Behringer UV300 Rate Mod (Slow Down)

I thought I'd take a quick venture into modifying a effects pedal. The one I chose was the Behringer UV300 ( Ultra Vibrato ) I love Behringer gear and in most cases they do a really good job at effects and pretty well everything they put their minds to (see the X3!)
anyway I bought this on a whim cause it was very very cheap, I didn't even bother looking for samples because if I'm honest there is only so many times one can watch people doing out of tune covers of Lucy In The Sky With Diamonds while reviewing Vibrato pedals - also they never turn the rate down to nothing to show you how slow it goes.

as you can probably tell by this post, the "rate" didn't go as slow as I wanted, I like that sort of hypnotic warped record vibrato which this pedal couldn't do however with a little knowledge of how oscillators work and a bit of time probing around with a scope I was able to modify this to go slow enough

In order to slow down the range of the Rate control you basically just have to add capacitors in parallel with C12 and C15 - or you can swap them completely for higher values - the higher you go the slower it is however you need whatever capacitors you add to be very close in value to each other because if one is very different you get an uneven vibrato.
anyway here are the pictures.

if you have any questions - ask!

and you don't need to rehouse behringer pedals, the plastic is very strong - it easily withstands being dropped down stone stairs many times.

solder very quickly otherwise you'll be resoldering SMD stuff!

it's a good idea to do this in order to tailor it to your preference

the part of the circuit I am changing

The Behringer UV300 with its nice new switch

Devils Triangle Drone Synth Stripboard Veroboard Layout

this is a project based largely on the put up or shut up mentality, for quite some time I've been getting annoyed at seeing youtube videos of people pissing about with these "synths" which are basically boxes of 555 timers with a million knobs that make stupid noises that you couldn't ever actually use in music so I thought I would make my own little synth that would get repeatable sounds and be useful in music and what better type of synth? a droner type - basically cause I love bagpipes - I like drones
anyway the circuit itself is quite a simple one basically because I only designed it during the week, all it is really is 3 triangle wave generators configured to operate in the audio range going into a mixer op-amp configuration with the odd filter here and there to soften the waveforms
I've used LM358 op-amps cause they are the cheapest, I'm not too sure if others would work in the same way though they probably will.

why call it the devils triangle - well it has 3 oscillators one of which can oscillate a slightly high pitch range (for melody) it also sounds demonic so the name fit

Hope you enjoy

EDIT: I replaced the level knobs with on/off switches - it makes it so much more versatile being able to silent certain drones 
EDIT: I added a little schematic on how the switches should be wired as it was causing a bit of confusion.

the one I made - with a really shit paint job

Flux Capacitor LED Decoration Stripboard Veroboard Layout

for fans of Back To The Future - or LEDs
I know this isn't exactly like the real thing however that would involve crux tubes and so on and I doubt many people who read my site want to piss about with 10,000 volt supplies. Anyway it's pretty much for my halloween/christmas/bonfire night decoration collection.

as you can see I have included a layout for the actual display board, although it looks like the LEDs maybe abit too spaced out, in practice they wouldn't fit when they are closer together. However should you just want to use the display board I think that each transistor can drive quite a few LEDs (I think the 2N3904s are rated at 100mA)
As it stands the circuit draws roughly 5mA

The last thing I want to mention is the odd value electrolytic (well odd to some) it is 470nf however you can use a none polarized version it just happened that I have both kinds and the electrolytic takes up less space

I also included a little video to show you what it does. HERE

Paul in the
Lab is here to help
Everyone that's into electronics
Always feel free to
Seek my advice
Either using the
Contact button or my email
Lately I am always at the computer because
I am  designing stuff for the site though I did buy a new
Camera recently it's pretty cool. I remember the first thing I built was the
Knight rider LED scanner which I uploaded
To the site a few days ago, remember if you need to know
How to do something
Even if you think it's
Abit of a stupid question just ask, I
Don't mind. We all had to
Start somewhere. 

