Thought I could do it...

[Noplasticrobots]

I'm trying to build the Electra distortion found here:

http://www.geocities.com/j4_student/electra.gif

I'm building point to point, or rather some variation of a point to point process. I got the circuit together based on the schematic AND the PCB layout:

http://www.geocities.com/j4_student/electra2.gif

The circuit desn't work. I flip the switch on and I get a loud hum, so something is turning on, it's just not coming through.

One thing I know I did wrong was I accidentally bought DPDT center off switch. I tried wiring it the same way as the PCB layout shows because all DPDT have the center terminals in common (or so I've read). I corrected a couple mistakes and I still get a loud hum when the switch is flipped. I'm kinda confused on where the wires on the in and out jacks go, because it's not on the schematic and the PCB picture is very vague.

Instead of wiring point to point, should I trim the leads short and connect everything with wires? I'm using a Radio Shack PC board that does not have busses. If I do connect everything with wires, what about points where three connections come together as in the Collector of the transistor, R2, and C2? ugh, I thought this was gonna be easy...I've been reading websites for a month now and even read Electronics for Dummies. I understand the schematic, but actually placing the parts is giving me trouble. Any help is appreciated. Thanks!

[Peter Snowberg]

Welcome to the forum.

Don't worry, you'll get it running. One of the wonderful things about this place is that regardless of skill level, we're all here to help each other. We all started at the same place.... we've ALL been there.

Do you have a DMM? If so, please measure the voltage between the battery ground and the three legs of the transistor. That should shed some light on the problem.

When you see more than two components connecting together on the schematic, all you need to do is to make sure they're all connected in the real world. For a circuit like that it doesn't matter what the order of connection is, just as long as you have wire connecting all the required points together.

The second picture does a pretty good job of explaining where the leads go. The trick is getting familiar enough that it all makes sense on first glance.

Let's take it step by step and I'm sure you'll have a working circuit before long. Is there any way you can post pictures of what you have so far? That would be nice, but the transistor voltages will be of the most benefit in diagnosing.

[Joe]

The jack pictures don't make sense. Here's how to hook them up, looking from the top-down with solder tabs at the bottom:

stereo jack:
1. battery
2. ground
3. signal

mono jack:
1. signal
2. ground

[Eric H]

The jack pictures don't make sense.

They do if you look closely enough --they should be a little larger.

Here's how to hook them up, looking from the top-down with solder tabs at the bottom:

stereo jack:
1. battery
2. ground
3. signal

mono jack:
1. signal
2. ground

Top of what?  is the jack pointing right or left?. What do the numbers correspond to?
I'm not giving you a hard time, but suggesting that you give it more thought when you are improving  existing instructions. Imagine it's the first time you ever looked at a jack.

-Eric

[jmusser]

Look at any of my EZ Build drawings on GGG, and they will show you how the jacks are physically wired. I know, that it was something that threw me off for awhile, because the schematics assume you know how the bypass switch and jacks are wired, and newbys don't. I sure didn't! If you don't know what your tip, ring and sleeve are, follow the solder lug around the inside of the insulating wafers. On a stero jack, the tip will be the bent spring farthest away from the back of the 1/4" plug in hole. The ring, is the next one in, and the sleeve surrounds the hole, and goes to ground. It's easy to tell if you plug your guitar cord into it. Most people use the stereo jack on the input, so that once the guitar plug is in, you have powered up the pedal, by having the negative of the battery snap to the ring lug. The output and input off the board, always go to the middle of the stomp switch. Think of the middle of the stomp switch as your pivot point, if this was a simple toggle switch, since it works the same way. If you have the bypass wire across the bottom two lugs, when you pivot the toggle up, you have to take the input and output, through the bypass wire. Across the top, you're going off to the input and out put jack tips. Use the line down the middle of switch as your devider, because you really have two SPDT switches in one housing. The 3PDT that Aron sells has 3 SPDT switches in it, so you'll have a separate switch for the LED to get powered up at the same time your effect does. On the GGG site, there is also a diagram on how to wire in a DC jack along with the battery. I hope that helps.

[Noplasticrobots]

Thanks for all the great replies. I can upload some photos later, but I'll tell you, the board doesn't look too clean. I don't have a DMM yet, I'll hopefully be picking one up today. I'll post later with at least some photos. Thanks again!

