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5/10/2000 2:14 PM
Dave Matelitz
I recently aquired a small stone j series...sounds great however the volume drops when the effect is engaged...I know this subject has come up before answers...please help ....Thank you,Dave
5/10/2000 2:15 PM
Increase the gain of the preamp section by increasing the value of the resistance feeding the first transistor's emitter from the second transistor.  
Alternatively, put a signal booster in front of it.
5/10/2000 2:44 PM
Dave Matelitz

RG thank for your response but...could you put that in simpler terms...I am a beginner ...Thank you Dave
5/10/2000 4:37 PM
JD Sleep

If I'm not mistaken, R.G. is saying to increase the R42 resistor from 4k7 to 10k (or so) in this schematic (in the upper left-hand area of the schematic)  
If you want to see the location of R42 on the issue J board look here  
(in the lower left-hand area of the layout)  
5/10/2000 4:47 PM
Yep, that's the one. Should boost base signal by 3db.
5/10/2000 9:14 PM

Hi RG, JD, I put resistor in works great vol. the same...problem when you hit color switch up it make loud squeeling sound...any ideas...BTW.does it matter if you use 1/2 watt or 1/4 watt res. thanks dave
5/11/2000 2:44 PM
Increase R11 or decrease R12 - or both! - until the squealing stops; alternatively, just increase R9.  
All of these lower the percentage of phase line feedback that goes back into the input. With increased signal level in the line, the feedback pushes it over the edge into oscillation. Dropping the feedback a little will stop it.

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