liked synths, so that's the area I want to focus on.Working on making my own modular DIY synthesizer. I think I'll start with Thomas Henry's VCO-555. But I want to first build very basic stuff, learning things, one baby step at a time. I have no idea how the VCO-555 works as I look at the schematic now. Lots of op amps and the 55 timer. Tons of resistors, caps & transistors. So I just have to learn one thing at a time, starting with single transistor circuit or single op amp circuit etc. Just bought Forrest's Op Amp Timer book -- maybe that'll teach me the basics. Well there is also google & youtube and this forum which is niceI just bought a used Fluke 8050A for like $30 shipped which is the version without the battery fortunately and the LCD works as well. Hopefully the meter won't need calibrating.. should at least be better than all the $5 multimeters I have laying around the house. Also bought an HP 6236B Triple Power Supply which I hear is great for making synth modules.Better late than never I guess!

author: MagicSmoker
author_rank: Super Contributor
timestamp: February 23, 2017, 08:22:36 pm
content: Those Forrest Mims books are classics and make handy quick-reference guides, but if you want a bit more explanation covering a much wider range of topics while still being approachable then I highly recommend forking over the dough for The Art of Electronics by Horowitz and Hill.Analog synths are fun stuff to build and try out. It's one of the few areas in electronics where doing things wrong can turn out alright

author: cvriv
author_rank: Frequent Contributor
timestamp: February 23, 2017, 08:26:42 pm
content: Hey.

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 08:43:55 pm
content: Quote from: MagicSmoker on February 23, 2017, 08:22:36 pmDo you recommend the 2nd edition or 3rd edition? I just read someone's review of 3rd edition and said they didn't like that they removed the circuit building section at the end of each chapter. He said that practice is as important as theory and that they shouldn't of removed it.

author: rstofer
author_rank: Super Contributor
timestamp: February 23, 2017, 08:55:10 pm
content: Now there is a companion volume "Learning The Art Of Electronics" that deals with the lab exercises and gives a lot more explanation. Highly recommended... FWIW, DigiKey has bundled the parts kit (I don't know if it is 100%)http://www.digikey.com/en/resources/edu/harvard-lab-kitIt seems kind of pricey for the hobbyist but if I was going to Harvard, I would have my parents buy it in a heartbeat. Alas, I'm retired and if I want it, I'll have to pony up the bucks! So far, I have resisted but sooner or later I will get more interested.As to the VCO-555 circuit, look inside the 555 and see what it does. Basically, it is a pair of voltage comparators connected to a set-reset flip flop and an output driver. Here's a pretty good description.https://en.wikipedia.org/wiki/555_timer_ICNow you can look at the rest of the circuit and see how it manipulates the TRIG and THRESH inputs.Oh, and welcome aboard!

author: PartialDischarge
author_rank: Super Contributor
timestamp: February 23, 2017, 09:12:41 pm
content: Quote from: JenniferG on February 23, 2017, 08:43:55 pmThe 3rd, totally, no question. Besides including sections on a variety on new topologies and components, explanations are better

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:13:52 pm
content: What do you think about using a SPICE program to learn all these lab circuits in this Learning the Art of Electronics book? I read something about LTSpice, but that is an older program. Is it still considered the best free SPICE program? Or are there better ones? Or perhaps I should spent a little for a better SPICE program. That's a lot of parts to buy if I do it physically.

author: MagicSmoker
author_rank: Super Contributor
timestamp: February 23, 2017, 09:22:44 pm
content: Quote from: JenniferG on February 23, 2017, 08:43:55 pmAh, yes, the "good and bad circuits" section at the end of each chapter in the 2nd edition was quite valuable, and did go missing in the 3rd edition. However, the 3rd edition has a lot more content and most of it seems to have been updated (I haven't read it cover to cover, though; I mostly use it as a reference).Still, I would give the nod to the 3rd edition because clear yet comprehensive explanations of electronics are hard to come by while circuit ideas (bad and good) are a dime a dozen.As for SPICE, I like/use Tina and LTSpice. Tina is better at general purpose simulation, is easy to learn/use, and not terribly expensive (I think there is a free version, but it might be crippled or specific to TI parts only?), while LTSpice is quite specialized at switchmode power supply simulation; it is also free, so that's definitely a plus. LTSpice is up to date, but it has a somewhat arcane user interface (sadly, that seems to be the case for all electronics-related programs), so not as easy to learn/use as Tina, but you can't argue with the price.

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:30:46 pm
content: Thanks guys. I just bought a used copy of Learning the Art of Electronics for $40 shipped. It's in very good condition according to the seller. I guess I'll be penciling in all the errata corrections as I go.I guess this (along with the 3rd edition of Art of Electronics) should be how I get started into electronics? Just read the book sequentially .. and do every lab sequentially? Ignore all other electronic books until I get through this entire thing? Maybe perhaps put off the synth projects until I'm done with this book? I have a lot of time free time as I don't work. Maybe after getting through the entirety of these two books I'll actually know something lol.

author: iainwhite
author_rank: Unknown
timestamp: February 23, 2017, 09:31:42 pm
content: I recommend the Third edition but I also picked up a 2nd hand copy of the Second edition on ABEbooks as well.If you decide to do the labs with real components, take a look atthis threadwhere a member has posted Excel spreadsheets of all the parts and where to buy them.There are also some comments in the thread about alternate parts to save money (particularly regarding the Linear Tech parts)Good luck!

author: ZeTeX
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:40:15 pm
content: I can recommend you allaboutcircuit. (https://www.allaboutcircuits.com/)in the /education section, you can learn quite a lot.Also there is a thread here somewhere about a lot of YouTube channels who teach electronics, check it out.

