Download B.Y.O.C. overdrive kit build instructions

B.Y.O.C.
overdrive kit
build instructions
page 2 - 3 ...............................................Parts Checklist
page 4 - 8................................................Modifications
page 9 - 12..............................................Populating the Circuit Board
pages 13 - 14..........................................Assembly
page 15 - 16............................................Wiring
page 17 - 18............................................Installing the LED
page 19...................................................Finishing Up
Parts Checklist
Resistors: (resistors may be 1% metal film which have a light blue body or 5%carbon
film with a light brown body)
1 100ohm (brown/black/black/black/brown or brown/black/brown/gold)
1 220 ohm (red/red/black/black/brown or red/red/brown/gold)
1 470ohm (yello/purple/black/black/brown or yellow/purple/brown/gold)
4 1k (brown/black/black/brown/brown or brown/black/red/gold)
1 1.5k (brown/green/black/brown/brown or brown/green/red/gold)
1 2.7k (red/purple/black/brown/brown or red/purple/red/gold)
2 4.7k (yellow/purple/black/brown or yellow/purple/red/gold)
7 10k (brown/black/black/red/brown or brown/black/orange/gold)
1 20k (red/black/black/red/brown or red/black/orange/gold)
1 51k (green/brown/black/red/brown or green/brown/orange/gold)
1 100k (brown/black/black/orange/brown or brown/black/yellow/gold)
2 510k or 511k (green/brown/brown/orange/brown or green/brown/yellow/gold)
1 620k (blue/red/black/orange/brown or blue/red/yellow/gold)
1 4.7M (yellow/purple/green/gold)
Pots:
1 25kB pot (tone)
1 100kB pot (level)
1 500kA pot (drive)
Capacitors:
1 51pf ceramic disc (small round orange)
1 .022uf film(223)
1 .047uf film(473)
2 .1uf film (104)
2 .15uf tantalum (small yellow dipped)
1 .22uf film (224)
2 .22uf tantalum (small yellow dipped)
2 1NP NON-polarized electrolytic
2 1uf film (105 larger box shaped caps)
1 10uf aluminum electrolytic
1 47uf aluminum electrolytic
1 100uf aluminum electrolytic
Transistors:
2 MPSA18
Diodes:
3 1N914 or 1N4148(small orange with black stripe)
3 1N4001 (large black with silver stripe)
3 small red LED's
IC's:
1 JRC4558D
1 RC4558P
1 8 pin socket
Hardware:
3 self adheasive nylon standoffs
3 knobs
1 heavy duty battery snap
1 Red T 1 3/4 (5mm)LED
1 3PDT footswitch
1 1/4 mono jack
1 1/4 stereo jack
1 AC adaptor jack
1 125b size enclosure
1 Overdrive PCB
Hook-up wire
Approx. 30 snap off sockets
Modifications:
We'll start with an explanation of what some of the mods are and how to do them so that
you'll get a better idea of how you want to build your overdrive. However, I would personally
suggest building the pedal stock and then going from there. Use the snap off sockets if you
plan on experimenting a lot, but keep in mind that the larger diodes and the 1uf film capacitors
will not fit in those sockets.
1. Changing the resistors:
a. 4.7k - This is the maximum distortion resistor. Replace it with either the 2.7k or the 1.5k
for more distortion. The pedal may get noisier and feedback a little bit if you go too low.
b. 51k - This is the minimum distortion resistor. Replace it with the 20k toincrease the
pedals ability to clean up.
c. 510k - Input impedence resistor. A higher input impedence is better for guitar FX.
Replace it with the 620k. You can go even higher if you want. Try a 1M.
d. 10k & 100ohm These are the two resistors that seperate the TS808 from the TS9.
Generally, TS808 specs are more desired and they are what will will consider stock for this
build, but if you want 9series specs, here you go. Replace the 10k with 100k and replace the
100ohm with 470ohm.
2. Changing the Capacitors:
a. Before you start, notice the 100uf cap highlighted in red. The 1uf film caps are physically
larger than the 1NP electrolytics, so if you leave the 100uf cap sticking up out of the PCB just
a little bit when you solder it, this will allow you to bend it out of the way enough to fit the 1uf
film caps.
b. Replacing the 1NP electrolytics with the 1uf film caps is done for improved audio fidelity.
c. Replacing the .22uf tantalum caps with .15uf is done to shift the frequency response of the
tone knob into a more guitar friendly part of the spectrum.
d. Replacing hte .047uf film cap with a larger value cap will increase bass response and
reduce with midrange hump of the frequency curve. Use either the .1uf or .22uf film caps.
