Hello all.
I built the Glam pcb , but the effect is not working. I do get a bypass signal and when the effect is engaged I get signal, but there is no chorusing going on. The Green LED at the top (D2) stays lit the entire time and does not flicker. I've tried different transistors and ICs but no results. I have attached photos and voltages.
I appreciate any help that I can get.
-FOB
First, your 9v's running low, may want to replace it.
Next, any chance you could add pics of the solder side of the board, perhaps of higher resolution? Better pictures are always a good thing.
I dont think the 2399 is the root cause here. The rate LED staying on is something between the TL062, the rate and dept pots, the LED and ground. (Unless I'm reading the circuit wrong, very possible, its Finals week and I've been grading papers for 36 hours straight).
I would think the green led is the limiter led (Jon Patton's invention that's now incorporated in all Madbean's PT2399 circuits)
Have to check the schematics though.
You should maybe post pics of the solder side too.
Do you have another PT2399 you could try, just in case? Sometimes they get locked up.
When I was building the Little Angel on veroboard I got the same issue. Try to look if there's some unwanted contact between the tracks.
Quote from: Boba7 on December 10, 2016, 08:39:05 AM
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Do you have another PT2399 you could try, just in case? Sometimes they get locked up.
I agree.
I tried another pt2399 chip that I have in another functioning build. No results. Here is a pic of the solder side.
Yeah sorry my bad, D2 is indeed a rate led.
Did you try a different IC for the LFO (IC1)?
Something is going on with your power, for sure. What supply are you using and what DC does it output (without being connected to anything).
First thing I would do is pull IC2 out of its socket, reconnect the power and see what your supply is. If it suddenly bounces back up closer to 9v then the problem is in IC2...either the chip itself or possibly a solder bridge somewhere.
Bit hard to tell for sure with the picture resolution, but some of the solder does look a bit on the blobby side. Between the blue and black wires on the bottom, around the LED up top. Go in with a flashlight and check close for any little birdges (they can be sneaky at times).