SEX build help

[denti alligator]

Ok, three threads in one day... I know.

This will probably end up being my build help thread. I'm a total idiot with tools and so forth, so I apologize if the following question is stupid, but ...

Page 13 of the instructions: I'm supposed to be able to place a #4 nut over the threads of each #4 screw to tighten down the brackets that are holding the octal sockets.

Except, these #4 nuts fit exactly in the bracket flanges, so that they cannot be turned. I would tighten the screw on the other side (which it was the instructions suggest), but it's already been tightened and secured with a nut. So I'm at a loss as to how to secure the bracket here.

[Jim R.]

Sam,

I cheated.  I used a stack of 3 flat washers where the first nut would go, got a slightly longer 4-40 screw, and then put the nut on top (the threads protruded above the mounting ears on the tube socket), and then tightened from the top.

Hope this helps,

Jim

[denti alligator]

Well, I did it by means of loosening the first nut, threading the second, then carefully unthreading the first so that it it as close to the bracket flange as possible, then tightening both with the screw. The second nut is still not as tight as I'd like, but there's nothing to be done.

[HiFi Builder Guy]

I would tighten the screw on the other side (which it was the instructions suggest), but it's already been tightened and secured with a nut. So I'm at a loss as to how to secure the bracket here.
[/quote]

Hi Sam, I don't have the instructions handy but I believe you want to leave the initial nut a bit loose until you mount the octal socket then tighten them all at once.  Here's a link to a similar thread from the old forums.  Hope it helps

http://db.audioasylum.com/mhtml/m.html?forum=bottlehead&n=134373

[dobbykins]

Well, I did it by means of loosening the first nut, threading the second, then carefully unthreading the first so that it it as close to the bracket flange as possible, then tightening both with the screw. The second nut is still not as tight as I'd like, but there's nothing to be done.

Sam,

It's a very simple matter to now unscrew it again until the second nut comes off, then unscrew the screw another turn, until you feel it click back into the thread of the second nut (keep a finger holding the nut against the screw).  Then when you tighten it down, the second nut should be (closer to) tight.  If it still isn't satisfactory, simply repeat the process.

Best of luck,
Guy

[denti alligator]

Ok, next question. This time it's my completely my fault.

I accidentally cut both ends of one of the 220ohm 1/4W resistors that needs to go between A4 and terminal 19. (The other three are in place.) I can still fit it, but it won't be "very close" to A4 as the manual specifies. It's more like right in the middle between both terminals. So, a) is this ok? b) if not, I'm assuming these resistors at Radio Shack are the same (my local shop has them): http://www.radioshack.com/product/index.jsp?productId=2062340#

[Paul Joppa]

... I accidentally cut both ends of one of the 220ohm 1/4W resistors that needs to go between A4 and terminal 19. (The other three are in place.) I can still fit it, but it won't be "very close" to A4 as the manual specifies. It's more like right in the middle between both terminals. So, a) is this ok? b) if not, I'm assuming these resistors at Radio Shack are the same (my local shop has them): http://www.radioshack.com/product/index.jsp?productId=2062340#

Those are not the same resistors - those are carbon film, and the standard resistor is carbon composition.

It is not quite as good to space the resistor, and it is not quite as good to use carbon film (or metal film). Either or both will still probably work (prevent possible oscillation of the tube) but the probability is not quite as high.

[denti alligator]

Thanks, I made do with the short one, and it worked out fine.

The amp is up and running and sounding sweet. Thanks to Shaun (Sean?) and Doc himself for help on the phone today. And to Grainger for months' long coaching and advice.

Now I've gotta start saving for a Seduction, 'cus this Bugle pre-amp is humming it up in ways I don't remember.

[Jim R.]

Nice going, Sam!  Hope you enjoy it.

-- Jim

[Doc B.]

Hey Sam, I figured out the funny readings you were getting at A4 and B4. You were reading 100 with the volume pot turned all the way one way and 200 with it the other way. We were assuming that was 100K ohms and 200K ohms, but I realized this morning that it's an autoranging meter and you were reading 100K ohms one way and and 200 ohms - roughly the value of the 220 ohm grid stopper resistor attached to A4 and B4 - the other way.