freestompboxes.org

I am about to order the parts for my first build, an EP Booster clone. This is supposedly an easy build, which is good as I have zero experience in building electronics.

After some research, I have decided to use this veroboard schematic.



So far I think I have done a decent job at "translating" the layout into a parts list, but I wanted to run it by those more experienced to make sure I don't miss anything.

General Stuff
Vero Board
Knobs (×1)
SPST On-On Switch (×2)
Enclosure (1590A or 1590B?)
Wire
Mono Jacks (×2)
LED
LED Bezel
3PDT Switch
9VDC Jack

Resistors
100R
1K
4.7K
8.2K
10K (×3)
15K
33K
47K
1M (×3)

Capacitors
3.3nF
47nF
10uF (×4)
100uF (×2)

Not Sure What These are Categorized As
J201
2N5088
1N4148

Pots
C10K

Also, I had a few additional questions. Should I use metal or carbon film resistors? What type of capacitors should I use (I am overwhelmed by the many different types)? Do you think this will fit in a 1590A enclosure (with external SPST switches for the bass/treble boost) or will I need a 1590B? Should I use a PCB mount pot? How many colors/how much wire should I order? Do I need any additional components for offboard wiring? What should I use for wiring across the different "strips" of the veroboard?

Sorry if this is a lot, but there is a lot to think about and it's kind of overwhelming...

Hi Troll1

Welcome aboard. I hope your build goes great and works first time.

In your parts list you've changed the SPST switches from simple Off-On to On-On, which would make them SPDT. They'll still do the job.

The J201 and 2N5088 are transistors, and the 1N4148 is a diode - but they could all be classed as semiconductors.

The C10K pot may be hard to find.

I haven't checked your full component list, as I assume you have done that correctly (I'm sure you've checked it a couple of times yourself).

As to your other questions:

Resistor type shouldn't matter on this type of build. I prefer metal film, but either type will do.

Capacitors: 10 and 100uF are electrolytic. Get the 'stand-up' type with legs at the same end. Just make sure you put them the right way round (ie, +ve where shown on the diagram).
Other caps - try the metal film box ones (usually yellowy coloured) - but any other non-electrolytic type should do the job. Just make sure the distance between the legs (pitch) suits the distances on your board.

Box: Go for the 1590B. I don't have the dimensions of the 1590A to hand, but I don't think it would all fit. The 1590B is a standards pedal size, and will give you plenty of room to get your soldering iron in without frazzling everything.

PCB mount pot: I'd go for a normal pot for now. If your box drilling is out, a PCB type can cause you problems (like pushing your board to one side so it doesn't fit properly.

Wire: Some people prefer to get one big length of wire, so all their wiring is in one colour. While this can look pretty cool, it makes fault-finding VERY difficult. I personally use as many colours as I can, reserving red and black for the power connections. I tend to use yellow for my input and blue for the output on ALL my pedals, but you may have different preferences. If you intend to build pedals for years to come, then you could invest in a 100m reel of each colour - it works out far cheaper in the long run. Otherwise I'd just get a couple of metres of each colour for now. You can get single-strand or multi-strand. Different people have different preferences, but for pedals I prefer single strand.
Components for off-board wiring: The only ones I'd use are pins to go on the veroboard. I prefer to solder my wires to pins than to pass them through the board for soldering to the tracks/traces. Correct fitting pins may be difficult to find, so you may prefer to wire directly to the board.

Wiring (links) across the different strips of the board: You could use the same wire that you use for your off-board wiring, but the insulation tends to melt, and things can look tatty. If you can invest in a reel of tinned copper wire (TCW), get 22swg (preferable) or 24swg (a bit thinner). Cut a length of 300mm say, and stretch it between two sets of pliers so the kinks drop out. You'll then have nice straight wire to make your links. Mostly these can be left uninsulated, but any links spanning more than say five tracks, I usually cover with silicone sleeving to make sure the link doesn't accidentally touch the leg of another component.

I hope the above helps - but if you need any more info, just yell.

Good luck

Very comprehensive answer, Lucifer -

Lucifer wrote:Resistor type shouldn't matter on this type of build. I prefer metal film, but either type will do.

Resistors also come with power ratings: 1/4 watt is plenty big enough for 9 volt circuits, and larger power rating means bigger + bulkier resistors.

Lucifer wrote:Wire.... .....You can get single-strand or multi-strand. Different people have different preferences, but for pedals I prefer single strand.

Wiring (links) across the different strips of the board: You could use the same wire that you use for your off-board wiring, but the insulation tends to melt, and things can look tatty.

Single strand is less flexible and more likely to break at the board connections, so I prefer stranded for off board connections. However, if you buy just a couple of metres of one colour of single strand, you can strip the insulation and use this for links across the veroboard.

Wow, thanks a lot! This is really helpful, and cleared up a lot of my concerns. I'll update this thread once I get a good start and if I run into any trouble along the way.

As I look there are different voltage ratings on the radial capacitors (50V, 100V, and so on). The schematic says 16V+ ...does this mean that any voltage rating above 16 will work?

http://www.taydaelectronics.com/catalog ... lt/?q=10uf

Also, mylar or polyester film capacitors for the box types?

http://www.taydaelectronics.com/catalog ... t/?q=3.3nf

Yes, 16 volts or higher. 16v is plenty big enough for a 9 volt stompbox.

The polyester film are the "box caps", though plenty of people use mylar too. The main advantage of box caps is they are generally smaller than mylar, and are more consistant in the lead spacing (i.e. always a 5mm/two veroboard hole span) whereas mylar can vary depending on values. Mylar are much cheaper though, so it's up to you.

I just finished populating the PCB and it went without problem, but I have hit a road block of sorts. The C10K pot I ordered is a PCB mount (as opposed to one with solder terminals), and I didn't realize it.

My question is, how exactly do I solder this pot to the board? I figured I should just insert the tabs of the pot into the according holes in the vero board (there is room and everything lines up as intended) and then add solder, but this doesn't seem to be the case. The tabs are too big for the holes. Also, the tabs come straight out of the pot, whereas I need them to be bent down at a 90° angle so it will fit correctly in the enclosure. Do I just take pliers to the tabs and bend them down? Should I drill bigger holes in the vero board so the tabs slide in, or force them in so it's a tight fit? Thoughts?

You *can* carefully bend the pins with pliers, and they will fit the vero holes with some encouragement. However, I wouldn't advise it: It's easy to snap off the pins and then the pot is useless. The other problem with mounting the pots on the board is that you'll end up with the lugs reversed from how they need to be - That is to say that with the pot shaft facing away from you, and the pins bent "forward" so they slot into the marked pot connections on the vero, your pot lug 1 will line up with the vero hole for lug 3, and your pot lug 3 will line up with the vero hole for lug 1: The central pin will be in the appropriate hole. This will mean the pot works in reverse, i.e. counterclockwise for more volume boost. Also, desoldering a board-mounted pot from vero is a nightmare.

Although the spacing for the pot connections happens to be correct for 16mm pcb-mount potentiometers, I'd advise using wire to connect the pot: You can just solder an appropriate length of wire to the board, then fashion a "hook" at the other end of the wire, loop it around the pcb-mount pin, squeeze it with pliers to hold it tight to the pin, then solder in place.

Yeah, I was thinking this might be a possibility as well. Is this common practice? How solid will the connection be?

Plenty solid enough. As long as there is no mechanical stress on the wire, and your soldering is decent, the electrical connection should be no different to the connection to a solder lug-equipped pot. I think it's a fairly common practice.