Fading LEDs / Eyes for Halloween decorations stripboard veroboard layout

The inspiration for this little circuit with Halloween approaching was a post I saw made on this Thrifty Crafty Girl
basically the girl had an idea of putting glow sticks in toilet rolls with eyes cut out to leave in bushes however I thought it would be cool to add an electronic element to it.
so I made a little circuit that will make LEDs fade in and out - they will go in and out of sync and will look pretty dam creepy
Anyway this one quite cheap to make circuit will "power" 4 toilet roll monsters - 2 LEDs per toilet roll or whatever you want to put "eyes" or LEDs in
below is a video of it in action

Paul in the
Lab is here to help
Everyone that's into electronics
Always feel free to
Seek my advice
Either using the
Contact button or my email
Lately I am always at the computer because
I am  designing stuff for the site though I did buy a new
Camera recently it's pretty cool. I remember the first thing I built was the
Knight rider LED scanner which I uploaded
To the site a few days ago, remember if you need to know
How to do something
Even if you think it's
Abit of a stupid question just ask, I
Don't mind. We all had to
Start somewhere. 

Voice Bandwidth Filter for podcasts / youtube veroboard stripboard layout

This idea came about when someone was tweeting on twitter that they were having problems with rumble noise and high pitch squealing from some air conditioner unit. So I thought I would make a filter for people to combat such problems, basically this thing attenuates anything below 300Hz and anything higher than 3KHz which is pretty much everything outside of the vocal range.
This could be a useful thing to combine with the high quality Microphone Preamp I designed some time ago located HERE

It's been a while since I posted a project because as you (may) know I build up things before I post them so I know they work however I've had bugger all money to buy stripboard, I actually had to de-solder an old project to get enough to prove this one so if anyone can help me out with some stripboard I'd be most grateful!

Paul in the
Lab is here to help
Everyone into electronics
All ways feel free to
Seek my advice
Either using the
Contact button or my email
Lately I am always at the computer because
I am always designing stuff though I did buy a new
Camera recently, I remember the first thing I built was the
Knight rider LED scanner which I only
Added a few days ago, anyway I
Digress, hope you enjoy my
Site

anyway here is the filter

Knight Rider Kitt / Cylon LED Sequencer Stripboard Veroboard Layout

This is a cool little project I've been meaning to do for a long time. One which was so simple I kept putting it off.
Essentially this is a 8Hz (ish) squarewave generator attached to a decade counter - it counts upwards displaying each count on the next LED however the outputs are wired in such a way that instead of just going upwards it goes back downwards. it should be obvious when you look at the schematic how the thing works.

Anyway as the name suggests the LEDS go back and forth like the eye things on Cylons from battlestar galactica or the front panel on the car from knightrider. my older brother drives a taxi so I plan on using this to drive relays to big lamps and attach it to his car when he's next away.

This circuit is very useful outside of replicating old TV show LED things, you can use it to sequence pretty much anything using relays or even digital circuits and you don't have to use the 555 to do it automatically, you can replace that with a push switch circuit to the CD4017 Clock pin (14) and control a pedalboard for example
or maybe even make your house seem haunted by using it to remotely control appliances. I will include a simple Relay Driver below.

 

To use the CD4017 to drive a relay

Mosquito Repellent Stripboard Veroboard Layout

I'm pretty ill at the moment and I didn't want to really get up let alone make a circuit however the reason I am ill is because of bastard mosquitos - you see they bite you and your body reacts to the bites as it would a virus and with an illness the actual feeling of being ill is your body attacking the illness. in most people this reaction lasts a very short time and you don't notice it however with me any illness I get prolonged reactions, I always have which is why I feel really ill right now.
So in order to stop it happening again I thought I would make an electronic mosquito repellent

it mimics the sound the pregnant female mosquito makes which warns others to stay away.

RIP Hans Camenzind

sadly, the inventor of the 555 timer IC passed today

Dual Tracking Power Supply Stripboard Veroboard Layout

another project born of necessity (ie I blew my other one up) This is a 1.5Amp dual polarity power supply (adjustable)

This may look like a waste of stripboard however once you see how big the 1000u caps are you will realize that you need the room.

6 watt desktop amplifier stripboard veroboard layout

I wanted a nice powerful stereo amplifier for studio use, I'm pretty sure this will drive a few pairs of headphones/speakers though I've only tried it with one pair.
this would also be well suited for a nice set of powered monitors for a laptop or any other application.
anyway, I found the TPA1517 from Texas Instruments and it works great.

the powersupply needs to be very clean maybe even external to the unit itself. you'll notice there is a resistor across the terminals of the big capacitor (4700uf) this is a bleed resistor and its purpose is to discharge the capacitor once it is powered off, with the value stated it takes about 3- 4 minutes to discharge the 4700u 40v capacitor. it's not a necessity but it's advised to avoid electric shocks - even the 40 volt cap I used packs a nasty punch.

when you turn it on don't have your headphones over your ears - this is very very loud so the input signal needs to be raised very gradually