Just finished my Cave Dweller. Build went fine, no reasons to think I made any errors anywhere.
I worked from this version and its the single 2399 baby board.
http://www.madbeanpedals.com/projects/CaveDweller/CaveDweller.pdf
Self etched - Been doing this for 5 years so I don't think its the etch.
I've checked all traces and re-flowed the board
I've double checked wiring.
I've tried 4 different PT2399's (They all sounds pretty much the same)
Checked resistor values.
Only deviation from the build guide was that I used 2 x 10K resistors in parallel because I don't have any 5K1's laying around. Although I checked the resulting resistance. All good.
Sounds great (Perhaps a little dark) and seems to work okay except that the output level is extremely low. I have to crank my preamp gain to 3 o'clock to get any usable level out of it and this obviously brings the noise floor right up with the gain. Signal to noise ratio is terrible, but that is clearly due to the low levels.
Voltages are as follows.
Regulator is putting out 5.01v so that seems fine.
(9.1v source)
1 - 5.01v
2 - 2.51v
3 - 0.003v
4 - 0.003v
5 - 3.3v
6 - 2.51v
7 - 0.61v
8 - 0.64v
9 - 16 - 2.51v.
I have searched the forum, cant find reference to the "correct" voltages. Only other guys who have the "wrong" voltages.
I have traced the signal with a probe and it seems to drop off very suddenly and expectedly after R1, being 750K I would expect that. But I can only assume that this is done to provide lower input level for cleaner repeats, and amplification happening in the gain stages of the PT2399. I was wondering if that was right, most 2399 based delays I've seen have a gain stage after the IC's output (TL072 etc...)
Has anyone had this problem? Would it be worth trying a lower value resistor at R1? I dont want to keep re-soldering this board for fear of lifting traces.
Any help would be appreciated.
I worked from this version and its the single 2399 baby board.
http://www.madbeanpedals.com/projects/CaveDweller/CaveDweller.pdf
Self etched - Been doing this for 5 years so I don't think its the etch.
I've checked all traces and re-flowed the board
I've double checked wiring.
I've tried 4 different PT2399's (They all sounds pretty much the same)
Checked resistor values.
Only deviation from the build guide was that I used 2 x 10K resistors in parallel because I don't have any 5K1's laying around. Although I checked the resulting resistance. All good.
Sounds great (Perhaps a little dark) and seems to work okay except that the output level is extremely low. I have to crank my preamp gain to 3 o'clock to get any usable level out of it and this obviously brings the noise floor right up with the gain. Signal to noise ratio is terrible, but that is clearly due to the low levels.
Voltages are as follows.
Regulator is putting out 5.01v so that seems fine.
(9.1v source)
1 - 5.01v
2 - 2.51v
3 - 0.003v
4 - 0.003v
5 - 3.3v
6 - 2.51v
7 - 0.61v
8 - 0.64v
9 - 16 - 2.51v.
I have searched the forum, cant find reference to the "correct" voltages. Only other guys who have the "wrong" voltages.
I have traced the signal with a probe and it seems to drop off very suddenly and expectedly after R1, being 750K I would expect that. But I can only assume that this is done to provide lower input level for cleaner repeats, and amplification happening in the gain stages of the PT2399. I was wondering if that was right, most 2399 based delays I've seen have a gain stage after the IC's output (TL072 etc...)
Has anyone had this problem? Would it be worth trying a lower value resistor at R1? I dont want to keep re-soldering this board for fear of lifting traces.
Any help would be appreciated.