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:40:27 pm
content: NOTE: This message has been deleted by the forum moderator Simon for being against the forum rules and/or at the discretion of the moderator as being in the best interests of the forum community and the nature of the thread.If you believe this to be in error, please contact the moderator involved.An optional additional explanation is:

author: rstofer
author_rank: Super Contributor
timestamp: February 23, 2017, 09:42:30 pm
content: Quote from: JenniferG on February 23, 2017, 09:13:52 pmLTspice XVII is the latest version and it's brand new! I use it because it is free but TINA (TI version) has some neat features and it may also be free:http://www.ti.com/tool/tina-TIThey used to want money...I wouldn't spend any money for a simulator. First, LTspice works very well and second, simulation isn't hardware. It is possible to model assumed parasitics but you can never be absolutely certain that the model totally represents the hardware. Somehow, jamming signals in one end and watching scope wiggles on the other end is a lot more satisfying. And look at the range of hFEfor an ordinary transistor and you see where your amplifier gain can be all over the map. See page 2 here:http://web.mit.edu/6.101/www/reference/2N2222A.pdfThat is a lot of parts and we haven't even discussed your test equipment. Ultimately, you get nowhere without a scope. There is nothing that comes close to seeing the real life wiggles. And then there is the signal generator and the digital IO or logic analyzer, and so on... I going somewhere with this...Consider the Analog Discovery from Digilent along with the much cheaper box of analog widgets. This gadget, along with the BNC Adapter and 4 scope probes makes a dandy lab for just about anything at modest frequencies and voltages. One of the cool gadgets is the network analyzer where you can stuff a sweeping signal into a filter or an amplifier and get back the amplitude and phase angle versus frequency. Try that with a scope! This tool is ideal for learning and it is ultra portable. Doing Electronics at Starbucks!http://store.digilentinc.com/analog-discovery-2-pro-bundle/This setup will get you going and satisfy your needs for a very long time. I like mine a lot! But, yes, I have a bunch of other stuff as well.

author: Len
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:56:27 pm
content: Quote from: JenniferG on February 23, 2017, 09:44:01 pmAnd just plain stupid too. Looking in my youtube feed, I see three electronics videos by women, just today.

author: Len
author_rank: Frequent Contributor
timestamp: February 23, 2017, 09:59:18 pm
content: Quote from: JenniferG on February 23, 2017, 08:12:08 pmThat's cool. I've thought about doing a synth project but never got around to it. I hope you'll keep us updated on your progress!

author: IanB
author_rank: Super Contributor
timestamp: February 23, 2017, 10:04:08 pm
content: Quote from: JenniferG on February 23, 2017, 08:12:08 pmOne thing such circuits have in common with software is that seemingly complex things are made up of building blocks. Such a circuit full of transistors and stuff can be broken down into relatively fewer functional blocks each of which does a particular job. View a transistor as a line of code and a building block as a module or a class.With time and experience you will learn how to see the building blocks even if they are not highlighted on the circuit diagram.

author: iainwhite
author_rank: Unknown
timestamp: February 23, 2017, 10:05:48 pm
content: Quote from: JenniferG on February 23, 2017, 09:44:01 pmI hope you stick with the forum, Jennifer. The comment is not representative of the membership as a whole.

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 10:19:38 pm
content: Anyways, I appreciate the advice I've been given about the Art of Electronics book. I heard about this book before from the Muffwiggler forum, that it was particularly good. Ordered it along with the "Learning the Art of Electronics" book. I might end up buying all the components as well. I suppose I could use many of them or sell them off to someone else at a discount after I am done with them (as a set) -- assuming I don't blow any of them up!I hope you guys don't mind if I have a question from time to time as I do projects throughout the book.

author: EEVblog
author_rank: Unknown
timestamp: February 23, 2017, 10:19:44 pm
content: Quote from: iainwhite on February 23, 2017, 10:05:48 pmYes, sorry you got that remark Jenifer, it is certainly not representative of the forum. You won't get hassled here because of your gender I can assure you of that.I have no hesitation at all in banning anyone who thinks it would be fun to do that. lordvader88 has been given a few days to cool off and learn a lesson.

author: cvriv
author_rank: Frequent Contributor
timestamp: February 23, 2017, 10:26:16 pm
content: I've had at least one lady in each of my EE classes:) It's always a pleasure.

author: Stuartambient
author_rank: Regular Contributor
timestamp: February 23, 2017, 10:31:35 pm
content: I was just watching a new video today from Sparkfun. It is an arduino based synth kit. It actually sounds, at least from the video, pretty good. Check it out, it looks cool.

