Check orientation of electrolytics. I’m pretty sure bottom one needs to be flipped. I’ll be working on an NPN negative ground version and noticed this. I’ll report back.
To modify this layout to the "Goldie" version of the 1.5: change the bypass cap to a 22uf, add a 10nf cap from input to ground, add a 47K resistor between base an emitter of Q1. I pulled the 47uf filter cap and I added a trim pot in place of the 8.2k resistor. I always use carbon comp resistors in small circuits like this. Some say it's hogwash but I think it trims off some harsh upper frequencies. Sounds pretty great. Thanks for the tidy and compact layout, as always.
Question: one could replace the 8k2 resistor with a 10k pot for an external bias control, correct? Lug 1 to row 1, lug 2/3 to row 5?
ReplyDeleteYes, that exactly how to do it.
DeleteCheck orientation of electrolytics. I’m pretty sure bottom one needs to be flipped. I’ll be working on an NPN negative ground version and noticed this. I’ll report back.
ReplyDeleteOrientation fixed. Thanks for noticing.:-)
DeleteTo modify this layout to the "Goldie" version of the 1.5: change the bypass cap to a 22uf, add a 10nf cap from input to ground, add a 47K resistor between base an emitter of Q1. I pulled the 47uf filter cap and I added a trim pot in place of the 8.2k resistor. I always use carbon comp resistors in small circuits like this. Some say it's hogwash but I think it trims off some harsh upper frequencies. Sounds pretty great. Thanks for the tidy and compact layout, as always.
ReplyDelete