3. Clipping:
The clipping section is probably where you will do most of your experimenting. There are a
lot of different things you can do here. Slight modifications to the clipping section are what a
lot of boutique builders claim make their overdrive different from anyone elses. We're just
going to cover some of the basics here, but there are literally thousands of different
combinations to try.
Just a note about using LED's as clipping diodes. LED's are dioded. L.E.D. stands for light
emitting diode. It has two ends just like a regular diode: the cathode and the anode.
a. Symmetrical clipping:
Symmetrical clipping will reqire you to jumper one of the larger diode slots and use 2 of the
same types of dioded. Stock TS808 specs would use 2 of the 1N914 diodes. People will often
discribe this type of clipping as sounding more compressed . Another very popular
symmetrical clipping mod is to use two red LED's. People often describe this clipping style as
being punchy or cruncy or sometimes say it makes the pedal sound more marshall-like .
b. Asymmetrical clipping:
Asymmetrical clipping means that on one side you have one diode facing one direction and on
the other side, you have a different type of diode or diodes in series facing the opposite
direction. Guitar players seem to prefer asymmetrical clipping over symetrical clipping.
Asymmetrical clipping is usually described as sounding more open, less compressed, and more
tube like than symmetrical clipping. This is were you can really get creative. Is pretty good
combination is 1 1N914 diode on one side and 2 1N4001 diodes in series on the other side.
The PCB was designed for this combination, so it also fits nicely.
4. Using a different OpAmp
Operational amplifier (OpAmp), Integrated circuit (IC), and chip are some of the names given
to this component. The kit comes with an extra op amp to try out. It's kind of like changing
tubes in your amp. Just pull the old one out of the socket and plug the new one into the
socket. MAKE SURE YOU DO NOT PUT THESE IN BACKWARDS. If you do you will
fry the chip. You can use just about any type of DIP 8 dual op amp you can find. Don't be
afraid to experiment here either. They can even be JFET or MOSFET op amps. As long as
the chip in question is a physical match, just go ahead and plug it in and see how it sounds....it
won't hurt anything.
This is an exampl of a DIP8 package IC and DIP8 socket.
5. Running at 18VDC
The concept is simple. Just use a higher voltage power supply. The higher the voltage the
more headroom you will have. This is a good thing if you like to use your overdrive as more
of a boost than a distortion. You don't need to do anything special. Just make sure that the
power supply you are using is DC and negative tip. All of the capacitors are rated for at least
25v, so you can use anything between 9 -18VDC safely.
Populating the Circuit Board (stock TS808 specs)
Step 1: Install the diodes for ts808 specs. Only add two of the 1N914's (the small orange
glass with black stripe) as shown in the diagram below. One 1N914 goes in the small diode
slot. The other goes in a large diode slot. Be sure to orient the diodes so that the striped end
matches up with the striped end on the PCB layout. Jumper the open diode slot with a piece
of leftover clipping from the leads one of the diodes.
Step 2: Add all of the resistors. These are not polarized and can go in any direction. Color
codes are in the parts checklist. Take your time...as always...but especially here. When
people make cold joints, it's usually on this step. Socket any of the resistor values you'd like
to experiment.
Step 3: Add the 8 pin IC socket. Match up the u shaped cut out on the socket with the u
shape on the layout. Do not install the IC into the socket yet.
Step 4: Add the ceramic disc cap and the tantalum caps. The ceramic disc cap is not
polarized and can go in any direction. The tantalum caps are polarized. The longer lead will
go in the square solder pad. If your tantalum caps don't have a positive lead that is longer than
the negative lead, it will have a
symbol printed on the cap is self which denotes the
positive side.
Step 5: Add the transistors. Be sure to match them up with the shape printed on the PCB
payout.
Step 6: Add the film caps. These are not polarized and can go in either direction. The
.047uf cap is a good one to socket for experimentation.
.
Step 7: Add the aluminum electrolytic capacitors. These are polarized. The positve end will
have the longer of the two leads and go into the square solder pad. The negative end of the
cap will have the shorter or the two leads and will have a stripe going down the side of the
capacitor body. The negative lead goes in the round solder pad. The 1NP aluminum
electrolytic caps are not polarized. the NP stands for non-polarized. So these can go in either
direction dispite the fact that there is a
symbol and square solder pad to one side of the
component space.
