You know something, the first pedal I ever built was a rangemaster. Since then (2 years ago), I've built about 3 others for friends, a BYOC tribooster, and many more complicated pedals. I have been trying to build a new rangmeaster, and for the life of me I cannot get the thing to work! I have tried making three new boards to put in the pedal and each one same problem: no sound when activated! I cant believe it! Defeated by a single stage booster! Here's what I've done:
Shorted input to output on 3PDT to check if it was busted 3PDT, worked fine
Checked continuity of all connections, all checked out fine.
New CV7112, still not working
tried new 10kA pot, still not working.
Checked to make sure all resistors and caps are correct value and in correct place, still not working.
Continuity check to make sure that components were not touching where they shouldnt, checked out ok.
I've rebuilt a new board 4 times. Switch checks out good. New pot. Getting DC voltages at base/collector of the Ge transistor. Socketed Ge transistor so there'd be no heat damage. I'm pulling my hair out and I can't believe it...
What havent I checked?????????????
Mis-wired jack?
Orange Squeezer did the same thing to me. I finally sat it aside, came back a couple years later and got it together. I can't help you, but I feel you pain. You'll get it going! Mine turned out to be a bit of flux or something causing a short. I went between all the traces with a pick and finally got it working. Good luck!
Battery connected? ;D
I`m having a similar experience with a Kay Tremolo at the moment. It`s on the breadboard and I`ve checked it countless times. It all seems correct but still no Trem. It doesn`t matter how many times you check to make sure everything is connected right, the simple fact that it doesn`t work tells you straight that you`ve done something wrong.
Miswired jack is a good one.
Misoriented Transistors? Another classic.
As you`ve built this circuit successfully in the past I have a feeling the solution may be one of those head slap moments. Sometimes best to leave it alone for a bit and come back with a fresh perspective. That`s what I`m going to do anyway. Good luck.
See, I did leave it alone... for months. I'm back again with the same problem!
Miswired jack isn't the case, I checked by connecting a wire from the "in to circuit" lug on the 3PDT to the "out from circuit" and sound came out in both situations.
Already tried flipping the Ge transistor around, same problem.
Went through it with a toothpick already to remove excess flux, still doesn't work.
Something is going on after the input cap and before the output cap. I get signal after the input cap if I short to the output, and if I short the input to right before the output cap I get signal. And when I turn the boost pot, I hear the typical rangemaster muffled crackle sound from the DC voltage changing. Could it really be a faulty transistor? I tried a spare NPN Ge I found in my university's stock room and still nothing though... I measured all resistors prior to installing them on the board to be sure that they were correct value. Traced the circuit multiple times to be sure I wasn't doing anything stupid... ahh!!!!!!!!!!!! I just want my rangemaster into my AC30 already!
Its nuts...
Have you tried an audio probe?
I know exacly what u feel!
My freaking millenium bypass with 5 parts DOESN'T WORK! Agghhh!
It's nuts indeed!
I had a Green Ringer stump me for a month before I figured it out. There was cold solder joints and I had some transitors in backwards. More than one problem can really make it hard.
After making an audio probe it doesn't take me as long to troubleshoot projects now.
Hard is when u think there is 2 problems and u solve the two problems, but actually there was only one and the other one that u think was u fixed becomes the problem, and you keep wondering MAN WTF IS GOING ON, I FIXED ALL THE PROBLEMS! Then you stop, look at the papers, look at the circuit, think about it a little bit, punch your own face and say:STUPID Bastard!!
+1, the audio probe bails ya out every time!
I build everything with hard-wired in/out jacks, leads for + and - battery. Test it up, make sure the pots are oriented correctly for what they do, etc. THEN I connect the switch, power and LED stuff and box it. If it doesn't work after that, I know right where the problem lies!!
It's ALWAYS some small thing overlooked....pinouts, backwards electro caps, blown parts, a missing ground or power connection...or the ubiquitous, oft-maligned solder bridge....
Doesn't the Rangemaster use a PNP transistor, and positive ground? You said you swaped the NPN transistor........
Oops! I think he found the problem! ::)
Quote from: Shakal on August 29, 2007, 06:27:02 PM
Hard is when u think there is 2 problems and u solve the two problems, but actually there was only one and the other one that u think was u fixed becomes the problem, and you keep wondering MAN WTF IS GOING ON, I FIXED ALL THE PROBLEMS! Then you stop, look at the papers, look at the circuit, think about it a little bit, punch your own face and say:STUPID Bastard!!