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 10:40:36 pm
content: Quote from: IanB on February 23, 2017, 10:04:08 pmThanks.I guess I'll learn all about these building blocks from the Art of Electronics books (including the labs one). I am very excited. I have always been so very intimidated by analog electronics and just confused the heck out of me. Glad I was recommended an approachable pair of books that can get me going in the right direction. Maybe after I am done with them, I can whip through schematics and understand and enjoy the design decisions.It's really nice to know a forum like this exists. I've been watching eevblog videos on youtube for a while and didn't know about this forum until recently. I really love his excitement in the videos and how well he explains things. (Love his stereotypical large crocodile dundee knife when opening mailbag packages .. oh my .. ROFL.. excellent! -- He's so approachable and like the Steve Irwin of Electronics.) Glad to have his videos, other youtube vids, this forum and google in general as I go through this book.Electronics have always been something I've wanted to tackle since I was a child and interested in computers. Always dabbled in them, but super basic stuff . [My first computer was a commodore 64, then an Amiga 1000, followed by Pinecom XT Clone lol -- didn't know about registers, binary, memory addressing and machine language programming until I was a freshmen in college believe it or not, as I wasn't brought up in the most encouraging household; e.g. father didn't even go to high school and disliked computers.]

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 23, 2017, 11:05:49 pm
content: Quote from: Stuartambient on February 23, 2017, 10:31:35 pmThanksI have a couple of old Commodore 64 SID chips laying around here (along with a fully functioning C64 I use from time to time -- have a thing for my first puter I guess lol). Would be cool to hook up the SID to an arduino and have the arduino receive MIDI data/notes and play them on the SID. Have some pots for cut offs etc. Also have CV/GATE control and perhaps integrate into a modular synthThis seems more apporachable to me since most of it is digital electronics vs. building my own analog VCO with a bunch of TL071 TL072 LM31700 op amp chips along with loads of resistors and capsWOndering how I'd sync the clocks of the SID to the arduino. I guess I'd have to build a custom arduino with a slower oscillating crystal? One that matches the SID?

author: rstofer
author_rank: Super Contributor
timestamp: February 24, 2017, 12:30:22 am
content: Quote from: JenniferG on February 23, 2017, 11:05:49 pmYou can get the SID clock from anywhere. The bigger problem is the read and write cycle timing. Yes, the cycles need to be synch'd with the clock and that will need to have some relationship to the Arduino but I didn't find an example with a quick Google search. I did find some attempts to emulate the SID with an Arduino. Perhaps a more exhaustive search.What I did run across was an attempt to replicate the SID chip in an FPGA. Now that's just code. I don't know anything about Synths but when the topic drifts toward building things in an FPGA it gets me to thinking...OR... Why not just build the thing based on a real 6502? At least so far as interfacing with the SID. You can send MIDI commands to the 6502 and it can deal with the SID. An Arduino could send the commands... Alas, I know nothing about Synths so this may not be workable. The 6502 never was a powerhouse.http://www.jameco.com/z/6502-Major-Brands-MPU-R6500-CISC-8-Bit-1MHz-40-Pin-CDIP_43191.htmlMany years ago I used these chips to build hard disk interfaces for the Apple II. I used a cross-assembler running on my Altair, I believe. Somewhere around '80 or so...OR... I might consider a CPLD (Complex Programmable Logic Device - like a mini-FPGA) to get in the middle between the Arduino and the SID. The CPLD would take parallel input from the Arduino and write it to the SID with proper timing.

author: MarvinTheMartian
author_rank: Frequent Contributor
timestamp: February 24, 2017, 12:43:23 am
content: Hi Jennifer, welcome to the forum!I find this forum is very friendly and helpful to 'newbies' (whether male or female) and very informative as well (along with Dave's videos).I too have a long time interest in electronics but have not had the time to really get into it, sadly.But now that I've retired I can dedicate some more time (subject to constraints looking after my wife who has disabilities).Hang in there - you will find it very rewarding.

author: pitagoras
author_rank: Regular Contributor
timestamp: February 24, 2017, 01:33:04 am
content: Quote from: JenniferG on February 23, 2017, 08:12:08 pmCool. Me too. I paste my Evernote page so farI hope you find useful stuff...Dave Smith Instruments Prophet 6Analyzed herehttp://polysynth.tumblr.com/post/134667237805/a-quick-tour-of-the-prophet-6-voice-cardhttp://electronics.stackexchange.com/questions/34970/design-for-an-analogue-oscillator-that-doesnt-drift-in-frequencyMicromoog service manualhttp://www.cyborgstudio.com/synthmp3s/moog/micromoog/manual/micromoogmultimoogservicemanual.pdfBuilders/Kits/DIYhttp://musicfromouterspace.com/https://docs.google.com/file/d/0B3wD73e_RyWdbFlUbEpqeExRa0U/editHybrid, polyphonic, discontinued:http://mutable-instruments.net/ambikaKIT MOOOG!!!!!https://www.residentadvisor.net/reviews/16773VCOhttp://www.birthofasynth.com/Thomas_Henry/Pages/VCO-1.htmlhttp://www.allaboutcircuits.com/projects/diy-synth-series-vco/https://www.gearslutz.com/board/electronic-music-instruments-electronic-music-production/1111463-how-do-continuously-variable-oscillators-work.htmlCIRCUITShttp://www.univertron.com/SAS/manuals/RSF/Kobol%20Expander%20Schematics/continuously variable waveformContinuously variable waveshape:See Moog sub 37https://www.gearslutz.com/board/electronic-music-instruments-electronic-music-production/800682-best-favorite-diy-analog-synth-kits.htmlElectronic music & microprocessors bookhttps://github.com/rabidaudio/synthesizer/blob/master/reference/Musical-Applications-of-Microprocessors-2ed-Chamberlin-H-1987.pdfSee also this: Moog 32 semi modularPLL Based enhttp://www.birthofasynth.com/Thomas_Henry/Pages/X-4046.htmlseems appreciated:http://randomsource.net/modulesSomeone did some modular:http://people.carleton.edu/~jellinge/mysynth.html