Assembly
1. Install the jacks first. If you are looking down inside the enclosure, the mono jack goes on
the right side and the stereo jack goes on the left. Place the washer on the outside of the
enclosure. Use a 1/2" wrench to tighten.
2. Install the AC adaptor jack. The bolt goes on the inside. Use a 3/4" or 14mm wrench to
tighten.
This is a disconnect ac adaptor jack. That means that when you have a battery connected
and you plug in the adaptor, it will disconnect the battery. That is why there are 2 positive
terminals. They are both connected when there is no plug in the jack, but when the plug is
inserted only one of the terminals (the uppermost terminal in the back view ) is connected to
the sleeve of the adaptor. The advantage of this is that you can leave batteries in your pedals
as a back up power source if you are a working musician and they will stay fresh even when
you have the input jack plugged in as long as you keep the adaptor plugged in.
3. Install the potentiometers so that the solder lugs are pointing down towards the footswitch
side of the enclosure. Use a 10mm wrench to tighten but only snug. Do not over tighten the
pots.
4. Install the footswitch. The first bolt and metal washer go inside. The plastic washer and
second bolt go on the outside. It does not matter which side you designate as the "leading
edge" of the footswitch as long as you orientate it so that the flat sides of the solder lugs are
aligned in horizontal rows, not vertical columns. Use a 14mm wrench to tighten.
Wiring
Step1: Wire the pots to the PCB. The PCB eyelets are all double sided, so you can thread
the wires in from the bottom side and solder on the top. But be careful to make sure that you
are matching up the correct solder eyelet with the correct pot lug.
Lets take the Tone knob for example. The corresponding solder eyelets for the Tone pot all
start with the letter
. T1, T2, and T3. T1 gets connected to lug 1 of the tone pot. T2 gets
connected to lug 2 of the tone pot. And T3 gets connected to lug 3 of the tone pot.
Then we have the Volume knob. All the corresponding solder eyelets for the Volume pot
start with the letter
. V1, V2, and V3. V1 gets connected to lug 1 of the Volume pot.
Ect, ect, ect.....
Step 2. Now wire up the rest of the pedal following the diagram below. The labelling on the
solder eyelets should make it fairly intuitive, Note that the view in the wiring diagram shows
the pots with their back facing you as if you were looking down inside the pedal enclosure.
Installing the LED & mounting the PCB
Insert the LED into the UNDERSIDE of the PCB, but DO NOT SOLDER IT. Make sure
the longer lead goes in the round hole and the shorter lead goes in the square hole. No, this is
not a typo. Yes, this is contradictory to the way most other componets go in the circuit
board.
The positive end will have the longer lead just like the other components, but this time it goes
in the round solder pad. The negative lead will have the shorter lead, but this time it will go in
the square solder pad. Notice that the negative side is flat. On diodes the negative side is
called the cathode and the positive side the annode.
1. Insert the LED into its slot on the underside or solder side of the circuit board,but DO
NOT SOLDER it yet.
2. Once you have the LED in place, bend the leads a little bit so that it will not fall out when
you turn the PCB over.
3. Install the nylon circuit board standoffs into the mounting holes.
4. Remove the paper backings on the standoff to expose the self-adhesive tape.
5. Insert the LED bulb into the LED hole in the enclosure by guiding it in with the excess
leads sticking out of the top of the PCB..
6. Secure the Standoffs to the back of the potentiometers.
7. Your LED should still be free to move up and down slightly. You probably do not want
your LED sticking all the way out of the hole. So pull up on the LED legs till you have it
properly positioned and then solder.
8. Clip off the excess LED leg wire.
.
Finishing Touches
1. Install the IC. You must line up the U-Shapes!!!! Some IC's won't have a U-shape. If
they don't then they will have a small dot in one corner. This dot represents pin #1. The dot
on the IC should be on the same side as the U-shape of the socket. IF YOUR IC HAS BOTH
A U-SHAPED NOTCH AND A DOT ALWAYS USE THE U-SHAPED NOTCH TO
ORIENT THE IC.
2. Install the base of the enclosure with the 4 screws that came with your kit.
3. Add the rubber bumper feet...unless you're a velcro person.
If you've got any problems that you can't figure out yourself, visit
www.board.buildyourownclone.com
for technical support.