Quantcast
Channel: Paul In The Lab

RIAA Phono Preamp Stripboard Layout

$
0
0

I'll start this off by saying I'm not that keen on record players but last night I dusted off my old Garrard turntable and promptly realized my amplifier doesn't have a phono input which meant no RIAA de-emphasis equalization. Or in other words my records would sound like shit.
So I opened up eBay to buy one - then I remembered that I know how to make things so that's what I did.

I didn't do it for the site specifically but I thought I should share it with you people in case you ever have this problem. I also used top quality parts such as the OPA2134 op-amp - this is the perfect type of application for this part - it is an op-amp designed for the full audio range.

as a side note - read the product reviews for this IC on the texas instruments page - some of them are hilarious - here is one quote "Replace those TLO72 with these and the difference is huge! (extended low end, smooth mid-range airy top end)"

people really like to talk a lot of shite about things that are not there! - this is a very low noise op-amp optimized for the audio frequency range. if it made things sound "extended, smooth and airy" then it would be a poorly designed product. 

Anyway - if you don't want to spend a load of money on a OPA2134 or you want to try it with a cheaper op-amp any audio dual op-amp will do. I tested mine with a RC4558 (cause it was nearer than the OPA2134)

it is powered by a 20 volt supply, though I'm sure it will work at lower voltages.







Hifi OPA2134 General Purpose Preamp Stripboard Veroboard Layout

$
0
0

in my last post I made a RIAA preamp for my turntable and I decided I wanted to make a general purpose hifi preamp for iPods, PCs, and whatever else you need to plug into your HiFi

so here it is - based on the OPA2134 opamp (again)

although I haven't tried it for this, I'm sure it'll work well as a instrument preamp too





Ellas Stylophone Stripboard Layout

$
0
0

I have a 2 year old niece called Ella and I wanted to make her something - so I thought I would make her a Stylophone.

NB: there were a couple of errors due to me somehow pressing the "up" button in "DIY layout editor" after I had built this but before I had rendered the image. these errors have been corrected

the original error was; the "tuning board" was listed as being connect to pin8 of IC2 - however it should be connected to pin 7 of IC2
I also missed out "R4" in the schematic (cause I drew the schematic after building it)







Me and Ella

Green Wizard Guitar Overdrive Distortion Stripboard Layout

$
0
0

I've been working on this for quite some time. I've always wanted to design my own distortion pedal and finally I have.
I used 2 main parts for this - one is a TL081 general purpose J-FET op-amp and the other is a more special LT1037 op-amp - I chose this for the high-end clarity and low end solidness... haha not really (I don't believe that crap) no, I chose this because it is a very fast and low noise op-amp. it also has input current limiting diodes which affect the type of distortion this pedal gives you. it is also quite low power (in the order of about 2.5 mA)

I did a quick video demonstrating how it sounds which I will attach below.

the name comes from my favourite cartoon growing up - "the flight of dragons"  hopefully I will make 3 more of my own stompboxes for the other 3 wizards in that film.

NB - I put germanium diodes in this and it improved it drastically 







Mains Failure Alarm Stripboard Layout

$
0
0

I have a fish tank and in it - lives many tropical fish - however the other day the plug socket switch the heater was plugged into somehow got knocked off. luckily I noticed the heaters light wasn't on and the water temp hadn't dropped so the fish were safe however I wanted to make a little device to warn me if the mains got turned off somehow without having to wire it to the mains directly.

So here we have a little device that starts beeping if the mains is turned off - obviously this is battery powered but the battery should last a long time because it's very low current draw.

the trim pot on the board adjusts the sensitivity of the antenna which is just a piece of wire than you wrap around the cable you want to monitor.


Ruby Amplifier Stripboard Layout

Simple Dual LED Battery Monitor stripboard layout

$
0
0

I got some 3 pin dual LEDs and I thought a good use for them is as little 9v battery status monitors for my guitar pedals. so I came up with this quick circuit that fades from green to red as the battery voltage drops (as shown in the video)

it's a good little mod circuit for any project you want to build that uses a 9 volt battery (or existing stuff you own)




Vox 1901 Distortion Stripboard Layout

$
0
0

Well - it's been a while, I'm in the late stages of moving house and I also dislocated my knee quite badly - I had to shift it back into place myself cause where I fell trapped me.
Anyway all that has prevented me from doing any new projects until now. things are still hectic and I can't walk so it may make things a little sporadic.

I thought I would do another guitar distortion cause I am recording an album at the moment and I wanted to try out the Vox 1901 Distortion so I did and here it is.




Guitar FX Switching Diagrams

$
0
0

I keep getting requests to do some diagrams on how to wire up guitar FX circuits so I've done the ones I use.


Obsidian Overdrive Stripboard Veroboard Layout

$
0
0
This is quite a brutal high gain overdrive by Joe Davisson based on another pedal called the massacre.
it's a very mod friendly circuit - some good places to start are changing some of the capacitors (C1, C6 and C8) for example.
I actually knocked the layout up in 15 minutes but because I have been in so much pain due to a dislocated knee - it took me 2 sittings to actually build it (the valium kicked in 30 minutes into the first half)
anyway it sounds immense
if you have any issues with switching refer to FX Switching

REMEMBER THIS IS A POSITIVE GROUND CIRCUIT - it needs it's own isolated supply eg a battery
otherwise you're going to have a bad time



Electronic 3 Band Equaliser Stripboard Veroboard Layout

$
0
0

There are lots of circuits on the net for 3 band EQs but I wanted something a bit more powerful than the usual 20+dB/20-dB things on offer so I went on eBay and bought some grey market MC3340P attenuators from china and made this thing.

