Things With Strings

It's coming up to Christmas, and what to buy for your daughters boyfriend? Hmm, how about making him a pedal for his guitar. After much deliberation I decided on Tim Escobedo's Duende (MOSFET version) and drew up a super-compact perfboard layout... I went straight into soldering without breadboarding, as the circuit is pretty simple, and luckily it worked straight away. Here's a picture after adding all the components to the board. And here's a shot of the completed unit In use, I found that I needed the volume control at about 1 o'clock before I could hear any difference, and I was expecting to hear something a bit earlier on the dial, but once above 1 o-clock, there is plenty of volume to be had. Switching the device on does brighten the signal somewhat even at unity gain, and the device is very quiet in operation, No hiss, hum or buzz. I wish I'd had a girlfriend whose dad made pedals when I was his age!

After the success of Pete's Bazz Fuss  I figured it was my own turn. I've only ever used stripboard in the past, but wanted to have a go at building a circuit on perfboard instead, so wanted to choose something relatively simple for a first go. The circuit I chose was the EHX™Muff Fuzz™ which despite it's name os more of an overdrive than a fuzz type effect. I drew up my own perfboard layout as below, taking care to make sure the components could be connected easily when soldering. Soldering up was relatively painless, and I was quite please with the neatness. You can see from the pic below that it is a mirror image of the layout above. I used 2N5088's for the transistors and 1N60P for the diodes. The picture below shows the component side of the board prior to shortening the transistor legs.  It worked pretty much straight away to my relief, and sounded OK, so I boxed it up in a 1590A sized box (always a painful process) and here is the f...

It's been ages since I built an effects pedal, so to get my soldering chops back up to speed, I decided I'd build a simple fuzz pedal for my long-time friend Pete as a surprise present for his impending birthday. The circuit I chose was the Bazz Fuss (yes that's the correct name)  which you can read about here if you care to. I went for the basic v1.0 of the circuit and used a 2N3904 for the transistor, and boxed everything in a 1590A sized enclosure. Despite a number of stupid mistakes that I had to rectify, I got it all done and boxed within a day, complete with lo-fi graphics. Here's a gut-shot. gut-shot And here is the finished item. lo-fi graphic It sounded OK when I played it although it needed the volume knob maxxed out to get the best out of it. Maybe a higher gain transistor would have been better still. I'm pretty sure Pete will like it though.

Buoyed by the success of last month's " Chafer Drive ", I've been busy drawing up layouts for a few more small effects that I want to build, and first up is a tribute to the " Shin Ei Companion Fuzz FY-2 ". This was a Japanese fuzz pedal made in the 1970's and is generally well-regarded in the DIY effects community for it's classic fuzz tones. The original came in a large wedge shaped box, but my plan was to squeeze it into a Hammond 1590A  just as I did with the " Chafer Drive ". This was undoubtedly going to be more challenging, since (a) the circuit is larger, and (b) it has two control knobs as opposed to one. I had some standard 25 x 9 stripboard  which I thought would be ideal for this purpose, so I challenged myself to layout the circuit with that in mind. The original circuit use some obscure  2SC536 transistors (Hfe 160-560) that were no longer manufactured,  but I had a whole bunch of 2SC1685  (Hfe 160-460) transistors that I...

Still on holiday from work, but my back is on the mend thankfully. I've been tinkering with another pedal (more to come) and it's a bit of a strange one. It has an unusual switching mechanism which means that it's not bypassed in the usual way. I'd heard others report that this effect suffered volume loss when engaged, but my breadboarded circuit suffers from volume loss when in the signal path, engaged or otherwise. In fact, the volume difference between on/off states is negligible in my case. I wanted to try a few things, and one was whether buffering the effect would make any difference. So I conjured up an idea to make a plug-able buffer that I could use for this purpose now and in the future when breadboarding circuits. The circuit I used was the bi-polar transistor buffer circuit  described in the link, and here is what my finished item looked like. plug-in buffer In the end, this particular circuit didn't benefit from the addition of a buffer, but...

Today I was on holiday from work, but I'd also done some thing to my back that meant once I sat down, I was in danger of not being able to stand up again, and my intentions to go out on my bike and put some miles in were well and truly scuppered. So to keep myself active, and in a standing position, I decided to prepare a couple of boxes in advance. These were  1590A  size boxes and I was preparing them for some effect that will have a single control. First I printed out templates which I downloaded from madbeanpedals.com  and taped these to the boxes. Then I used a centre-punch to mark the location of each hole I wanted to drill in order to guide the drill. enclosures with drill templates and tools In the picture above, you can see the two enclosures with drilling templates attached, together with a centre-punch, a couple of step drill-bits and a 3mm drill-bit for the LED. And here is what a box looks like once it's been centre-punched. enclosure w...

Background I was talking to my brother-in-law last December and mentioned that I was hoping to re-ignite my electronics hobby, mainly with the intention of building myself some guitar effect pedals. A month later, my brother and sister-in-law kindly gave me an Amazon gift card for my birthday (always appreciated), so I had the idea that come his birthday, I would repay the gift with a boutique, hand-made effect pedal. And so the story of the "Chafer Drive" begins. I thought a simple overdrive (mild distortion) with a single control knob fitted into the smallest possible enclosure would be appropriate, and it would be named the "Chafer Drive" because that, coincidentally, is his surname. The name has a triple meaning though, since a Chafer is a variety of beetle, and there is a party-game called a Beetle Drive , so we have Chafer - Beetle - Over - Drive, get it? Never mind! I though I'd also document the whole build process too, so he (any anyone else who...