Beavis Board, building your own

[MrForbes]

Hi,

I am a high school teacher who teaches senior physics.  Circuits are part of the curriculum and I have used some simple breadboard stuff in the past.  The kids really think it is cool but you can  only be so motivated by building LED displays.  I am a guitar player too and have my es335 and my fender deville 210 in my room all year round.  Many of my students have an interest in pedals so I thought it would be cool to build some "Beavis Boards" so that they could experiment with.  I know the beavis board is out of production but I have read that it is not that complex to build it if I get all the components.  If anyone could help me with this that would be great. 

Darren Forbes
Carpenter High School
Meadow Lake, SK
http://www.nwsd.ca/schools/chs

[caspercody]

I made up my own version of the Beavis Board by just using a Radio Shack box and wiring it up like this

http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_ig_dcjack.gif

Then I have four wires coming out of the box to my breadboard. Input, output, ground, and voltage. The ground and voltage go to the (-) and (+) on the board, and the input and output wires I left long so I could just insert the lead into the breadboard. I also included a 100K pot in my box, this is the lead for the output.

Hope that helps

Rob

[deadastronaut]

+1 all my breadboards are fitted with a 3pdt 'toggle' with led , and in/out jacks , and a 9v socket all built onto the backplate,

with just in out wires and positive/ground going to the breadboard...truebypass etc...essential for prototyping.....

plug in and go...

[waltk]

If you decide to move forward with this idea, I just have a couple suggestions for you...

I assume you have a finite budget for this sort of thing.  Don't be stingy with the quality of jacks.  The cheap jacks break or develop bad contacts; buy Switchcraft or Neutrik brand.  

Save yourself some money by using 3PDT toggle switches instead of stomp switches.  The stomp switches are much pricier, and the toggle switches are better for a benchtop environment anyway.

If you design a minimal voltage regulator (using a 7809) inside the box, you can use cheap unregulated wallwarts for the power supply.

[smallbearelec]

This has been done, and in various forms. Some people slap a small breadboard down in the middle of a cast aluminum enclosure (in place of a circuit board) and build the off-board components around it. Set up the circuit on breadboard, wire to switch and jacks, and the result is something suitable for gigging but also easily modded.

Check out my Stock List for the pieces you would want:

http://www.smallbearelec.com/StoreFront.bok

and drop a message to smallbearelec@ix.netcom.com if you have other questions.

Regards
SD

[MrForbes]

Thanks for the replies.

I am for sure going ahead with this.  I already have a bunch of jump wire kits and breadboards.  I will have to build something fairly sturdy to survive student use and for a few years down the road.  I was thinking at least two (maybe three) potentiometers.  I was going to dedicate a breadboard to each potentiometer (Does that make sense?).  This way it leaves it open for more advanced students to expand their projects.  In general, the students are pretty keen.  Most physics equipment is crazy to buy...in the thousands of dollars range.  Most of the stuff I use I have hacked together for them to use.  This project will be no different.  i will be able to spend some money I am sure but I will make up the difference if I have to.  Physics, especially electricity, can get pretty boring just learning the theory.  I am looking forward to the feedback here and I will post results as we go.  Should be an adventure!

Darren

[waltk]

I was going to dedicate a breadboard to each potentiometer (Does that make sense?)

...or you just solder a jumper to each terminal of the pots (use different colors for pins 1-3), and let the students plug them into a single breadboard wherever they like.  If the pots are mounted on a metal plate or chassis of some kind, you could drill a hole for the jumpers for each pot - and use rubber grommets to prevent the jumpers from chafing against the sides of the holes.  For instructional purposes, it might be best to use a flat metal plate to mount the pots so that the back side is exposed and visible to the students.  You could even let them swap different pots on the mounting plate. (Maybe keep a box of pre-wired pots.)

[MrForbes]

actually that is a great idea about using a plate to keep the back exposed.  We have a welding shop so i could get some plate from there.  Sweet.

