Voltage question

Re: Voltage question

67Mopar said:
It was a generic 9VDC wall-wart. I don't recall the brand, but it was non-regulated. It's in the trash, so I'd have to did through a ton of filth to get to it.

I figured it out! Being a non-regulated supply, the DC output from the wall-wart would have increased with wall voltage. This explains the 11.3VDC reading from the wall-wart. Orlando area output gets as high as 127VAC during the day. I use a Tenma Variac and bucking transformers to keep the output level in-check for most of my gear. I am certain that I plugged the wall-wart (no variac) into the KLON during peak hours. I powered the La Grange at around 2:00AM using the same non-regulated supply. Wall voltage at this time would have been approximately 120VAC; bringing the wall-wart output down to its 9VDC spec. I should have checked the output with my meter before plugging it into anything. Live and learn...

I don't use a gang-box from my bucking transformer. My Ampeg GVT15 is the only piece of gear that goes into that unit. I plugged the wall-wart directly into the wall socket (to power the KLON) without thinking. Big mistake! I should have plugged the Ampeg and wall-wart into a power strip, then plugged the power strip into the bucking transformer... Hopefully my mishap will keep others from making the same dumbass mistake.
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Actually that trashed one was mostly likely an smps type power supply, those are the common ones these that most appliances/gadgets use. The voltage drops to the stated rating once a unit draws cureent through these. The ac voltage going up in the wall outlet wont affect their output voltage. They just need decent current draw to stabilize the output voltage. If you have to get these ones, then get a 12V one & make a diy linear regulation box using a lm7809 ic, that will let ya use these cheaper adapters with ease. I've made a few myself, doesnt need to be too fancy either.
 
Re: Voltage question

Hank- said:
Actually that trashed one was mostly likely an smps type power supply, those are the common ones these that most appliances/gadgets use. The voltage drops to the stated rating once a unit draws cureent through these. The ac voltage going up in the wall outlet wont affect their output voltage. They just need decent current draw to stabilize the output voltage. If you have to get these ones, then get a 12V one & make a diy linear regulation box using a lm7809 ic, that will let ya use these cheaper adapters with ease. I've made a few myself, doesnt need to be too fancy either.
Click to expand...
Thanks! If excessive voltage didn't cause the failure, could reversed polarity have caused it? I'm wondering if I may have inadvertently used the pigtail to my TS808 on the KLON?
 
Re: Voltage question

Fixed! The charge pump was glued down so it took a little work to get it to break free, but it's working perfectly.
 
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Re: Voltage question

67Mopar said:
Thanks! If excessive voltage didn't cause the failure, could reversed polarity have caused it? I'm wondering if I may have inadvertently used the pigtail to my TS808 on the KLON?
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Since the "standard" for pedals is center-negative, it's very possible as most other electronics that use a wall wart are center-positive. So, a generic wall wart type power adapter that isnt designed specifically for powering pedals is likely to be center-positive.

I've bought a good number of regulated "wall warts" that were center-positive and flipped the plug before using them. Most of those I bought back when it was easier to find decent, linear supplies. Today, most of the wall warts are switching supplies. Even Fulltone has discontinued their linear supplies (they were great ... nice and quiet) and gone to switching.
 
Re: Voltage question

Darg1911 said:
Since the "standard" for pedals is center-negative, it's very possible as most other electronics that use a wall wart are center-positive. So, a generic wall wart type power adapter that isnt designed specifically for powering pedals is likely to be center-positive.

I've bought a good number of regulated "wall warts" that were center-positive and flipped the plug before using them. Most of those I bought back when it was easier to find decent, linear supplies. Today, most of the wall warts are switching supplies. Even Fulltone has discontinued their linear supplies (they were great ... nice and quiet) and gone to switching.
Click to expand...
The wall-wart I was using was quite old. I reversed the polarity to center neg. some years back, which is why I came to the conclusion that it was a voltage issue. Had I reversed the polarity using the wrong pigtail, I would expect a lot more damage than just the charge pump. I don't know exactly what happened, but I'm sticking with using my Voodoo supplies from now on. I should have dug it out of the trash, then checked the output with my variac.
 
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