Step 38 Questions.

[Garagedays]

This is the first kit I have ever built so I am proud to say I am only off a little bit On Step 38, it is telling me to measure R8. It should be between 13v and 14v. Mine is measuring 12v. Can someone get me past this part please

Also, need to say thank you to Tim and Seventh Circle for putting together a very organized and well thought out kit. I have only used a couple of cheaper kits to see if I had the conifidence to tacke these kits. I am definately impressed with how well things went I have 2 N72's and 2 A12's to start work on over the weekend and I can't wait to put these to use.

Tim Davis

[tpryan]

12v should be fine, depending on the power supply settings. As you use higher voltages, the voltage at R8/R9 increases. Another test is to measure the voltage at the junction of R29 and R30, which should be very close to 0v no matter where the regulators are set.

[Garagedays]

Tim,
Thanks for the reply, I have been fairly busy and haven't gotten back to this C84. I think my final question before I rack this C84 is...

U1, U 5, and U 6 are running fairly hot.

U1, I can only touch for about 4-5 seconds before it is too hot. I dont see smoke, I dont really smell anything but how hot should this opamp get?

U 5 and U 6 are fairly hot as well... How hot should these to get?

I completed my 2 A12's and 2 N72's and they are now all working I want to get this one ready for some acoustic recording I have coming up

Thanks,
Tim Davis

[tpryan]

It's normal for the op-amps to run hot, especially U1. We haven't killed one yet.

[Garagedays]

Thanks Tim. I installed it in the chassis and it is working great! Did some quick recording of acoustic guitar and do like it on that. I have heard that the J99 sounds great on acoustic as well. I love putting these together so hopefully I can order 2 J99's and 2 more A12's without upsetting the balance in my checkbook and my marriage


Thanks for your help. As always, it is appreciated.


Tim Davis