Brand new to this with no real background, a few Q's...

Started by ledauphin, May 24, 2010, 06:23:44 PM

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ledauphin

Hello, I joined this forum recently in hopes of sort of expanding my knowledge in the realm of DIY pedal-making, and am currently attempting to build a relatively simple fuzz. I have a few questions that I wasn't sure where to look in regards to, so maybe someone can help me out and scrub me of the NeWb status.

1.) Is there any particular aspects to circuitry, or electrical engineering perhaps, that make the process easier, or at least easier to understand? i.e. literature or links in the forum
2.) When getting resistors for the item, I noticed that only certain degrees of resistance were available in different wattage, 330kOhm in 1/8 and 1/4 but perhaps something else I required for the schematic in 1/2" or larger, etc. How does this come into play, and does continuity play a large role in the build?

I'm sure more will arise as I go along, just wanted to ask those two before proceeding and having a pile of useless soldered wire. Thanks ahead for any input!

petemoore

  Getting how Ac and Dc relate is a big one.
  AC is frequency of some sort. This means you can separate [to some degree or other] certain frequencies, change the amplitude of X band etc.
  DC has no AC in it [if only...], the steady pressure potential is used to 'make' [it supplies voltage/current to the amplifier] AC 'again' at the output [larger potentials or what is often miscalled' 'louder'.
  I'm already discussing a gain stage for reference...a FF is just a bit more complicated, but a simple booster makes it more intense.
  More than that, whipping up a simple 1 transistor boost on..anything..perfboard, breadboard...then measure the voltages, the say tweek the emitter resistor and notice how that changes the bias voltage ont he collector.
  A working will have:
  DC blocking capacitors at the 'entrance and exit' points [for signal in/out].
  Resistors, these sometimes need to be closer than 'in the ballpark' [+or- 10% of shown value], measureing each one before installing is a good idea.
  Capacitors, polarized types are polarized, the - needs always to be at a more - potential than the other lead, most polarized caps are marked.
  Power supply, the schematic needs to be chosen for the transistor type, PNP Positive ground assignment, or NPN transistors in negative ground circtuit, anything with a polarized nature needs to follow the polarization of the circuit.
  Nodes, count the connections each node makes, make exactly that number of connections there...noting polarity before soldering.
  Ground, all ground markings are common = connected.
  A circuit board which has everything the schematic shows, represented in physical form.
 
Convention creates following, following creates convention.

stringsthings

#2
Quote from: ledauphin on May 24, 2010, 06:23:44 PM

1.) Is there any particular aspects to circuitry, or electrical engineering perhaps, that make the process easier, or at least easier to understand? i.e. literature or links in the forum
2.) When getting resistors for the item, I noticed that only certain degrees of resistance were available in different wattage, 330kOhm in 1/8 and 1/4 but perhaps something else I required for the schematic in 1/2" or larger, etc. How does this come into play, and does continuity play a large role in the build?



welcome to the world of DIY ! ....  ;D

1) knowing how to read a schematic is a really good idea, IMO ....

2) resistors have a wattage rating .... too much power and they get hot .... fortunately, most guitar-based DIY pedals only require 1/4 watt resistors .... if you're building higher voltage/current circuits, then the higher wattage resistors become necessary .... ( they're also more expensive ) ....

.... i'm not really sure what you mean by continuity ... ???

Pablo1234

Signal conditioning, Filtering passive and active, DC, AC, and Basic switching logic are all important to this. I recommend getting a few books from school libraries or look at some course books for -
1 - DC theory, this will give you a good introduction to Resistance, Voltage, Current, Wattage, transient responce and basic component introduction. Like the diode and its applications.
2 - AC theory, this will give you an introduction to impedance, reactance, rectification and basic filtering.
3 - Filtering is a Field unto itself, its used to do complex math functions on evolving signals. ie.. Equalization, integration, transient suppression and the like. The best book I have ever read on this subject is Active Filtering Cookbook. I have probably read it 20 times and I refer to it to this day for allot of circuit design. Heavy in math but you need to know math to really understand this stuff.
4 - Signal conditioning is another great focus on circuit design. I have a book dedicated to this topic but can't remember the name. But its a great Field to comprehend as it will give you insight on input and output impedance, transient suppression or excitation and your various signal sources (think Pickup) and basic circuits to manipulate them.
5 - Basic Switching logic is also very hand to really understand. From switch configurations to programable switching systems its allot more complicated than it sounds.

I also suggest microprocessor programing, if you have no experience with this kind of thing Parallax has a micro called the basic stamp and a whole lot of documentation and tutorials for free to download. Its a plug and program system that is allot more powerfull then you may imagine and has so many applications its not funny.

Welcome to the world of electronics, good luck and remember you will never stop having something to learn in this Field.

stringsthings

Quote from: Pablo1234 on May 26, 2010, 06:16:25 PM

3 - Filtering is a Field unto itself, its used to do complex math functions on evolving signals. ie.. Equalization, integration, transient suppression and the like.....

.... Its a plug and program system that is allot more powerfull then you may imagine and has so many applications its not funny.....


O.K. Pablo .... I think we'll just filter through your advice ..... BTW, read any good spelling books lately?