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 01:40:40 am
content: Thanks for the linksI just bought a Moog Mother 32 recently. Enjoying itThat's why I wanted to build a VCO-555 first, because my Mother 32 needs another voiceIt's actually quite cheap to make. One LM13700, 555 chip and a few TL071 TL072 type op amps. I think the most expensive parts are the pots, knobs & jacks (ouch).Here's Thomas Henry's introduction of the VCO-55: discussion, schematics & BOM.http://electro-music.com/forum/topic-54623.html

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 01:56:37 am
content: An example of my current limited electronics knowledge. A midi controller for Roland TR-808 & TB-303 VST plugin clones. Top left knobs controlled the bass and the rest are the drums (below). Top right was tempo. LCD panel showed you which parameters you were adjusting when you turned a knob along with its value.Used an arduino micro for all these pots by using the lil 4051 multiplexer chips. Used 3 data pins on the arduino to set the 3 bit address to select which pin to read from. It just scanned everything over and over in a loop -- very rapidly -- and observed any changes. Set the variable with new value, sent the midi control message and updated the display.Used chipboard and cardboard for this prototype lol.Here's the code. Some of it pretty sloppy I'm sure.. just threw it together.Code:#include <LiquidCrystal.h>//#define DEBUG /* uncomment this line to run in serial monitor debug mode */#define NUM_KNOBS 14#define NUM_SWITCHES 1#define NUM_TOGGLES 1#define KNOBS_CHANNEL 0#define SWITCHES_CHANNEL 1#define TOGGLES_CHANNEL 2LiquidCrystal lcd(12, 11, 5, 4, 3, 2);int switches ;int toggles ; //pseudo toggles w/ momentary switchesint toggles_low_flag;int mux_select_pins[] = {7, 8, 9};int knobValue;int oldKnobValue;int prevOldKnobValue;int toggle = 1;String lastKnobTitle = "";String knobTitles = {"TEMPO", "BASS VOL", "DRUMS VOL","ACCENT", "DECAY", "CUT OFF FREQ", "ENV MOD", "RESONANCE","BASS LVL", "BASS TUNE", "BASS DECAY", "SNARE LVL", "SNARE TUNE", "SNARE SNAP"};void setup () {memset(switches, 0, sizeof(switches));memset(toggles, 0, sizeof(toggles));memset(toggles_low_flag, 1, sizeof(toggles_low_flag));#ifdef DEBUGSerial.begin(38400); // serial monitor debugging instead of midi#elseSerial.begin (31250); // set to midi baud rate#endifpinMode(mux_select_pins, OUTPUT);pinMode(mux_select_pins, OUTPUT);pinMode(mux_select_pins, OUTPUT);pinMode(4, INPUT);lcd.begin(16, 2);lcd.setCursor(0,0);lcd.print("TB-303 & TR-808 ");init_values();}void init_values() {for (int i=0; i < NUM_KNOBS; i++) {int analog_input_pin;int analog_channel = i % 8;int x = i / 8;if (x == 0) {analog_input_pin = A0;} else if (x == 1) {analog_input_pin = A1;} else if (x == 2) {analog_input_pin = A2;} else {analog_input_pin = A3;}delay(1);knobValue = readMux(analog_input_pin, analog_channel);// write to midi channelmidi_ctrl_write(KNOBS_CHANNEL, i + 1, knobValue);}}void loop () {// handle knob tweaksfor (int i = 0; i < NUM_KNOBS; i++) {int analog_input_pin;int analog_channel = i % 8;int x = i / 8;if (x == 0) {analog_input_pin = A0;} else if (x == 1) {analog_input_pin = A1;} else if (x == 2) {analog_input_pin = A2;} else {analog_input_pin = A3;}knobValue = readMux(analog_input_pin, analog_channel);if (knobValue != oldKnobValue) {if (knobValue != prevOldKnobValue) {// write lcd infoif (lastKnobTitle != knobTitles) {lastKnobTitle = knobTitles;lcd.setCursor(0,1);lcd.print(" ");lcd.setCursor(0,1);lcd.print(knobTitles);}if (knobValue < 10) {lcd.setCursor(13, 1);lcd.print(" ");lcd.setCursor(15, 1);} else if (knobValue < 100) {lcd.setCursor(13, 1);lcd.print(" ");lcd.setCursor(14, 1);} else {lcd.setCursor(13, 1);}lcd.print(knobValue);// write to midi channelmidi_ctrl_write(KNOBS_CHANNEL, i + 1, knobValue);prevOldKnobValue = oldKnobValue;oldKnobValue = knobValue;}}}/*// handle switches & buttons (momentary switches)if (digitalRead(4) == HIGH) {if (switches == 0) {midi_ctrl_write(100, 127);switches = 1;}} else {if (switches == 1) {midi_ctrl_write(100, 0);switches = 0;}}*//*// handle toggles (momentary switches emulating toggles)if (digitalRead(4) == HIGH){if (toggles_low_flag == 1) {if (toggles == 0) {midi_ctrl_write(TOGGLES_CHANNEL, 100, 127);toggles = 1;} else {midi_ctrl_write(TOGGLES_CHANNEL, 100, 0);toggles = 0;}toggles_low_flag = 0;}} else {// LOWtoggles_low_flag = 1;}*/delay(10);}void midi_msg_write(int statusbyte, int data) {midi_msg_write(statusbyte, data, -1);}void midi_msg_write(int statusbyte, int data, int data2) {#ifdef DEBUGSerial.print(statusbyte);Serial.print(" ");Serial.print(data);if (data2 != -1) {Serial.print(" ");Serial.print(data2);}Serial.println();#elseSerial.write(statusbyte);Serial.write(data);if (data2 != -1) {Serial.write(data2);}#endif}void midi_ctrl_write(int channel, int controller_num, int controller_value) {int statusbyte = 0XB0 + channel;midi_msg_write(statusbyte, controller_num, controller_value);}int readMux(int common_analog_pin, int mux_channel) {// select the mux channel for the knob value we want to readdigitalWrite(mux_select_pins, bitRead(mux_channel, 0));digitalWrite(mux_select_pins, bitRead(mux_channel, 1));digitalWrite(mux_select_pins, bitRead(mux_channel, 2));// read knob value corresponding to the mux channel we just selectedreturn map (analogRead(common_analog_pin), 0, 1023, 127, 0) - 1;}

