PT80 Problems High Pitch Ringing

[TheTornOne]

I went ahead and replaced the caps I had not earlier, the diodes, and the voltage regulators.

Same measurements.

Does that narrow it down to a damaged MAX1044?

[TheTornOne]

Dave I tried to use a 9V power supply and when I plugged it in the high pitch ringing went away. Than I turned the effect on and got some ungodly buzzing that almost sent me out of my chair.  It was incredibly loud.

It is an HPro Output 9V AC 1300mA, I hope this thing did not fry anything out.  I had fixed this thing before so maybe it is not working correctly?  Can someone tell me how to measure what Voltage is coming out of this thing (incredibly rookie, I know, bear with me)?

Unfortunately this is the only power supply I own, I plan to build one soon.

Thanks

[head_spaz]

nevermind...

[oldschoolanalog]

Oh man. You need a DC output power supply. Not AC output. Please study layouts & schematics a bit closer in the future. The reference to DC is on both the layout drawings at GGG.
Also, NEVER assume what is written on a wall wart is the actual V it's putting out (remember, the MAX1044 has a limit to the input V before you fry it). Always check output V of your wall warts. And make sure your polarities (+ & -) are properly oriented (don't hook up the PSU to the PCB backwards). Be 100% positive it is a DC wart unless the circuit specifically calls for an AC unit (eg: Son of Storm Tide). Always test before using.
What you did initially probably narrowed it down to a damaged MAX.
Until AC was used. Now I'm not sure. We will have to compare your V's to a working one.
I'll open mine up when I get home later & post proper working V's.
Please be patient. More damage can be done in haste than you could imagine.

Stay calm.

[jacobyjd]

ouch

[head_spaz]

This reminds me of a star trek episode... the one where:

Nurse: Jim, the PT80 has flatlined
Jim: We'll have to shock it's heart to get it started. Hand me the paddles and stand youseff back. Give me 400wattseconds. CLEAR!
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZAPPPPPPPPPPPPPPPPPPPPPP!


Nurse: Nothing Doctor. PT80 is not responding. Well.... except for the smoke.
Jim: Well then nurse, desperate situations require desperate measures. Since Fonzie isn't here to give it a good whack, reach into my goodiewampusbag and get out my HPro Output 9V AC 1300mA, STAT. That oughtta fix this sucker right up.
Nurse: Here you go Jim, but PULLLEEEZE be careful... that's AC your messing with.
Jim: Dammit nurse Ratschidtt, I wasn't born yesterday and the water is dry behind my ears, and besides, I've trained extensively with star fleet academy. Now give me that damn goodiewampus and stand youseff back.
CLEAR!  
ZZZZZZZZZZZAPPPPPPPP!

McCoy: It's no use. PT80's dead Jim. And hey, not to be rude or anything, but Dammit Jim, where did you go to mud school?
Jim: It was no use. PT80 never had a chance. May he rest in pieces... once all the smoke clears.

Stay tuned for our next episode where Captain Jimmy says:
Now, lead me to that guy with heart problems. Let's see what we can do to him................

[TheTornOne]

Well apparently I have pulled a move that is about as rookie as it gets.  I knew it was a 9V but did not look at the ratings until after I plugged it in and obviously that was incredible stupid, great haste can make great fools.

Well, to those with constructive criticism, is this build a total bomb, meaning strip the board and start over, or are there things that are salvageable if known?

Also, I think I will push up the priority on the power supply build, any suggestions would be greatly appreciated.  I read about the kits at Small Bear, and it looked like GGG had a few options.

Thanks, I will go hang my head in shame.

[head_spaz]

Ah... don't take it so hard rookie. Afterall, it's not heart surgery.

Worst case senario is that you fried all the semiconductors. But the good news is that if the diode next to the regs survived, it may have saved your butt.

I would stick with the battery until you get it working, then you should read up and get your bearings straight before you tackle a power supply. It's not rocket science... but you'll be a lot more successful if you asked questions first, and applied a little patience awaiting a response. I was working on a detailed response... but when I read what you did, I schidtt canned it, figgering it was a waste of time.

People here are good to help, but they can't drop everything the moment you need assistance. But if you give them some time, they'll bend over backwards to get you going again.
Grasshopper had to learn patience before he got his chops in kung-fu. Whereas you just earned a white belt in kung-fubar.
No energizer bunny points for you.
Bad cop! No donuts!

[jacobyjd]

Haha--that's a bummer, man. Don't feel too bad about it--the whole standard of using the SAME barrel plug for DC and AC supplies works against anyone in a hurry (I have one AC for my Whammy and 4 or 5 DC ones for everything else--same plug size).

It's not so much a rookie mistake as an issue of observation...and a dumb standard.

We'll give you a hard time because we've all ripped apart power supply sections for similar reasons at one time or another (ask some of the old dogs on this forum about their horror stories  )

I agree that you might want to use batteries to test your builds. That's what I do, since a battery will give you the cleanest power, and as long as your battery is holding steady around 9v (and your voltages aren't reversed), it can pretty much be left out of the equation when you're debugging...you can move to a DC supply for extended use once you know it's working.

[David]

Whereas you just earned a white belt in kung-fubar.

ROTFL!                 Now you, sir, should go hang your head in shame!  AT ONCE!

[Moonibopper]

Just wondering i you were able to figure out a solution. I built the PT80 from the GGG layout with the MAX1044. All the voltages are right according to the GGG files. I also hooked up the taptation tap tempo delay board http://www.google.com/imgres?q=taptation+tap+tempo&um=1&hl=en&sa=N&biw=1920&bih=995&tbm=isch&tbnid=ZUYoFeB6mIA0qM:&imgrefurl=http://www.diystompboxes.com/smfforum/index.php%3Ftopic%3D86294.260&docid=ckRDP51-gCYtIM&imgurl=http://i51.tinypic.com/r19z10.png&w=945&h=504&ei=2B3ET6DJDOrF0QGkmYDlCg&zoom=1&iact=hc&vpx=432&vpy=184&dur=423&hovh=115&hovw=215&tx=225&ty=65&sig=104394033247171753430&page=1&tbnh=113&tbnw=211&start=0&ndsp=45&ved=1t:429,r:1,s:0,i:75

I also get the high pitched sound while the pedal is engaged.

[Paul Marossy]

Whenever I hear "high pitched" ringing/whining and "MAX1044" in the same sentence I always immediately suspect that the MAX1044 chip is introducing something into the audio frequency realm that it shouldn't be.

I see this topic come up sometimes at the Parker Guitars forum because the Fly & Niteflys use a voltage doubling chip, and when the 9V battery voltage goes down below a certain level, you hear this whining coming from the guitar. Once in a while it becomes a persistent problem even with a new battery, and in one case the problem was verified to be coming from the voltage doubling chip (in this case an LT1044). Replacing the chip fixed the problem.

FWIW.

[Moonibopper]

Thanks for the help. The high pitched whining is pretty loud. Is that still consistent with the MAX1044 being an issue?

[Paul Marossy]

Well it's definitely a possibility. If it's not the MAX1044 then something else in the circuit is oscillating.

[kaycee]

For charge pump and bi-polar supplies I use the ICL7660S (the S is important as it has the booster that takes the whine out). If I remember right it is the same pin out and has a higher input voltage tolerance.

[Paul Marossy]

For charge pump and bi-polar supplies I use the ICL7660S (the S is important as it has the booster that takes the whine out).

Aha! That might be one little detail that is the source of the whole problem.