Edit:
Would a meter like this work ok for what I'm doing?
http://tinyurl.com/288gu
Or would a meter with auto ranging and diode checking be more useful?
http://tinyurl.com/y2bd

[Peter Snowberg]

When it comes to tools, I always feel it's better to spend in the beginning because you'll usually get more out of the tool in the end.

I would go for the more expensive of those two. If you look at the resistance ranges each one measures, you'll see the more expensive meter goes to 20 megs while the cheaper one only goes to 2 megs. You won't have to measure many resistors in that range, but the capacity shows that the more expensive meter probably has a much higher input impedance which is a very good thing.

If you're going to build circuits with transistors in them, it's also VERY nice to have a transistor checker, or hFE test function. As a generality, I avoid any meter that does not have a diode test.

If you spend more than $50 at http://www.circuitspecialists.com/ , they usually have a give-away meter you can get free by entering a code word at checkout. (right now that code is "PR-TECHMETER")

They are a great place for soldering equipment and little parts like film capacitors and resistors and the free meter includes a transistor test function.

My advice would be to spend $50 because it's really going to be worth it in the long run. Example: get a cheap soldering station like the CSI-STATION1A for $34.95, some 63/37 solder (part RH63-1) for $8.18,  spend another $7 on misc components, and now you have the meter along with a soldering setup that will make your life MUCH easier EVERY time you go to solder something.

To paraphrase B. Tremblay of http://www.runoffgroove.com/ , soldering with a temperature controlled iron and 63/37 solder is like waving a magic wand. 

[Connoisseur of Distortion]

after one year to this day... i use a ratshack iron. i like my kester solder, though 

[Noplasticrobots]

Well, I went with the more expensive of the two DMM's I listed. I know it doesn't have the transistor check terminals but I think it'll work for now.

Here's some photos of what I have so far.






But before I get scolded for a horrible point to point job, let me run a plan by anyone who's reading.

I'd like to cut all the component leads shorter (except for the transistor) and desolder them from the board and redo this circuit on my breadboard. But since you can't connect stranded wire to it I went to RS today, and got some 20 gauge solid core wire so I can wire external components into the breadboard. Is this a good idea? That way I can troubleshoot the circuit and attach pots and jacks to make sure everything sounds good before soldering. I also bought a "PC style" board for soldering that has busses on it so I won't have to add so many wires, is that a correct assumption? Also the transfer from breadboard to PC board will be easier.

In my circuit you'll also notice that I have one more resistor than called for because I couldn't find a 2.2M resistor so I used two 1M resistors in series.

Ok, so that's where I stand for now. I used an alligator clip as a makeshift heatsink when soldering the transistor so it wouldn't overheat, so it should be safe to reuse...I assume?

[Noplasticrobots]

I used my DMM to check for continuity in the circuit and I got no buzz, so I assume everything is in order. This may seem like a dumb question, but when you ground connections, do they all have to be touching? I though they all just had to reference the same voltage, so I wired all my grounds to individual holes in the socket board...

[Marcos - Munky]

There's a error in this layout. The error is in the output part of the switch. See these two green wires? Just reverse them.

[Noplasticrobots]

I switched the green wires and still got nothing. When I switch it on, you can hear it "turn on", and if you hit the strings hard enough you can almost hear what sounds like a faint fuzz, but it's next to nothing. Like I said, I accidentally bought a DPDT on-on switch, which the schematic does not call for, so that could still be the problem. As far as I can tell, my diodes are line up correctly...I'll keep troubleshooting.

[johngreene]

When I look at your pictures I see 5 wires all coming into the board in a row near the edge and they don't seem to be connected together or to anything else for that matter. Are these your ground wires? They will need to be all connected together.

--john

[Noplasticrobots]

Yeah, those are my ground wires...well they were my ground wires. I ditched that board and moved everything to a breadboard to make sure I'm doing everything right...but I still can't get it to work.
I took everything that's off board and I soldered solid core wire to the terminals and mounted into the breadboard. When I have off board connections to make, I just plug the two wires into a strip on the breadboard.

I'm wondering if I should post a picture of my breadboarded circuit, see if there is any errors in it, then post a pic of the connections to off board components and see if they're right.

By the way, no one's commented on my use of the wrong switch...would you wire an On/Off DPDT the same as a On/On DPDT?

[johngreene]

Not sure by what you mean when you say ON/OFF DPDT or ON/ON DPDT. Double throw usually implies the center pin is connected to one of the other 2 pins for that pole. If what you have is a ON-OFF-ON, or center off switch, it will work but you would not want to ever leave it in the center position. Is it a toggle switch?