I made mine for a send/return loop in a very simple valve amp I have but it's perfectly capable for hi fi audio.

it's worth noting that this works very well if you turn the knobs slowly because they aren't actually in the audio chain - they are part of the voltage control architecture of the chip

It's also worth noting that it will work on 9 volts if you want to make it into a guitar pedal.



Boss OD-1 Original RC3403 Quad Op-amp Stripboard Veroboard layout

$
0
0

This is something I've wanted to re-visit for a while, I was never happy with my original layout - you couldn't use the proper op-amp in it and it was a bit crappy looking too.

I have added 2 parts to this build, neither affect the sound - they protect the circuit from the wrong polarity supplies which is necessary if you use the original RC3403 op-amp because it costs a fortune.

you can of course use a jellybean quad op-amp like a TL074 or LM324




 

Blue Wizard Overdrive / Distortion Stripboard Veroboard Layout

$
0
0

This is the Blue Wizard - part of my "wizard" design series (Green Wizard HERE) - this is a very harmonic rich overdrive/distortion that uses 2 BC182L transistors (cause I have a load of them) - this is the same transistor used in the Brian May treble booster HERE

it has a bias pot onboard and I find it's best to adjust it till it sounds good to you.

anyway - below is a quick sound sample - the 1st bit is the gain all the way up and the 2nd bit is the gain half way up.






ADSR Envelope Shaper Stripboard Veroboard Layout

$
0
0

I've been a bit busy recently so I thought I'd scan this interesting looking project in from a magazine from the 70's





Bi-Polar (BJT) Through Hole Transistor Package Types

$
0
0

I found this cool little info thing from the 1970's so I though I would share it:



2 Watt Transistor Guitar Amplifier Stripboard Veroboard Layout

$
0
0

When I was young (about 9 or 10) - this is one of the first "big" projects I successfully completed and still actually use to this day so I thought I would build a new one for everyone to enjoy.




Proper Op Amp Termination

$
0
0

I've been designing a sampler recently (sorry, there won't be a stripboard for that, it's way too complicated!) however I was using a quad opamp for a part of it but I only needed 3 of the op-amps which gave me the idea to post a little tutorial on the correct way to terminate unused op-amps and a brief explanation why (I'm sure there are very in depth youtube videos/documents elsewhere)

the extremely brief reason to terminate a op-amp correctly is that it may draw extra current or it will pick up noise (or both)




Simple Audio Mixer Stripboard Layout

$
0
0

this is a quick project I made for another project I'm working on but I'm sure people will have uses for this so here you go.

it's also worth noting (as I have before) the purpose of C1 is to limit the bandwidth of the Op-Amp - in this case I've used a value to stop any hiss however you can experiment with the values and make a low pass filter - the higher you go the more it cuts off.




Quick And Dirty Laser Driver Stripboard Layout

$
0
0

This was just a quick little circuit I built to test all the salvaged CD/DVD lasers I have.
essentially it is a adjustable constant current power supply.

the Vin is 7.2 volts.


Frequency Meter Stripboard Layout

$
0
0

I built this as a rough frequency meter to make sure a bunch of oscillators were oscillating in the right ballpark frequency.
it uses the lovely 555 timer IC.

it responds best to squarewave signals (maybe triangle too, I forgot to test it with triangle waves)



Very Accurate 10volt and 5volt Reference For Testing Multimeters etc. Stripboard Layout

$
0
0

I thought this would be a good project to keep around to see if my digital multimeter has drifted out of calibration.

I power it from a normal bench power supply but it would probably be better if you used 2 9v batteries in series.

The LED on it displays when over 100mA is being drawn from it - basically if the LED is lit disconnect it or things will be getting very hot!

I tested it in free air with open windows over 2 hours and it was very stable so I can rely on it.

Linear Tech do a few different drop references for this IC
the 2 I've tried are the 10 volt reference and the 5 volt reference
the part numbers are
10 volt reference; LT1021BCN8-10
5 volt reference; LT1021CCN8-5



it stayed at 10.0006 for over 2 hours - the least significant digit moved around but that's 10's of uVolts!


Piss Off batteriser

$
0
0

when doing the admin part of this site,nothing infuriates me more than having a company trying to advertise their snakeoil products in the comments section.
I often get comments where someone has copied a bit of the text from my blog post and then shoved a link to some crappy product after it and usually I just delete it but given the fact that Batteriser has been so underhanded and dishonest about everything they do and claim - I thought I would call this one out.

Dave Jones from the EEVblog has debunked their product in just about every way imaginable and they've done some hilarious reply videos to him where some "engineer" is sat at a table with an oscilloscope hooked up to its own 1Khz reference/cal signal (with very badly compensated probes), some wires and boards and a suspiciously new and cheap looking soldering iron; explaining why Dave is wrong. then, when that failed they just paid people to downvote his videos.

so Batteriser, do not advertise your shitty, useless products on my site.



Daves Videos

Electret Microphone Preamp Stripboard Layout

$
0
0

someone asked me to do this, so I did. it's a useful little circuit to power those little electret microphones.



Maxon Treble Booster Stripboard Layout

$
0
0

I came across this interesting little thing so I thought I would make a clone of it.
it's a maxon treble booster.

they also did one called the power booster and as far as I can see the only differences between that and this is that the power booster has 2 470n capacitors in place of the 2.2n capacitors.





Red Wizard Fuzz Stripboard Layout

$
0
0

this is the 3rd guitar effect in the "wizard" collection.
As anyone who has followed this site for long enough will know, I always make my pedals very minimal when it comes to controls but if anyone does add to this circuit I'd love to see what you've done.

anyway, enjoy.