That's exactly why the transistors were backwards. I reversed some before I figured out the cold solder problem. When I found the solder joint and it didn't work I got a little discouraged and put it away for a week or two. Then someone (I think petemoore) suggested to check transistor orientation and BAM it started workiing.
I'll add a nod for the audio probe. I've used mine to find problems like that and you'll find it in a heartbeat. Also double check that you have flipped the appropriate parts for it to be an NPN circuit (electrolytic caps) if that is how you did it.
I thought I'd bump this thread since I'm having the exact same problem. No sound except the pot crackling a bit when the pedal is on... maybe Joelap figured out what was wrong.
I'm using this layout, and I switched the electro caps around to work with my 1Spot PS.
(http://img263.imageshack.us/img263/5750/sdfzl9.gif) (http://imageshack.us)
I checked all components placement/orientation, wiring, checked value of the resistors before soldering them in, continuity, and I tried different Ge transistors.
Here are my voltages after I set the trimmer to 7.2v:
E 7.24v
B 7.1v
C 7.2v
Something tells me that the V's shouldn't be that close together.
Any ideas??
hehe... actually, no I still have yet to solve it. Since then I've built two pedals based on the CD4049UBE, both designing my own layout on perf with board mounted pots and both worked FIRST TIME. Damn you, single stage booster. And yes, I did use an NPN, but made the circuit negative ground. All is well in that camp. Out of curiousity, I breadboarded up a rangemaster circuit using the same transistor I had to check to see if it was the transistor. It worked beautifully. ??? It's gotta be in the soldering somewhere. I must be making the same mistake over and over... I'm going to design a new perf layout rather than use the same one I've been using all along... hopefully I'll right the wrong there.
A audio probe is a good idea. I got one last week... Now I'll get into a 30 year Hi-Fi amplifier that has one of its channel not working. Wish me luck.
man, i've been having this problem with a nyquist aliaser. i built one and it worked perfectly after i changed out the opamp but the next one has been unable to perform. i tried all the usual debugging stuff, including swapping fets, opamp, battery, etc, etc, etc...i built a new circuit as well and still no go! arggggh especially difficult to debug because the audio portion works fine (meaning an audio probe is useless...) - it's the s/h oscillator portion that's not doing its job....any tips on debugging that side?
Wrong polarity capacitors? Or diode?
Maybe the project is wrong... Look at the layout and schematics and see if something is missing, in wrong position or wrong polarity caps/diodes? Maybe even the schem is wrong... see if a positive lead is on positive voltage and negative lead on negative voltage.
Much schem have a little inverted capacitor and lots of people can't make it work... then someone says: LOOK, WRONG POLARITY! And lots of people want to kill the project guy. It happens a lot.
Quote from: NoNothing on September 13, 2007, 08:08:48 PM
I'm using this layout, and I switched the electro caps around to work with my 1Spot PS.
Hopefully that's not all you did.....
If you are switching it to a negative ground power supply, you also need to change the transistor to a NPN.
--john
Quote from: johngreene on September 14, 2007, 07:40:48 PM
Hopefully that's not all you did.....
If you are switching it to a negative ground power supply, you also need to change the transistor to a NPN.
--john
I tried using one of my Sili NPN's, and it works... BUT (and a huge but) I have the volume on my amp all the way up, and the boost on the RM all the way up, and I'm barely getting any sound... there's sound, but it's very, very faint.
So if I wanted to to be able to use a + grd RM with my 1Spot would I use the same layout (original electro orientation) and just have to wire the pos to neg, and the neg to pos??
Nyquist is very transistor sensitive. The same transistor in the same position in the circuit may act totally different. I ended up using a J201 in the first position and 5952's for the rest. It took that combination to get it to work good for me. I tried MPF102's and got it to sound ok. Try swapping transistors even if they're of the same type. Of course making sure the pin out of eacn transistors is oriented correctly is very important. I had to double and tripple check and sure enough I had one in wrong.
those single stage boosts can really be a butt sometimes :) i just slapped together the beginner project today (being not a beginner now for some time) and it worked, but i'm getting DC on the pot and i can't figure out why! it's making the pot full of static when turned. I've replaced all the electros, thinking they might be leaky, but no dice. might start a thread on this one...