This was redrawn from an Australian electronics magazine...
I use this to test with.

Very simple sine wave genarator. The trick in this one, is that harmonic cancellation is used to get a very low distortion sine wave. Output amplitude stability is also very good.

I hope this is of use to others.

What are some of your favorite soldering irons/stations?
Tools, tips?

I'm looking for an inexpensive upgrade to my Weller 40W pencil.
It's been great for through hole boards, and using sockets for ICs,
- but replacement tips seem a little hard to find, and I need something smaller with more kinds of tips to do occasional SMDs.

so this is really only proof of concept at this stage but it's looking like it'll work okay.. I need to tidy up a lot of it but I'm pretty happy with the result so far..

it consists of:
a base (offcut of some decking timber I had)
a flushmount from a light switch
some plastic waterpipe
some dowel
a plastic waterpipe mounting bracket
a piece of thin timber to which the bracket above is screwed
a DC drill with 0.8mm chuck (ex ebay for some kind of spring (yet to get this)
some screws to...

For all those who are making the effects this is very useful tool.
The basic features are:
-measurement input impedance of effects, various preamps and amplifiers
-measuring the output impedance of effects, preamps
-generating sinusoidal signal with variable amplitude
-use of vu instrument meter for measurement, comparison of two signals simultaneously

Audio impedance meter is useful for measuring the input / output
impedance values ​​0-1K Ohm and 0-1M Ohm, generating sine waves
670Hz...

which is the best breadboard for effect pedal experimenting?

hey freestompers,

had a good plough through the Stompbox Building / Stompbox Builder's FAQs & How To's / Electronics Tools threads and couldn't find anything on breadboards. maybe it seems like a too simple thing to ask about, but to the newbie eye there are a few different types and sizes and layouts out there and when you have't used one before it's impossible to make a reasoned decision for or against any. as i only want it to...

Guys, I searched a lot for something like this and it seems nobody did this for dummies. So being one myselff I decided to post something :icon_mrgreen:

First of all you here is the theory behind this:

Here you have the pcb and layout for the circuit noted in the above link

Download and burn. You have to hand pick a resistor that is closest to 2.2M, and with a muti turn pot, dial 2,472 (or 2,47 if your DMM goes off range)
Populate the board.

After that hook up everything as per the...

I realize that different people have different amounts of personal time to dedicate to building pedals. Some people build daily while others do it rarely. Generally speaking, I am wondering when most of you guys decided it was time to get an oscilloscope? How many pedals had you built before deciding it is time to go all in ?

Did you run into a problem that you could only solve by getting one? Did you just want one to be thorough? Did anyone buy one not knowing anything about it and it just...

Howdy,

Specifically for building pedals, is there any reason I should look to the mixed signal oscilloscope vs the digital only? I can get a Rigol DS1102D used for the same price as a DS1102E new but it doesn't come with any of the accessories (logic module, cables, probes) so I'm a bit cautious about getting it if I won't need the extra features. I am interested in getting into tremolos, reverbs, and delays if it makes a difference.

Thanks!

Hi, I have matched some J201 using this article :

it is really simple and fast (so I suggest it... :applause: )

The lower Vgs I measured was 0,22 the higher was 0,74

Question 1 : What is the range for J201 in order to say that these are GOOD / POOR / SO-SO ?
____________________________________________________________________________________

Then I pickup the two extremes FET ( 0,22 and 0,74 )

putting 1K on source I've start biasing.
TRX 0,22 was biased with 15K resistor on drain
while...

Hey, hoping I'm asking this in the right part and one of the numerous helpful experts that visit here might help me out :D

I was very kindly given an old analogue Oscilloscope - a Telequipment/Tektronic from 1978(!)... I got a really big a kick from getting this (a symptom of hanging around here for too long maybe... I've gradually found the tools and understanding have become as interesting to me as the actual things we make with them :D )

I've never used an Oscilloscope and have ordered a...

I'm currently building some distortion circuits, and have a few question about when to use matched pairs of JFETs. I've read in various places about how using matched JFET pairs is beneficial. Usually one reads about these matched pairs in phaser circuits where the JFETs have to turn on and off together and you need them in a similiar range to do so.

