thanks to you I have found my first few capacitors. how about the size. when it says it should be Film capacitor, 7.2 x 2.5mm.
I guess this is the size for perfect match with pcb, but can i get away with smaller or larger size i guess it depends on the lengt of the component pins?
You'll be snipping off the excess length of the component pins. You want to find out the pin-spacing width.
So long as there's room and you're not going to short them out, pins can be bent and capacitors laid on their sides — so yes, smaller and sometimes larger physical packages can work — just don't box yourself into a corner: "
oh this'll fit...[solders in huge cap]
... oh dang, now I need to solder the pots and that monster cap is in the way..." Or "
it fit when I soldered it in, but the lid won't go on the enclosure 'cause the cap's too tall."
I'll try not to repeat what's already been posted, but some things bear repeating and others need clarification.
DO build something small to begin with as less parts means easier Trouble-Shooting. When opening your trouble-shooting threads (don't post in someone elses!), include clear photos that show the whole board (BOTH sides) and all its connections, close-ups of any suspected specific trouble-spots. The more you help those you seek to help you, the more likely the helpers are inclined to do so and the faster your build will be up and running properly.
Learn the parlance and common conventions.
It's NOT transist
er, it's
transistor
It's NOT resist
er, like someone who resists arrest, but
resistor
Capacitor, or cap, may be one of many kinds: ceramic, box-film, electrolytic, tantalum and sometimes mylar chiclets or monolythics. Check the lead spacing of your PCB before ordering. Most box-film will be 5mm while electrolytics are 2mm while ceramic, mylar and monolythic caps can vary but leads are easily bent in or out to suit your needs.
*Caps should be rated for about double or more of what you're running for juice in your pedal (including charge-pumps that bump things to 18v or 24v):
Power —> Cap-rating
9v —> use 18v caps
12v —> 25v caps
18v —> 35v caps
24v —> 50v caps
So don't order 600v caps for a pedal build, just 'cause they have the µF you need and are on sale.
Again, learn common conventions such as pin-numbering on toggles and footswitches — helps when troubleshooting if everyone is on the same page.
Know that
there is no one-stop shop,
so besides Tayda there's :
Mouser,
Digikey,
Stompbox Parts,
Cabintech for ICs,
Small Bear/SynthCube,
Love My Switches,
Amplified Parts
— depending on where you are in the world (ok, Scandinavia) you may have to hit up other resources such as MusikDing or ukelectronique.de, or even further afield such as DIYguitarpedals.com.au.
Hunt the forums for info on who's reputable or disreputable — Banzai, Ebay sellers, etc.
Resistors: Some builds may require 1/8w, but you can probably stand 1/4w on end to fit; vice versa — some builders only buy 1/8w to streamline their inventories.
Pots: Read RG Keen's "The Secret Life of Pots". They can be wired as a voltage divider or as a rheostat. Some builds require 9mm, most require 16mm — get the 6.5mm shafts, not the 6mm, as most knobs are for 6.5. Note the split-shaft require press-on knobs but can take knobs with set screws, but smooth-shaft pots won't take press-fit and require set screw knobs.
Wire: 24AWG, tinned and pre-bonded
stranded — great if you want to do 1590A pedals down the road (or even 26AWG for such small builds), but stick with larger enclosures to begin with. I like to use multiple colours — red for power, black for ground and separate colours for input and output — it can help when trouble-shooting a complex build that has lots of offboard wiring.
Do
not buy solid-core, as it breaks and leaves you (needing) stranded.
Jacks: Always TOP-JACKS unless 1590A, but use whatever type-jack the build calls for which means open-ended for some, compact Lumbergs for others such as when the PCB is filling up the enclosure and leaves little space for your top jacks.
Power-jacks —
outties, 'cause then you can pull the entire circuit out of the enclosure should it need repair or trouble-shooting. Innies you need to desolder or have used a quick-(dis)connect and while they may look better on an unplugged pedal — that's lost once you plug in power and patch-cables. You should always "rock it before you box it", make sure the circuit is operational before stuffing it inside an enclosure, but sometimes that isn't practical or feasible.
Transistors & Op-amps: There's a lot of interchangeability of parts where a build can utilise substitutes and sound just as good (often saving you making a special order); also, most often the affordable commonplace part will perform just as well as so-called mojo parts if they're of similar performance-spec — so don't get sucked into buying needlessly overpriced vintage parts that might be out-of-spec or outright fakes. If in doubt, ask about the part/vender in the forums. MIND THE PINOUTS! Just because a different transistor will work well as a substitute doesn't mean it has the same pinout as the part it's replacing.
The common order of Op-amp pinouts, for example, is to start upper left corner of the IC and go DOWN the left-side and then UP the right-side in counterclockwise fashion.
SOCKET your transistors and op-amps — if you fry something and need to trouble-shoot or just want to try a different component it's easy-peasy to swap.
Start reading spec-sheets and cross reference in the forums what people are talking about. Some things in spec sheets aren't so important while other specs are critical.
MOST IMPORTANTLY — do what is right for you.
You'll develop your own methods, conventions, practices, and PREFERENCES that work for you. Some people like knowing everything they can about the whys and wherefores of what makes a single-transistor circuit tick, and others just want a cool-sounding pedal and don't care if the build is complex so long as they follow the paint-by-numbers approach and get it right — theories and reading schematics be damned. Maybe you'll go insane and stuff simple boosts into oversized enclosures with side-jacks and solid-core wire — hey, if that's what flips your switch... May you find your own path swiftly, and enjoy the journey!