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Projects => General Questions => Topic started by: PhiloB on February 20, 2014, 05:45:05 AM

Title: Kingslayer IC - issues
Post by: PhiloB on February 20, 2014, 05:45:05 AM
I have built a Kingslayer from an etched board.  It works but the signal is super hot/distorted. I audio probed the in on the IC and it sounds clean and the right volume.  The out on the IC is crazy hot.  I have a TLC274CN in there.  Got it from Tayda.  Just looked at SmallBear and there tlc274 had different letters following the numbers 274...believe it was acd.  Is it possible that I ordered the wrong tlc274?  Should I be looking at something else?
Title: Re: Kingslayer IC - issues
Post by: jimilee on February 20, 2014, 09:49:30 PM
Sounds like a solder bridge just right off.  Have you checked the data sheets yet?
Title: Re: Kingslayer IC - issues
Post by: madbean on February 20, 2014, 11:05:43 PM
Don't worry about the suffix N on the chip. Like Jimi said: hot IC means either a solder bridge or it is in backwards.
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 03:31:28 AM
It's an etched board.  I'll check for solder bridges.
Title: Re: Kingslayer IC - issues
Post by: gtr2 on February 21, 2014, 12:29:09 PM
Voltages might help.

Josh
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 02:19:51 PM
I'm off today.  I'll post layer
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 04:26:45 PM
Ic1 (TLC274)
1. .52V
2. .48V
3. 1.5mV
4. 9.33V
5. 1.5mV
6. 143.7 mV
7. .52V
8. .51V
9. .51V
10. .63V
11. .52V
12. 81.4 mV
13. 147.1 mV
14. .52V

IC2 (Tl1044)
1. 9.33V
2. 9.33V
3. 1.7mV
4. 2.1mV
5. .51V
6. 8.8V
7. 8.8V
8. 9.33V

I've looked but ashamed to say I can't find info on what pins should have what voltage.  I do one of these readings should be close to 18V and there is nothing close:(
Title: Re: Kingslayer IC - issues
Post by: midwayfair on February 21, 2014, 05:20:56 PM
The kingslayer is split rail (+9v/-9v), not 18V.

All the audio pins should have 0v, and the V- pin (pin 11) should be -9V. Since you don't have anything approaching -9V, and pin 5 of your charge pump isn't creating the negative voltage, that's your first issue to fix.
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 05:27:22 PM
So maybe I'm looking for a solder bridge in the part of the circuit near pin 5 of the charge pump?
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 05:29:55 PM
Thanks BTW.  Jon, is the voltage info on the datasheets and I am just being dense?
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 21, 2014, 07:24:34 PM
Here is a picture of the solder side.  Looked over it carefully and removed/re flowed a couple spots.  Am I missing something?  Voltages are still the same.(http://img.tapatalk.com/d/14/02/22/y6ajatu5.jpg)
Title: Re: Kingslayer IC - issues
Post by: davent on February 22, 2014, 12:38:33 AM
Looks to be a solder bridge to ground, third joint in- top left corner, dirt pot connection.

dave
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 22, 2014, 02:02:15 AM
Thanks Dave.  I'll see if that fixes things later this evening.  Good eye.  As my momma says 'if it was a snake it'd have bit my head off'
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 22, 2014, 03:15:36 AM
Ok.  Have a clean solder joint around the dirt pot connection.  I put a guitar signal through it again just for fun.  Where I once had too loud and distorted, I now have no output.  The signal is making it to the IC at Pin 10.  No signal coming out of the IC.  Rechecked all my voltages around the IC's again after re flowing some suspect joints but the are all the same as above
Title: Re: Kingslayer IC - issues
Post by: jimilee on February 22, 2014, 05:02:32 AM
Keep at it. Did you look at the layout to make sure everything that is still bridges is supposed to be bridged?
Title: Kingslayer IC - issues
Post by: jimilee on February 22, 2014, 05:11:38 AM
Also I confirmed with Rej on his klon, if you're running buffered out you have to have the stomp connected, BUT If your voltages aren't right, still a bridge somewhere. Does the IC still get hot? Etched boards can be tricky sometimes.
Title: Re: Kingslayer IC - issues
Post by: midwayfair on February 22, 2014, 02:20:48 PM
You still need to figure out why you don't have -9V at pin 5 of the charge pump. Time to use the continuity tester on your multimeter and make sure things that are supposed to be connected actually are. It's also possible you fried the charge pump at some point.

MIght help to see the other side of the board as well.
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 22, 2014, 02:38:35 PM
I'm at work Jon.  I'll test continuity and post a pic later tonight
Title: Re: Kingslayer IC - issues
Post by: PhiloB on February 23, 2014, 02:40:02 AM
I'm a fool sometimes.  I went home to take a picture of the top of the board and it hit me. I didn't do a good enough job on hand drilling the copper.  (I made the mistake of taping off the copper on top, still can't figure out what possessed me to do so!) I figured I'd just remove the copper around each hole.  It took forever.  Watched at least a couple hours of Olympics while doing so.  I was very careful to remove enough copper and place the components in a way that avoided contact with the copper on top.  Obviously the components must have shifted or were making contact from the start.  It would explain why I had signal to start with and not now.  Might explain why I got negative voltage on PIN 5 briefly and then not.  In my head, this complicates things to the point that I should abort, buy a prefabbed Kingslayer and start over.  Don't have the heart to etch another one right now.  At least I can salvage the pots, toggles, ICs and diodes.  At the risk of embarrassing myself I'll post the pic of the top.(http://img.tapatalk.com/d/14/02/23/ugu7a8yt.jpg)
Title: Re: Kingslayer IC - issues
Post by: jimilee on February 23, 2014, 03:18:00 AM
DDAAAAMMMNNN!!! I have never ever seen that before!
Title: Re: Kingslayer IC - issues
Post by: gtr2 on February 23, 2014, 03:34:33 AM
Yikes!   :)

Thanks for posting the pic!

Josh
Title: Re: Kingslayer IC - issues
Post by: davent on February 23, 2014, 05:27:23 AM
That's okay... before regulation almost a 700vdc differential. My first tube project, quite a few years ago.

(http://i216.photobucket.com/albums/cc305/davent/IMG_0151.jpg)
(http://i216.photobucket.com/albums/cc305/davent/IMG_4737.jpg)

dave