First question -
One of the circuits I am building is the internet-known Dr Boogie circuit, where there are discreet gain stages in series....

Hey all,

So I have a few effects on my bench that could really benefit from using a scope to set the trimpots. Specifically, right now I have two delays, and a few modulation effects that I need a scope for.
But I looked into the world of oscilloscopes and suddenly realized, Oh god, I'm way in over my head, I have no idea what to even look for! Can someone please tell me what requirements I should have when shopping, or better yet, recommend me a simple scope? Obviously I'd like to spend as...

Sometimes I either order a powdercoated enclosure or paint an enclosure and need to drill it afterwards. This can present a problem because the jaws of the clamp can mar / mess up the finish, and that's not good. Over the years I've done various things to protect the finish, but the solution I finally ended up with has worked out quite well....

I want to the local craft store (Hobby Lobby, Michaels, etc) and got some sticky-backed sheet foam. Its about $0.80 a sheet, and one sheet will last a...

Hi all,

I was wondering if anyone out there has used computer based oscilloscopes that take in audio from a soundcard, and has an opinion on their shortfalls or could recommend a particular one.

Many thanks,

ff

I'm looking for a 3rd hand type tool.
I've used them before, but forget the exact name of them.
Its similar too the 3rd hand thing but instead of alligator clips, it has something that looks like this:

The hole in the piece there is where it slides over the shaft that the alligator clip assembly normally goes on.
It uses 2 of those pieces.
They both slide along the shaft so you can set it to whatever size the PCB is, and the groove in them is where the PCB goes.

Thanks

(Now lets see how...

I couldn't find any vero layouts on the interwebs for R.G. Keen's JFET matcher, so i went ahead and made one. I didn't have any single op-amps, so i made a layout that uses half of a dual op-amp.

Problem is, it's not working, and i've been going over the layout like crazy for the last hour. I just can't see what i've done wrong.
Everytime i stick a JFET in there, the DMM readuot drops from V+ to Vmid (9.44V - 4.87V). I find it kind of hard to believe that all of my 2N5457's have a vgs of 4.87V...

Being a total noob at this, I'm having trouble reading the the schematic for the JFET Matcher. I get that the +ive goes to pin 8 and the -ive into pin 4. Is the pin to the right for pin 1 (or 7), the pin on bottom to pin 3 (or 5) and the pin on top to pin 2 (or 6)?

thanks in advance!

so i have 2 audio transformers

how can i determine their values? can i use them as substitute for 42MT018

thanks

Ive been drilling my enclosures with a cordless drill and a Uni-bit from day one. I think its time to upgrade. I don't have a lot of space in my home so this is perfect for my small batch production. Just thought I would share this new discovery with everyone.

Has anyone had any experience, with this:

mind you, it says non-toxic but poisonous :scratch:

ugh, pls forgive me, just saw that there is a section 'stuff seen for sale'. sorry for misplacing the msg. :oops:

Anyone have ideas for small drill presses?

I live in Brooklyn, NY, and dont have a shop/garage in which to keep a full sized drill press. Im thinking that there has to be something available in more like a bench-top size that I could put out of the way in a closet when I dont need it. Ive got a dremel, and I know they have the drill press stand, but all that would get me is a press for pilot holes, and i'd still have to use the hand drill for unibit stuff.

DSC00672.JPG
I like to scavenge some old (or new) stuff and reuse parts. In the picture above, you can see what I recently found inside a Philips disc/cassete/radio player and I think it can be a nice power supply and with a little tweek, just can be boxed.
Got 10 ACV in the transformer output and 13.45 DCV in the rectfication board output, so we got voltage enough, but I didn't know how many current I get.
Judging by eye, seems like 1A transformer, but I want to be sure.
How can I get a...

I'm getting damn tired of stripping wires in stompbox builds. Shit takes too long and its just no fun. So i'm thinking about getting a set of automatic wire strippers. My problem is that there are a lot out there, and very few of them will do small gauge wire.

So....anyone have any recommendations for an auto-stripper that will work with 24-gauge wire? maybe 22-gauge?