What We've All Been Waiting For--700 BP boards!!!!!!!!!

Gepetto

Gepetto

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#142
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#142
The 2N5088 have very good gain on this set of transistors. To get good linearity in the pot adjustment, R62 goes from 1.87K to 5.6K and R19 goes from 1K to 270 ohms.

Unfortunately both values have to be adjusted or you end up with a hair trigger on the bias adjustment.
 
Gepetto

Gepetto

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#144
laatsch55 said:
What was responsible for all that Joe? The range was perfect on the 400's....
Click to expand...
I am pretty sure it was the stock boy again Lee :)

Some of it comes from the 10 ohms in the R35 position.

I am going to check this again when I get the second row of transistors in place.
 
Gepetto

Gepetto

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#148
Gepetto said:
I am pretty sure it was the stock boy again Lee :)

Some of it comes from the 10 ohms in the R35 position.

I am going to check this again when I get the second row of transistors in place.
Click to expand...
The bias held steady with the second row in place.

Lee see if yours copies the same as my build did.
 
Gepetto

Gepetto

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#149
Gepetto said:
The bias held steady with the second row in place.

Lee see if yours copies the same as my build did.
Click to expand...
Offset came down a slight bit with the second row in place. Now -7mV and -8mV for L and R. Bias adjusts in rock steady at about 385mV.
 
R

RainDog911

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#155
Hi Joe. Any updates or is it all wrapped up? If I see correctly, the last pictures don't have the output transistors installed.
 
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