author: tpowell1830
author_rank: Frequent Contributor
timestamp: February 24, 2017, 03:49:22 am
content: Quote from: JenniferG on February 23, 2017, 11:05:49 pmGlad to see enthusiasm Jennifer. Check out Jeri Ellsworth. She has started a company called castAR now and hasn't posted in a long time.https://www.youtube.com/user/jeriellsworth/videosShe completely built a C64 with FPGA.

author: jh15
author_rank: Frequent Contributor
timestamp: February 24, 2017, 06:05:36 am
content: Wish Jeri was more active, miss her.Fran Blanch has become more active lately on her Youtube channel, I reached out to keep her going on her recent begathon.Result of her recent fantastic pipe organ "teardown" video makes it worth my support. Used to record and stand in the things climbing around with the tons of audio recording equipment.

author: Don Hills
author_rank: Regular Contributor
timestamp: February 24, 2017, 08:58:53 am
content: Quote from: JenniferG on February 23, 2017, 10:19:38 pmI just had to go look that up. I learn a little every day...

author: brucehoult
author_rank: Super Contributor
timestamp: February 24, 2017, 09:02:43 am
content: Cool project and generally nicer code than usually seen :-)I'd have used an array not a switch to choose analog_input_pin (as for mux_select_pins).oldKnobValue and prevOldKnobValue are pretty funky. A bit of hysteresis to allow for imprecise A/D conversion?I'm confused why you subtract 1 from the result of the map() in readMux. Is -1 a useful value? And anyway the map() could have done that :-)Not criticising, just curious and I probably over optimise stuff ... I've certainly written plenty of "when it works it's Good Enough" code, especially for microcontrollers!

author: technogeeky
author_rank: Frequent Contributor
timestamp: February 24, 2017, 01:24:24 pm
content: Quote from: cvriv on February 23, 2017, 08:26:42 pmI want to be the first to say...seconded.

author: bibz
author_rank: Contributor
timestamp: February 24, 2017, 01:26:07 pm
content: I too am making my own modular and started with a Thomas Henry design. I have made a VCO-1 VCF-1 and VCA-1. It sounds amazing and was a lot of fun so commited to a 5u setup 600mm wide and 2 rows tall. I plan on updating the vco-1 with a vco555, and adding a whole slew of Yusynth projects.http://yusynth.net/Modular/index_en.htmlYves Usson did the design and stuff for the Arturia synths. I picked up a minibrute to interface with my modular, CV with an extra ADSR and LFO. It's awesome to see other diy'ers out and about (outside of the Muffwiggler and electro-music forums).Thanks heaps to pitagoras aswell! I got quite a bit from those links that I hadn't seen before. Especially like the Prophet 6 breakdown.I know little about the modern day microprocessor electronics, coming from a more guitar oriented background. Cutting my teeth on a silverface fender amp and redoing its power section has prepared me pretty well for not missing the small stuff/touching the wrong thing! I can't help but love the old way, turret boards and point to point artwork. But in the quest for DIY synthesis I'm keen to find out why X sounds different to Y. And I want to breadboard it up myself to see and hear the difference.For instance I'm making two Yusynth VCO's at the moment. And like Jennifer my first oscillator was just there and worked. Now I can point out the parts and whys of the design. Mostly

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 01:36:34 pm
content: Quote from: brucehoult on February 24, 2017, 09:02:43 amRegarding the prevOldKnobValue, actually the circuit didn't work right until I added that. Kind of proud of adding that actually; added it after I debugged a problem I was having. The potentiometer value jumps around at one given setting at times, so it constantly tells the scanner it's changing value hundreds of times per second, even though the user isn't turning it.Again for the rest, I just threw it together, didn't spend time optimizing nor did I finish the projectI started then stopped after I decided I didn't want to use VST for TB-303 and TB-808. I wanted the physical hardware

author: brucehoult
author_rank: Super Contributor
timestamp: February 24, 2017, 01:53:18 pm
content: Yes, as I suspected :-)I wonder if this would work as well?Code:newValue = readMux(analog_input_pin, analog_channel);if (abs(newValue - knobValue) > 1) { knobValue = newValue; ... }

