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I got some of the phenolic ones a while back. I'm not buying those again, as they cant take much heat before the copper comes unglued, and they also seem to be harder (takes more heat) to solder to than boards I have had in the past. Please post your experience if you decide to go for the epoxy ones, as I'm considering another order myself.

This has been mentioned, but if the transistors are 2N5088/2N5089 Q1 seems to be reversed...

Hi.

Finally got my cherrybomb to work after some frustrating debugging sessions, but it doesn't work quite as I expected. Turns out that the bass and treble controls have minimal - if any- effect on the sound, and the volume is lower than I'd expect  (unity at around Vol: 50% with Gain at 25%). I also occasionally get French radio, but this is probably due to the fact that I haven't grounded the enclosure yet. Voltages are off (see below).

Battery: 8.84V

Q1:
E: 0.38V
B: 0.93V
C: 1.92V

Q2:
E: 1.29V
B: 1.93V
C: 3.84V

Q3:
E: 0.0V
B: 1.53V
C: 8.80V

The first problem I had with this was probably due to a faulty PCB. There is 470 Ohms of resistance to ground from the emitter of Q3, as it should be, so it's not shorted to ground.

Any ideas of "suspects" is greatly appreciated

Finally got rid of the short! Partly because it was the only thing I could think of to do, and partly because I was getting rather annoyed, I used brute force and a sharp knife to cut along the tracks to the emitter of Q1, R3 and C1. And voila!

As it's well over midnight here I didn't take the time to put the box back together, but I guess it has a fair chance of working correctly this time.

Thanks for all the input, guys. I really appreciate it!

Thanks for the image. Seems like I got it right the first time. Figured the emitter was the pin closest to the tab. Now, if I can only get the base of Q1 to stop shorting to ground, they should be fine the way i put them in.

Hi.

I used the BC109. Actually I wasn't absolutely sure about the pinout, as I haven't used anything but plastic encased transistors before, but I think I got them in the correct way. I tried turning them 180 degrees when I first realized that the effect didn't work.

Now I have, as stated earlier, removed Q1 and its socket, and I am down to the bare solder pads in the section of the circuit that seems to be the problem.

Lifted C1, R3, R4, and removed Q1. Scraped the solder mask. The photo is not very good, but upon close inspection I can't see anything that looks like a copper/solder bridge. I have scraped a bit around the pads to try to make sure I wasn't missing a tiny piece of stray copper. And, yes, I have checked the top side of the PCB for solder bridges too.

Neither the non-grounded end of R4 (or R3), the positive side of C3, or the emitter of Q2 has got continuity to ground, so I haven't lifted those.

I claimed that I was running out of ideas in an earlier post, but now I'm really running dry. I'm sure I will be quite embarressed when I finally find the problem, but for now I'm kind of baffled.

Following the schematic:

Input, C1 second leg connects to ground, R3 first leg connects to ground -second leg connects to R4 - which connects (correctly) to ground, and to the emitter of Q2 (which I thought would be open to ground, but it is not). I am allmost starting to suspect that the PCB could be the problem...

I have lifted one end of R3 and R4 and cleaned up the solder, but the pads themselves are shorted to ground. The base of Q1 is still shorted to ground With R3 and R4 lifted. The gain pot has all the lugs wide open to ground when its turned fully clockwise. Could this be my problem? When the pot is tuned fully counter clockwise, lug 1 and 2 are open to ground, while lug 3 is not... Kind of puzzled here. I'm sure the solution is quite simple, but I can't seem to find it...

What do you mean you don't know which side of the component goes where? (Don't mean to sound snippy of it does)Transistors flat side are usually marked as well as IC orientation and (+) sides of polarity components are usually marked. Be happy to help, also do you have pictures?

Sorry for not expressing myself clearly. I find it harder to follow the schematic/signal path through the PCB, as the traces are not as visable as on an etched PCB. All the polarized components are mounted correctly.

Look for a solder bridge at R3 and R4 on the left side of the PCB.

Yeah. There is definitely something going on in that area. One end og R2 is grounded, as it should. But one end of both R3 and R4 is also grounded (same end og R3 and R4, but oposite of the grounded end on R2 on the PCB) I have spent some time checking for solder bridges, visually and by scraping between the solder pads, but I cant find one. I am tempted to remove them, clean the pads and put them back in.

Hi.

Cherrybomb, Madbean PCB, no sound when engaged, checked for solder bridges/cold joints.

Built a Cherrybomb last night, and have not been able to make it work. The voltages are way off (see below), and when I check for continuity, I find that the second leg of C1 is wide open to ground. I'm used to working on etched, single sided PCBs, where I can follow the tracks, but this is one of Madbeans PCBs, and I'm having a hard time figuring out which end of the component goes where.

Battery: 9.17V

Q1:
E: 0.15V
B: 0.0V
C: 8.18V

Q2:
E: 0.0V
B: 8.18V
C: 9.15V

Q3:
E: 0.86V
B: 1.47V
C: 5.76V

Any ideas? I'm starting to run out of them, so any help will be greatly appreciated. Thanks.

I have, amongst others, a Boss 9v adaptor, so I guess it will be fine for now. Will pop the zener in when I get one. Thanks!

Hi.

I have been enjoying reading this forum for a while now, and am looking forward to build some of the projects on this site.

I'm on the brink of finishing the Pork Barrel, only to find that I have forgotten to order the required 8.2v zener diode (yup, I'm using the MN3207). Will a 9.1v zener diode work as a substitute, or will it result in a fried IC?

Thanks.