Instructables

Need some advice on fixing power issues with my instructable

So I built an Atari punk synth using instructions on this site and made it a bit more advanced. It has six 555 timers and button controls. Now I would like to power this thing with a 9volt wall plug, the same thing I use for my effect pedals, but I have crazy power issues when I set it up this way.

It works fine when I just use a 9 volt battery, but when it's set up to be used with a 9 volt wall plug it seems like its getting way to much power. The sound goes crazy and it blows out my LEDs even though I have resistors on them. I've tried putting a resistor on the power jack, but it doesn't sound right when I do that and it still doesn't work right.

So I'm curious what's exactly going on here. Regular effect pedals that run on 9 volts work fine with the wall plug and even the instructables on here say you can use them. But for some reason this thing only will work with a battery. Could it be the parts I'm using? I have a feeling it has to do with wattage and my parts just can't handle it. 

Any advice would be greatly appreciated. 

Y'know the way some transformers give you a hum with FX pedals etc.

Seems to be cheaper wall wart ones can have pretty bad regulation - voltage as said in other comments but also the voltage often wavers up and down a little, giving the hum, far as I know, bad rectifying is the cause.

One solution might be to add a regulating circuit of your own, or find a better made transformer.

I had to work for ages on a recording from the studio to fix a hiss - caused by the transformer on a vocoder...
+1 add a regulator. And my own 2 cents worth: make sure to eliminate as much ripple as possible. I am curious as to how you are powering 6 power hungry 555's on a 9 v battery though.
Anything that outputs a really clean DC voltage and cover the power needs...

More your area than mine - I know the problem, so I pick one out of the pile - if I could sort a voltage to same regulator - or anyone else, it'd be a big hit in the music and studio world, plus I'd always know it was their jack cable. (Sound often comes down to fine the problem, all the cabling adds a million problem points)
We may be thinking differently: if by "regulator" you meant a device, I was thinking more along the lines of a componant, like the 7809 which will give you a ripplely DC output at best if inserted alone. The other componants shown help with smoothing out that ripple:
I was thinking of what would essentially be a small power cleaning circuit... To give smooth DC to the electronics...
...of which a 7809 regulator IC could be a part :-)
Funny how a regulator would have a regulator in it...
Different perspectives: the whole orange as opposed to a slice. Both are "the orange". :-) The regulator in a regulator isn't "quite" like the "little guy operating your brain as a control center" because that little guy also has a brain, and his brain would be operated by a still smaller controller.....etc etc.
Unless you have a regulator on it you could be getting anything the time of day can affect the output during peak usage times.
Joe
Use a meter and measure the wall adapter. I've often found cheap 9V wall adapters will actually put out as much as 15V. If it is in fact outputting more then 9V you'll need more then a few resistors to make things work. You'll want to get a better regulated wall adapter or buy a voltage regulator to put between your power source and the atari punk console.
wickednick (author)  mpilchfamily1 year ago
Probably right on that, I found some other sites that said the same thing to about adapters. What I'm curious about though is why do my effect pedals have no problem with the adapters, but my punk console does? Are the effect pedals just built with parts that can handle more voltage?
I'm curious because for future projects I would like to be able to avoid the issues I'm having now. So I'd like to get some advice on how I can build my devices better so they can better handle being plugged into a 9V adapter.
Look at the label on the adapter. It is rated for 9V @ a max of so many mA. Your pedals are putting a heavy enough load on the adapter to keep it close to it's max amperage output so the voltage is about 9V. If you don't put much of a load on the adapter the voltage output starts going up. Those adapters are not regulated power supplies. They will fluctuate based on many conditions. The punk console isn't pulling more then a few mA from the adapter. It's not putting a large enough load on the adapter for it to limit the output to 9V. So you either need to add a voltage regulator to the circuit or get a regulated adapter. Not one of the cheap ones that is little more then a transformer and rectifier.
wickednick (author)  mpilchfamily1 year ago
Ok, that makes sense. Thanks.
+1 Add a regulator.

The 9V is stated at full load. Off load, all bets are off.