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 02:42:20 pm
content: Quote from: brucehoult on February 24, 2017, 01:53:18 pmI think I did something similar at first -- actually, I think the exact code you just shared now. However, it lowers the resolution of the changes. e.g. If the user is slowly turning the knob constantly left over a performance, with my code as is, it is changing in increments of one, smoothly. With the code you suggested, it would only change in increments of two and be rougher -- also, when you get to say a level of 1 you couldn't turn it down to zero.

author: FrankBuss
author_rank: Unknown
timestamp: February 24, 2017, 03:08:01 pm
content: Quote from: JenniferG on February 23, 2017, 11:05:49 pmI know someone who has built a SID player with a real SID. He used a big microcontroller, an AT91SAM7:The simple solution for the clock was an 1 MHz external oscillator, which I sent him and helped him a bit with building this thing (seehttp://www.mikrocontroller.net/topic/197960). He implemented a full C64 emulator in order to play SID files.Of course, this might be too much for a poor Arduino, but it should be possible to create a 1 MHz signal with the PWM output of the Arduino and to program a simple MIDI synthesizer. Synchronization could be a problem with a standard 16 MHz Arduino, you might need inline assembler to set the data and address bits and from a timer interrupts, to met the timing requirements (setup and hold time etc.). Unfortunately on the Arduino you can't specify interrupt priority, like with the STM32 microcontrollers, so you might have to disable the millisecond interrupt, or try to do the synchronization inside this interrupt and call the original Arduino interrupt after your function, and poll the rest, like the serial port for the MIDI input.With a full C64 you can build interesting hardware for it as well. This is one of my projects:http://www.frank-buss.de/kerberos/index.html

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 03:34:02 pm
content: Very cool!I've read about cynthcart and wanted it. Nice to see your custom MIDI interfaceI have easyflash, jiffydos and sd card reader on my c64 nowHere is a photo of my Commodore 64 I just snapped. I am particularly proud of the little 1541 sticker I made for the built in SD card reader[Another example of myvery limitedelectronics experience lol.. pop in a board, find a way to mount it.. connect it up and go. After all these years, I am decent at soldering and de-soldering at least.]Nice to be able to store thousands of c64 programs on one little chip. Who would of thought (back in the day)?! I remember my big tub of "single-sided" 5.25" floppy disks.. punched to be able to use the back side of the disk as well

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 03:41:38 pm
content: Quote from: raspberrypi on February 24, 2017, 03:40:05 pmHello. Don't know what to say. I guess I wish there was a Welcome Wagon subforum here. Other forums have it. I guess I apologize for trying to do a friendly introduction.I'd love it if the moderator would just delete all references to gender from this thread and any negativity I or others have caused. I feel awkward. Never had this issue before on other forums. Not even in the muffwiggler DIY section.Or better yet, it might be more convenient to just delete this entire thread, please.

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 04:08:52 pm
content: Quote from: JenniferG on February 24, 2017, 03:41:38 pmThread cleaned up as much as possible. Please don't take offence anyone who's post ws deleted, I've tried to leave just the technical stuff.

author: rstofer
author_rank: Super Contributor
timestamp: February 24, 2017, 05:34:18 pm
content: Quote from: JenniferG on February 23, 2017, 09:13:52 pmOn the subject of number crunching, I want to bring up wxMaxima as a Computer Algebra System (CAS). This program is superb! If you do a little search, you will find one of Simon's threads with some examples of solving his homework.The learning curve seems a bit steep but there are a couple of books that break it down pretty well:https://wxmaximafor.wordpress.com/Of course you can find a ton of help via Google but the User Manual isn't one of the easiest things to read. I tend to search for more specific topics and see what pops up.I have only been playing with the program for a couple of weeks but it is now my #1 tool for verifying my grandson's Calculus I homework. Well, that and desmos.com (graphing) and symbolab.com (just about everything).When you get to the lab experiment for charging a capacitor, wxMaxima rocks. For giggles, I decided to code this up and get a 2D plot.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 05:58:58 pm
content: What does the SPICE program have to do with the title of this thread?The subject of this thread is only a first and very good presentation.Jennifer should open a new specific topic for each technical question she wants to ask.

author: IanB
author_rank: Super Contributor
timestamp: February 24, 2017, 06:05:20 pm
content: Quote from: oldway on February 24, 2017, 05:58:58 pmIt's a discussion with questions about how and where to get started. Seems quite relevant to me. What's the problem?

