Speak & Math

[BazTraD]

I've aquired myself a speak and math.
I'm sure most of you guys have done one of these before. If so, could you give me some advice where to start.

I powered it up and pressed my thumb across the bottom of the resistors near where the wires are connected from the battery supply. When I do this the pitch goes down and the unit speaks in slow motion.
Can I capture this and manipulate it with a pot or something.
I also started going about the solder points with an open ended wire and found some buzzes from the first IC, but haven't got around to going around the whole board to check what happens.

Any advice would be appreciated.

[Circuitbenders]

Some people will just remove and replace a resistor from the cluster at the bottom of the board for a pitch control on an S&M but i've always found you get a more usable effect if you connect the centre lug of the pot to the solder point that acts as a body contact, and the other two outer lugs to two pins on the bottom left of the big chip at the top of the board (face down battery compartment towards you). You will have to put some resistors or preset pots in ine with the outer lug connections to stop the thing crashing at either end of the pitch range.

[hippyjon]

ive got the bend above working i was just wondering if anyone knew anymore bends on the speak and math. im quite new to circuit bending and a bit paranoid about probing round the circuit myself in case i fry it, it took me such a long time to find one id be gutted if i killed it.

how stable are the speak and maths? are they easily fried?

if anyone knows any bends or has links to other sites please post.

thanks

[iqoruvuc]

so long as you keep to the solder points that hold the main chips then I wouldn't worry about frying anything - just keep away from those capacitors.  They are very stable and great thing to bend straight away.  there is also this schematic

[iqoruvuc]

P.S. also check ghazala's book http://www.amazon.com/gp/product/0764588877 for a couple of extra bends too.  These are good fun to bend. 

[hippyjon]

  thanks for the schematic im trying these bends and having a bit of a probe myself if i find anything interesting ill put it up.

[hippyjon]

my speak and math seems to have developed a nasty hum, its not so noticable through the built in speaker (although it is still there) but as soon as i output it too anything through the jack out it becomes very loud. ive tried taking of all the bends and its still there .

anyone have any ideas?

[iqoruvuc]

I experienced this just as I finished my first speak and maths.  Sometimes I would turn it off and then turn it on a little later and it would be okay for a few seconds and then it would come back.  It turned out just to be low batteries!  Hopefully new batteries will sort your problem and my apologies if you have already tried this!

[hippyjon]

this hum is a persistent little bugger ive tired everything i can think of and still its there short of buying another speak and math i think im going to have to live with it 

[Circuitbenders]

Could be that the display is on its way out and is causing electrical noise. Does the display look brighter than usual or do you ever get two horizontal red lines displayed instead of normal numbers? That seems to be a sure sign of a display on its way out.

[Pehr]

Also see www.casperelectronics.com for mods like this :

[Circuitbenders]

I have a feeling that half those mods won't work on an earlier or later circuitboard revision but that circuitboard seems to be the most common.

[hippyjon]

so if i removed the display would it stop it.

i cant really tell if its brighter then ususal i cant remeber how bright it used to be!! never had the red line though.

[Circuitbenders]

well, its a possibility, bit of a pain in the arse to put the display back on again if thats not the problem though. Still sounds like some kind of grounding problem to me though

You should feel overwhelmingly grateful you've never seen the red lines of death.

[Griffin]

On that casper electronics S&M layout, what does the (+) stand for?