Darren

[waltk]

Welcome to DIYStompBoxes.  Be sure to let us know how it goes, and post some pics when you have something to show.

[MrForbes]

I will get you updated as i go as I am sure I am going to need some help

Doing some reading online and ordered some books to help.  I can wire a house like it's no tomorrow but circuits like this are another story.  I actually went to Luthier school too (besides going to university and becoming a teacher, which is more stable than building guitars) but I specialized in acoustic guitars and only ever learned the basics of of electric guitar wiring.  The students are already pumped and I have about until May to get this stuff up and running for them.  I will post pics too as i go.

Darren

[DavenPaget]

I will get you updated as i go as I am sure I am going to need some help

Doing some reading online and ordered some books to help.  I can wire a house like it's no tomorrow but circuits like this are another story.  I actually went to Luthier school too (besides going to university and becoming a teacher, which is more stable than building guitars) but I specialized in acoustic guitars and only ever learned the basics of of electric guitar wiring.  The students are already pumped and I have about until May to get this stuff up and running for them.  I will post pics too as i go.

Darren

We are all here to help you out 

[davent]

Was looking for a decent way to deal with pots for my Beavis Board clone, hanging off the board, needing two hands to manipulate them wasn't doing it for me. A work in progress... this is what i've come up with so far. When i ordered this breadboard my intent was to cut the board in half so i had two long strips and make two pot board setups. The web dividing the halves was too narrow and i figured i could end up with two destroyed strips so left it whole and as it stands i've got a breadboard that deals with the pot issue and has plenty of room to create simple circuits on.

Still have to add a jack for the power supply but this is how it's evolved so far. Only issue so far is the long rail under the pots is not very accessable, hadn't originally planned to use it but it'd be useful as the second power rail.

The pots can be easily changed, just plug into the board then tighten the nut up. Needed to solder thin leads (resistor cutoffs) to the pots so they'd fit the breadboard holes.

[MrForbes]

Actually this gave me a great idea!  Thanks for sharing!

[alex_spaceman]

not long ago i did my simple version of it.
easy as pie to prepare and oh so useful!

here's a little thread with a couple of (blurry) photos: http://www.diystompboxes.com/smfforum/index.php?topic=95970.0

[MrForbes]

Ok, so I am going to build some boards with the potentiometers built in (4 of them).  Now if I want the potentiometers to mimic potential knobs on a pedal, what kind of potentiometer should I use?  I assume a linear type.  However, is there a standard rating knob that is used (for example B500K) or will it depend on what you want the knob to control in the circuit?  having said this, given a "dream" inventory list to start with for 5 setups, what would I buy to outfit myself?  I would love your feedback on pots, capacitors, transistors, diodes, switches, chips, etc. that you would have on hand to basically let these kids prototype pedal circuits.  I have multimeters and the breadboards.  I also have a lot of tracer wire too.

I also will do my best to my all the parts from this site since I can pay with paypal.  Very cool.

[PRR]

> boards with the potentiometers built in

Build-in the holes. Not the pots.

[MrForbes]

I might leave holes. After reading some schematics I see the pots used do change depending on the function.

I would like to have a "dream" list of parts to have for these prototype boards that I could get from this site!  Make you suggestions! 

[artifus]

http://www.geofex.com/effxfaq/keenslaws.htm

[MrForbes]

http://www.geofex.com/effxfaq/keenslaws.htm

This was a very good read. Thank you.

[davent]

Since this started with the Beavis Board i'll go back there so here's the overview of the parts that were included with a purchased Beavis Board.

http://beavisaudio.com/bboard/parts.htm

By no means do you need all the flavours of dual op amps listed, same goes for the BJT's but then those are so cheap ...

The Beavis Board Document http://beavisaudio.com/bboard/docs/HackersGuideToTheBeavisBoard.pdf

...and Beavis Board Projects http://beavisaudio.com/bboard/projects/