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 06:11:41 pm
content: The problem is that somebody who looks for informations about this SPICE program will not find them because they are not related to the tittle of the thread.

author: rstofer
author_rank: Super Contributor
timestamp: February 24, 2017, 06:15:24 pm
content: I'm pretty sure everything will show up when using Search.I just searched for wxMaxima and came up with a bunch of hits including the one of mine above. Lots of hits in Simon's homework thread.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 06:23:40 pm
content: You know very well than most of the people don't use the "Search" function, they simply look at the tittle of the threads...That's what I do....I look at the tittle and I only read the posts if the tittle interest me.Its is a forum, not a chat !The technical informations must be easily found by everyone....simply reading the tittle of the thread.

author: brucehoult
author_rank: Super Contributor
timestamp: February 24, 2017, 06:29:52 pm
content: Quote from: JenniferG on February 24, 2017, 02:42:20 pmYes, quite right. With your solution noise might get you there early sometimes, but you'll at least get there. Hmmm ... thinking ...

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 08:37:27 pm
content: Quote from: oldway on February 24, 2017, 06:23:40 pmIf that is the case as the thread fast dissapearsd on the pile it still won't be of any use despite the title.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 09:08:04 pm
content: 5) This is an electronics forum, so try to stay on-topic. We understand that threads drift off-topic, but try not to start deliberately and grossly off-topic stuff.What is the definition of "off-topic" ?The tittle of the thread seems to be the topic ....or not ?

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 09:21:24 pm
content: the title of the thread was pretty much "hello world", theres not much more to talk about on that. If we applied rules as you suggest there would be no forum and we'd spend all of our time having to move/rename topics and edit the entire forum. I'm happy to see a first topic slip but would expect future topics to stay roughly on topic. You are being a bit pedantic.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 09:31:02 pm
content: Quote from: Simon on February 24, 2017, 09:21:24 pmI only try to understand the rules of the forum....I see most of the topics with a clear tittle and answers "on-topic"....I am surprised to see a potpourri subject where we talk about different subjects without any relationship between them....Is that "pedantic" ?

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 09:37:44 pm
content: This is a first topic by a new user with no more initial intent than anouncing themselves and expressing their interests. So some discussion has ensued, the actual topic title does not warrant any response per se if we want to do it by the book that much. As it is a first topic by a nerw user I don't care what it ends up talking about. I am sure the next time the new user creates a topic it will have a well defined purpose and the responses will be pertinent. Some forums do indeed have a "new member come and anouce yourself section" which is meant as a throw away section for users to make a first post in if they so wish to test the forum out. We don't have such a section and it's no surprise the begginers section will have such a topic as it's the most pertinent section for that.The issue of staying on topic usually relates to things that can be a bit more controversial or for those users that can turn any topic in a political/religious you name it spin off to troll and argue in. This forum does also pride itself in not being over moderated and strict. Most of the rules are there for people who want to sail as close to the wind as they can and beyond and them use the lack of rules as an excuse for disruptive behaviour on the forum.

author: FrankBuss
author_rank: Unknown
timestamp: February 24, 2017, 09:46:25 pm
content: Quote from: JenniferG on February 24, 2017, 03:34:02 pmNice, I like the sticker. Yep, who would have thought back in the days that you could integrate a 1541 floppy drive, and thousands of disks, into the C64?The EasyFlash 3 is a good device (my Kerberos cartridge emulates EasyFlash 1, too, so you can play Prince of Persia from CSDb with it, a very good C64 port). With the USB port of the EasyFlash 3 you can upload programs direct to the C64, good for cross compiling on a PC and fast testing on the real machine. That's very useful if you want to test some DIY hardware attached to it, or special SID features which the emulators can't do. It's crazy what you can do with the SID. Do you know this demo? Only recently VICE has been updated to play it correctly.It sounds awesome, like an Amiga. But some of the magic of the simple SID sounds is lost with these new digi tricks.Have fun with your SID-Arduino-MIDI project. If you have a good keyboard with knobs and wheels, maybe map the SID filters to the knobs and the wheel to the pitch, implement some C64 style effects like arpeggio, and then play some musicOr write your own tracker on the Arduino and then write some music for it or port some of the old musics. One of my all time favorites is the Tetris music (no, not the annoying Gameboy music)

author: MrAl
author_rank: Super Contributor
timestamp: February 24, 2017, 09:49:15 pm
content: Quote from: JenniferG on February 24, 2017, 03:41:38 pmHi again Jen,I think maybe you just need to grow a little thicker skin. As i tried to explain before, there are nasty people on the web who will always find a way to cause trouble and believe me it is not anyway limited to gender. Anything they can find that looks even a little questionable to THEM (not necessarily to anyone else) may get a nasty comment.But overall i find many more nice people who like to help others regardless of gender or where they come from.As to your project, if you have never built anything electronic yet maybe start with something simpler like an op amp circuit or something and dig into the theory and measurements and you'll get going pretty fast.You also have to check more than the last post that was posted in a forum because there could be 10 posts after yours that you will want to read that may contain much useful information.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 09:49:37 pm
content: Quote from: Simon on February 24, 2017, 09:37:44 pmThank you for all these explanations but let me tell you that after all the time I spent on this forum to help others, I did not appreciate being the victim of personal attack on your part. .... I do not ask for any thanks for my more than 1000 posts, but there is a minimum of gratitude that must be respected, even when you are a moderator.

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 09:54:53 pm
content: Quote from: oldway on February 24, 2017, 09:49:37 pmI have not attacked you. I have simply explained how we try to run the forum to keep it reasonably orderly but also friendly. Maybe english is not your first language. As a moderator I don't see myself above anyone, I am simply entrusted to step in if things get out of hand and take the abuse I sometimes get for trying to preserve the forum for the MAJORITY despite a minority that sometimes try to disrupt things because they think it's fun. You should try being a moderator sometime.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 10:01:13 pm
content: QuoteIs this not a personal attack ? English is not my motherlinguage, but if I translate it in French, that's for sure an unfair and inacceptable personal attack.

