GCSE coursework

[MatthewHorsley]

Hi, I'm totally new to this forum so please don't shout at my foolish questions. For my GCSE coursework I am planning on making a variation of the Fuzz Face and I am still trying to get my head around some of the theory. Below is the schematic. Could some one please run over the theory involved in as much detail as possible. Any help would be much appreciated, thank you.

[Jason Stout]

http://www.geofex.com/Article_Folders/fuzzface/fffram.htm

[gez]

I wish I'd have had the internet when I was doing my GCSEs...if only for the porn!

[MatthewHorsley]

Thanks, this has been very useful.

[Paul Perry (Frostwave)]

I can see RG getting an A for his GCSE 

[Jason Stout]

I can see RG getting an A for his GCSE 

I certainly hope that's not the case.   Matthew, what is required of you in GCSE coursework?

[Paul Perry (Frostwave)]

I remember a couple of years ago, a UK student built a FX box for his GCSE & left it on a train, where it was blown up as a suspicious device. Please don't let that happen to you

[SonicVI]

I go to the Post Office in downtown Houston a lot, sometimes to ship pedals. The PO is inside a federal court building so you have to go through the x-ray and metal detector each time. They always ask me "what is that you got there?".  I imagine it looks a little unusual on the x-ray screen. I just say musical electronics and they let it through.  So, there you go if any of you are terrorists and want to blow up a federal building just tell them your bomb is a "musical electronics device" and you're good to go.   

[MatthewHorsley]

I certainly hope that's not the case.  Matthew, what is required of you in GCSE coursework?

OK, the AQA board expect me to take a problem (in my case overpriced guitar pedals) and then come up with a solution using system block diagrams. It has to include two seperate "types of circuit" e.g. we are taught to use a monostable and an astable for example (boring).

I have decided that the primary circuit will be the fuzz circuit but I will use a PIC chip (Periferal Interface Controller) to make the circuit sleep until a current is detected, thus saving battery life. This counts as a seperate circuit.

Could someone please run me over voltage feedback biasing in simpletons terms, as I did not quite understand RG's explanation. Also if someone could suggest a few simple modifications to the fuzz circuit and explain them it would be much appreciated.

[Paul Perry (Frostwave)]

I think RG's explanation is in fact the simplest (unless an explanation that is over-simplified, and wrong, is acceptable).
For exam purposes, maybe you would be better off with a simpler distortion fx, plenty of scope for discussing the effects of different diodes.
To use the monostable, her eis the Boss (or similar) bypass circuit.
Remember, the problem really isn't to make the best FX box, it's to get max marks on the exam. I'm not trying to be a smartss saying that, just remembering student days (of 40 years ago).

[MatthewHorsley]

Having gone over the entire circuit with my physics teacher (much more competent than my foolish electronics teacher), I now understand the circuit in its entirity. The only reason that I was not doing a simple counter circuit was that I felt that although it would get me easy marks, it would be the most boring GCSE project ever. This way I am able to test my ability. Thanks for all the help (geofex.com was particularly useful. I am not stupid enough to plagurise after putting the website down as one of my sources of information!). Once I have recieved my mark (around next September I think) I will post it on the internet so you can all marvel at my high A*. 

[Paul Perry (Frostwave)]

Having gone over the entire circuit with my physics teacher (much more competent than my foolish electronics teacher), I now understand the circuit in its entirity.

Well then, you're a better man than I am, Gunga Din!

[Eric H]

Having gone over the entire circuit with my physics teacher (much more competent than my foolish electronics teacher), I now understand the circuit in its entirity.

Well then, you're a better man than I am, Gunga Din!

beat me to it again, Paul.

[Eric H]

I remember a couple of years ago, a UK student built a FX box for his GCSE & left it on a train, where it was blown up as a suspicious device.

Years after college, a story like that will be far more useful than any coursework you can remember.

-Eric