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Old 19th December 2011, 05:39 PM   #1561
billyk is offline billyk  United States
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Quote:
Originally Posted by RocketScientist View Post
@billyk, something is very likely wrong with U5 (7812). It's either the wrong part, in backwards, damaged, or somehow pins 1 and 3 are connected together. You're getting unregulated DC at the positive battery.
Excellent, thank you for the fast response, I will change it out and let you know.

Edit: That was my thought too; 23.3 x 1.4 =32.6

Last edited by billyk; 19th December 2011 at 05:43 PM.
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Old 19th December 2011, 05:46 PM   #1562
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A few things you can do for the panel are these:

-Use a steel nail as a hole punch (just a dimpler in this case). It works really well and saves money.

-With the drill bit installed and tightened and the hand drill unplugged, hold the panel in the palm of your hand and the drill head secure in the other hand. Press the panel into the drill bit at the spot you've dimpled with the punch/nail and make many, many quarter turns until a bowl is shaven into the panel. It will take a long time, so hold the panel in a way that you won't warp or deform it.

-Once the concave cup is large enough for you to feel like you can use power without the head wandering, lube it up (place a few drops of oil, alcohol, water, spit, etc.) and get ready to be dangerous.

- Make sure the panel is completely dust and debree free and cover most of it in plastic (saran) wrap (don't covor where you're drilling). Place it on an equally clean, flat, and dust-free piece of wood you don't mind destroying. Place a second piece of clean wood on top of the part of the panel that is not being drilled. Kneel or step on that upper wood block, thus sandwiching everything. This will keep it secure, and also gives you the standoff you need incase it does turn into a spinning blade. It will only hit wood, and not your body, though it may damage the panel if that occurs. You could use a shoe instead of the upper block of wood if you don't mind that the panel may whack the side of that shoe at some point.

-Go easy on the drill. I like to have the drill handle glide against my leg (when I'm kneeling) so that if it catches, the torque doesn't hurt my wrist because the drill has to move against my leg as well.

Many cordless drills have brakes so they make it easy to rub the start of a hole. I think you'll be surprised at how tough aluminum can be to work with. If I were to do this, I'd have to get different drill bits. I have these gnarly bits that make wood seem like butter and are actually designed to go through cast iron (which they do quite nicely... but it takes a while). They catch thin metal very abruptly and I would absolutely have a problem with this panel once I first made it through to the other side. I also have two bits for porcelain, but nothing for aluminum that would leave a clean hole. I'd have to go pick up some traditional twist bits.

A step drill bit is great on a press, very good for thin materials like this panel, but I don't think it's very controllable by hand, though it may feel like it is. As it enlarges to a new step it "wobbles" because it moves into the new cut area... wandering from center a little with each new enlargement.
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Old 19th December 2011, 05:48 PM   #1563
MrSlim is offline MrSlim  Canada
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Quote:
Originally Posted by regal View Post
Is there a drill template in pdf format for the taller case ?
I can email you the FPD file for it if you send me your email addy in a PM
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Old 19th December 2011, 05:54 PM   #1564
billyk is offline billyk  United States
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That did the trick! Looking at the bad part after I removed it showed a crack in the case between the metal sink and the epoxy casing...

Whenever I drill a panel I always screw it to a piece of 2x4, that hold it nicely.
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Old 19th December 2011, 05:58 PM   #1565
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Originally Posted by billyk View Post
Whenever I drill a panel I always screw it to a piece of 2x4, that hold it nicely.
Can't believe I've never thought of that before, but what a great idea! Thanks for sharing.
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Old 19th December 2011, 06:06 PM   #1566
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Originally Posted by billyk View Post
Whenever I drill a panel I always screw it to a piece of 2x4, that hold it nicely.

Oh yeah... these panels have screw holes. I wouldn't lock them down with screw-head overlap because of cosmetic threats, but since these have screw holes... that makes this much easiler.

Good call.
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Old 19th December 2011, 06:14 PM   #1567
billyk is offline billyk  United States
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Originally Posted by ethanolson View Post
Oh yeah... these panels have screw holes. I wouldn't lock them down with screw-head overlap because of cosmetic threats, but since these have screw holes... that makes this much easiler.

Good call.
Mask the holes with making tape, use wood screw with conical heads to minimize contact with the panel but still hold securely
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Old 19th December 2011, 07:15 PM   #1568
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Originally Posted by agdr View Post
Make sure your power switch is on. You won't get a voltage drop across D1 unless there is some current going through it. Does your LED still light when the power switch is turned on? Since the voltage drop across D1 will be that 0.16V - or - so make sure your DMM is on a low range, if manual, like 2V and on DC volts.

0.16V is OK for D1 on the diode test mode since it is a Schottky. Try measuring between ground and D5's cathode, see if you are getting around -12V. Then measure the voltage drop across D5.
Thanks agdr for your help. That makes sense, once I closed the circuit I got the expected voltage across D1. Every thing works now. I've also build an altoid cmoy over the weekend and the experience I got building the O2 made the much less documented CMOY an easier experience.

@RS the revised testing section and troubleshooting was very helpful. The pictures that showed the measurements for the different components I think was the most valuable to me. Thanks again for all your efforts and excellent documentation.

I almost finished another O2 with the remote pot/LED and 1/4" jack. It passed all the initial tests, but when I tried to listen there was way too much gain and as I fiddled with the pot it made all kind of noises before one of the pins snapped off. So I'll be replacing the pot soon. I gotta say the remote pot was the hardest to solder.

Her is the finished one. A thing of beauty
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Old 19th December 2011, 08:12 PM   #1569
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@hbarradh, did you rob the CMoy of its knob or did you just get two? I do like the standard knob that JDS Labs employs.
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Old 19th December 2011, 08:33 PM   #1570
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Originally Posted by ethanolson View Post
@hbarradh, did you rob the CMoy of its knob or did you just get two? I do like the standard knob that JDS Labs employs.
I order a couple from digikey. I've also got one of the wider ones for the 1/4" version. It looks really nice with the black B30 box.
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