Seventh Circle Audio

by **Nu-tra** » Thu Nov 10, 2005 8:55 am

I'vebuilt five A12'S so far and they have all been about +-18v on both the negative and positive pin 3 and 5... Before twaeking the amount to +-16v Now this last one I made was at +-20 on pin 3 and 5 before tweaking.. On your instruction manuals it says I shouldbe getting +-14v
I looked over the last 4 pres i built and everthing looks ok... Any suggestions?

V

by **tele_player** » Thu Nov 10, 2005 9:14 am

Double check the values of the voltage-setting resistors: R29,R30,R31 and R25,R26,R27, and make sure D5 and D7 are oriented correctly.

by **tpryan** » Thu Nov 10, 2005 9:15 am

Are you saying you can't adjust the voltage below +/-20V? Did you follow step 31?

by **Nu-tra** » Thu Nov 10, 2005 7:33 pm

No I can adjust it.. Is it too high from the get go is all... Yourinstructions say I should see +-14 I've been seeing +-18-20 is this ok?

by **tele_player** » Thu Nov 10, 2005 8:10 pm

When you adjust it, what's the lowest voltage reading you can get?

by **Nu-tra** » Fri Nov 11, 2005 1:08 am

about 14

by **tele_player** » Fri Nov 11, 2005 2:26 am

That means you didn't do step 31 in the instructions (turn R25 and R29 full counter-clockwise), which sets the voltages as low as possible.

In other words, there's nothing wrong.

by **Nu-tra** » Fri Nov 11, 2005 11:00 pm

Thanks! I totally misunderstood the step... I thought I was supposed to see the lowest when I first powered it up.

Have a great weekend...

Seventh Circle Audio

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