May 14, 2020 at 4:31 pm #12891
impressed and inspired by Scott Prestons combo pedal (https://guitarpcb.com/forums/topic/a-mash-up-of-two-classic-cornish-style-pedals/) I’m building a combo by my own.
The animal side doesn’t work so I’m trying to find the problem. I checked the build document once again and realized that when using a wiring board, or a BuffNBlend as I do, I have to ignore S4-S6. But there are still S1, S2, S7 and S8.
Am I right by checking the schematic and looking at Scott Prestons pictures that I have to jumper S1-S2 and S7-S8?
HenrikMay 14, 2020 at 5:13 pm #12893
Yes try that I did that with my G 02 build when mine didn’t fire up, jumpering S1 and 2 and S7 and 8 cured itMay 14, 2020 at 6:37 pm #12895
now it works.
HenrikMay 19, 2020 at 1:41 pm #12978
I need your help again. The Animal doesn’t work properly.
When I turn on the effect, there is a permanent sound and if I play my guitar, it sounds terribly wrong on top. [Here is an mp3 I recorded to my post here as an example]
The guitar signal gets through the circuit. The LED and the bypass are working. I put the pcd out of the enclosure, used it without the BuffNBlend, the same problem. I used it with battery, the same sound.
The pots seem the be ok, checked them with my multimeter. The 6 Transistors 2N5088 seem to work, Q1-Q6 have the voltage descripted in the building manual, with a few percent difference here and there. I checked the wires and the polarity of the components when there is any. I checked the diodes (LEDs) with MM, they seem to work. The solder points should be ok, checked them and re-soldered here and there. I cannot find a reason for the problem.
What should I do now? What could cause such a sound?
Some help would be really appreciated.
HenrikMay 19, 2020 at 8:12 pm #12982
Check all your transistors are seated securely in their sockets Henrik I’d also untangle the blue and black IN wires
I actually think it sounds like an old casio keyboard you may have inadvertently found a cool mod!
Anyway check your transistors are in the sockets nice and secure
All your resistor values etc look correct but can’t see R32, 34 or 37May 24, 2020 at 3:40 pm #13053
thank you for your help so far. I’m still trying to get the circuit work.
A pin of the Volume pot broke yesterday when I was soldering, so perhaps it was damaged before. As far as I understand the schematic, the pot is a voltage divider. So i can simply go from pin3 to Out and it would be like the Volume pot all the way up, right?
And if the Volume pot is a voltage divider, could I use a A50k instead of the broken A10K? Would there be any difference? (I have one left so I would not have to wait for a new one)
HenrikMay 25, 2020 at 1:51 am #13059
Pin 2 is the volume pot output goes to R38 junction
You may be able to use the pot if you can still solder to it
Any pot should work it may not act as it should ie bunch up across it’s range
You can alter resistance by putting a resistor across lugs 1 and 3 to change your 50KMay 25, 2020 at 10:26 am #13061
So I have to put a 12,5k resistor parallel to the 50k pot and it’s like the needed 10k pot.
I’ll try. Hopefully I can make the circuit work soon, my motivation dreclines more and more.
HenrikJune 15, 2020 at 1:55 pm #13312
Yesterday I had the time to try again . Ein built an audio probe like it is described in the building instructions. With the Audio probe i checke the circuit. And on the entrance of the resistor R26 the signal wars normal. But on the other side of the resistor it was massively distorted. Checked with a Multimeter it shows 8.1k.
Could the resistor be damaged so that the audio signal gets distorted in some way?
And if it is damaged: I have several resistors at home. A 10k and a 5,6 K resistor are the nearest. Can I use one of them or should I take some resistorsparallel or serial to get to the 8, 2K?
Thank You ,
HenrikJune 15, 2020 at 10:31 pm #13316BarryKeymaster
The first thing I would do is a solid re-flow of everything in that area of the circuit including making sure transistors are properly seated as well. Flip it over and work the back of the board and re-flow all solder joints
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