--john

[Transmogrifox]

I used my DMM to check for continuity in the circuit and I got no buzz, so I assume everything is in order. This may seem like a dumb question, but when you ground connections, do they all have to be touching? I though they all just had to reference the same voltage, so I wired all my grounds to individual holes in the socket board...

This is a very important question.  I'm not entirely sure what you're doing for grounding, but every ground connection should be touching.  In other words there should be some kind of conductive path to the negative battery terminal in this circuit.  Here's a good way to test your grounds:

Now that you have a meter, do a continuity test and verify that each point on the circuit that is supposed to be connected to ground has a connection to the battery negative.  Leave one lead of the DMM on the battery negative connection, then probe the emitter of the transistor, the ground side of the diodes, the grounded side of the pots, the sleeve (and ring) of the input and output jacks (with some sort of guitar cable plugged in) and verify that they all show less than one ohm to the battery negative.

I have another idea that will help since you're using your breadboard:  Forget about the switch.  Just hardwire the ring of your input jack into the breadboard to the input capacitor on the circuit, likewise, the output jack ring to the output lug of the pot.  Next, ground the sleeve connections to the negative power supply strip on the breadboard.  Furthermore, instead of trying the "power on" thing with the battery, just connect the battery's negative terminal to the breadboard negative strip, and the positive to the breadboard positive strip.  If you have an LED, put it in series with a 4.7k resistor between the power supply traces to make sure the battery polarity is correctly connected.  (the LED will let you know it's powered up right).  Anode goes to power supply positive (usually long lead), cathode to 4.7k resistor, other side of 4.7k resistor to ground (batt neg).

From that, wire up your circuit per the schematic, plug it in and see if it works.  It if doesn't, play with it in that form until it does.  After you have it working, then add the switch, see if it works, then wire the input stereo jack to power up when the cable is plugged in.  When that works, copy it onto your perfboard and stick it in a box.

I applaud you for picking a simple circuit for your first.  Imagine trying this troubleshooting task with a tubescreamer or Mutron!  You will get this to work.  The best part about it is that there is something important you're missing in what you have gathered in your reading, and when you figure it out, you will have learned something that will make the next circuit that much easier.

Take it easy, I hope it works.

[petemoore]

  One lead 'black' of my meter is definitely a clip ended affair.
  I can always clip a conductive shaft in for probe use, and routinely check for ground from battery negative supply [on Neg Gnd circuits] by clipping DMM Black to case or Gnd on a jack or..Gnd, then check all Gnd's.
  Battery clip + is easier to clip on to, then I check all the V+'s from there.
  I end up with a ground wire offboard, or lead that's easy to clip or touch to [like the long end of a standing up resistor], right near the bottom of the board.

[Noplasticrobots]

After a couple hours of reworking the circuit...

I expanded it over the whole breadboard so I can really see what's going on. I did a continuity check and the problem seems to arrive at my diodes. I flipped them, I reversed a couple wires, but no matter what I do, I short at the diodes. They seem to be fine when measured with the diode check, so I don't see what's going on. Here's a picture of just the circuit on the breadboard. Top row (X) is positive, bottom row (Y) is negative/ground. Does everything look correct?

(I've got one electrolytic and one ceramic cap because one of my electrolytics had very short leads...they're the same value and when I solder this board I'll add the electrolytic)

[johngreene]

This isn't wired up correctly. You have the 2.2Meg (1Megs in series) connected between the base and emitter through the .1uF capacitor. The red wire comnig from the base of the transistor should be connected to the same column as the little red jumper between the 1M resistor and the ceramic cap. The other side of the ceramic cap is then your input.

Also, it is usually very helpful if you arrange the components on your bedboard in as close to the order they are shown on the schematic. Makes it a lot easier to follow. You have the input on the far left going to the transistor on the far right coming back to the diodes in the middle.

Hope this helps,

--john

[Noplasticrobots]

Thanks for the help, I now see where I made my mistake connecting the jumpers. I changed them but I'm still shorting at the ground end of the diodes. I can't tell what's wrong!

Just to be on the safe side, here's the numbers I get when testing the diodes by connecting the negative test lead to the cathode: 0.541v

and positive to cathode:0.535v

I'm only getting .2 Ω at the diodes.

Do those numbers look right? I know this is kind of a dumb question, but do my grounds connect back to the negative strip in the breadboard? Also, I'm just testing the circuit without any offboard componenets connected, is this ok?