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 10:03:39 pm
content: Well in english it's not an attack, it's an expression of an opinion, and the "a bit" tones down the meaning of the word that follows, not that I'm an expert of english.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 10:17:54 pm
content: In French, to be pedantic is to treat others as if they were inferior, to lack them with respect and consideration.It's has been a shock to hear this talk while I have been volunteering for almost 10 years to help others, mainly poor and disadvantaged people.I am also participating for 4 years as volunteer of the repair cafes, repairing free of charge.all that people bring to us.For an instant, I thought to quit this forum definitively.

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 10:22:15 pm
content: Quote from: oldway on February 24, 2017, 10:17:54 pmWell to be honest I have no idea what you do outside of this forum and what you do outside of this forum is totally irrelevant to this forum. Obviously it's very nice that you do these things and I also do quite an amount of voluntary work but I don't expect to get recognition for it on this forum.Not that I'm an expert on language but in the past I have used the word pedantic as a compliment particularly when talking about an assembly house. Working for a company where documentation is often quite loose and ill-defined it is a pleasure sometimes a deal with a supplier that is pedantic about their paperwork as it forces my employer to allow me to produce precise documentation.Words often have different meanings in different languages even though they are a direct translation. There will be an amount of culture behind their use.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 10:35:24 pm
content: If I understood correctly, to be pedantic would mean something like to be demanding.....something quite different than the french translation "être pédant" (Qui fait prétentieusement étalage de son savoir ; cuistre)

author: Simon
author_rank: Unknown
timestamp: February 24, 2017, 10:38:27 pm
content: Well in English to be pedantic is to want something to be just so and so. If you are a pedantic boss then yes you would be demanding because you would be expecting other people to carry out things just the way you want them doing whether or not it is strictly necessary or productive. However it can also be applied in many other ways such as the way I used it where I was meaning that you were expecting the rules to be applied in such a rigid way that it was going to be almost pointless for the functioning of the forum if that makes sense. Or to put it another way pedantic can be used in replacement of strict. Your interpretation of the rules were very strict which in one word can be replaced by pedantic.

author: oldway
author_rank: Super Contributor
timestamp: February 24, 2017, 10:45:49 pm
content: Ok, understood.....many thanks for your patience....

author: EEVblog
author_rank: Unknown
timestamp: February 24, 2017, 11:15:47 pm
content: Quote from: oldway on February 24, 2017, 09:08:04 pmJenifier started the thread. If she wants to go on and discuss her technical stuff in here then she can.But yes, it's better if people start separate threads for each new question, as it separates the discussions, but you don't have to harp on about it, she is new here.Now a third of this thread is polluted by talk about this

author: ZeTeX
author_rank: Frequent Contributor
timestamp: February 24, 2017, 11:22:37 pm
content: If you want a fun and useful project maybe build a good current limited power supply, its a very useful thing and you learn a lot about electronics in general because generally when designing a PSU a lot of random knowledge about electronics is combined together, and you can make it 99% pure analog..*I'm not talking about LM317 based PSU but more like from scratch with not IC's other then op amps.

author: The Soulman
author_rank: Super Contributor
timestamp: February 24, 2017, 11:39:53 pm
content: Quote from: ZeTeX on February 24, 2017, 11:22:37 pmIn the original post from the original poster:Quote from: JenniferG on February 23, 2017, 08:12:08 pm

author: JenniferG
author_rank: Frequent Contributor
timestamp: February 24, 2017, 11:47:34 pm
content: Thanks everyone for all the help. I got what I want out of this thread. I introduced myself here (because there wasn't an Introductions sub-forum and I am a "beginner"), I gave info on my background along my current capabilities, and I did post with intent on perhaps getting some suggestions how I should approach learning electronics.I've gotten excellent advice (thank you) and I've purchased the Art of Electronics (along with the labs book) and I'll learn about electronics sequentially using those books. I doubt I'll do much of any projects until I get through with those books.I enjoyed the friendly discussion back and forth as a typical introduction thread has. I suggest this forum create an area for introductions, so this isn't a problem in the future. Allowing free-for-all discussions within the introduction area, would be prudent.Sorry to have annoyed anyone looking for specific "topic related" information -- despite me personally feeling this thread did not go off topic, because what I said and help I asked for is typical of an introduction thread. I feel it DID go off topic when gender related comments were introduced and perpetuated.Again thank you for all that have helped me. I appreciate all the helpful comments and friendly welcoming replies.I'd appreciate it if a moderator wouldlockthis thread now. This thread has fulfilled its usefulness.

author: Brumby
author_rank: Unknown
timestamp: February 25, 2017, 12:11:44 am
content: I am glad you have found your way to the EEVblog forum - and that you have found some very useful contributions on this first encounter.The technical information available from members here is, indeed, quite varied - from people who have spent a few weeks blowing things up on their own hobby workbench to people who have spent 20 years ensuring things DON'T blow up in an industrial setting. There are members here from all over the world and that is going to encompass a wide range of personalities, experience and opinions.Hang in there.