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Discussion Starter #1
I am wondering if anybody knows or knows how to figure out the consumption of a Jim Dunlop UV-1? The supplied adapter is 18V and 150 mA.
 

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The adapter should indicates the potential maximum energy he makes available
(as CC from a domestic AC 110 V source)
So as I remember W = V x A = 18 V x 0,150 A = 2,7 watts which is not much.
But when you figure out an acoustic pickup pre-amp. is powered by a 9V battery...
 

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Wondering how many mA it actually pulls.
This gadget might help:

mA meter – Truetone

Forgot exactly how much it sells for at L&M. Probably around $50, but nothing outrageous.

FWIW, I once made a cable with a Boss-type barrel end that goes to my digital meter out of salvaged parts. To me, that would be a cheaper alternative to the Truetone mA Meter.
 

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Discussion Starter #6
Well that would do the trick. Can’t seem to find a cheaper alternative on amazon. Yet!!! $40.50 at L&M
 

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150Ma is not very much. Thats .15 amps. If you have a decent volt meter you can measure the current. Why is it so important to know the draw if you have the wort?
 

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I am wondering if anybody knows or knows how to figure out the consumption of a Jim Dunlop UV-1? The supplied adapter is 18V and 150 mA.
The site should list the power draw in the technical specs.
 

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Hmm, I don't see the specs online anywhere, but you can do this with a 9V power extension cable
and a multimeter if you want to save the cash for another pedal.
PM me if you need the meter.
 

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Quite often the current draw is well below what the manual, or pedal legending, might stipulate. The thing is that adapters often come in big steps, based on the regulator used or some other standardized component. So the stipulation is basically to avoid the next major step below, in order to provide the needed current. There's also the assumption that the pedal not pull so much current that it might compromise the adapter. If one was producing a pedal that drew 100ma, the recommendation would probably be to use a 300ma adapter, rather than 150ma, simply to provide the healthy margin of safety.

You CAN use a higher-current adapter than the manual indicates. If a pedal draws 43ma from a 150ma wallwart, it will also draw 43ma from a 2.5A wallwart; the same way your power brick only pulls a few amps from the wall plug that is capable of supplying 60A before the circuit-breaker blows.
 

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WOW... I thought these circuits typically blew the breakers at 15-20 amps (depending)
Yap, that 60A comment reminds me of the “magic loogie” episode of Seinfeld — that is one magic outlet at 110VAC :).

More on topic, if a pedal/circuit is digital, static/average/idle current vs. peak current can be very different. A cheap meter (or even an expensive one) will generally not have the bandwidth to measure peak current, so for those situation, a substantial amount of power supply current margin may be needed (or not, depends on power supply design). I think the OP’s pedal in question is analog, however, and that means most of what’s been stated so far does apply directly ie static and peak current will be very similar and likely small.
 

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Discussion Starter #13
Thanks for all the info. I had looked around to no avail Going to put another board together and was hoping to run everything off of one supply. The 18v a slot is only 100mA.

I believe it is analog as it is a bulb style Vibe.
 

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Most DVM's, even cheap ones, have a direct current setting with a separate input - where you drive current through the meter for measurement as compared to an inductive "clamp on" type measurement.

Unlike inductive measurements, the direct type are usually limited to low currents, often fused at 2A or less. You just need to build or mod a cable so you can put the meter in line between the power supply and pedal.

Remember to measure the voltage across the supply as well. If the wall wart supplies a higher voltage than your other, better regulated power supply, the pedal will draw less current from the wall wart than the power supply. It's all about the power, which is the product of voltage and current (P=V*I).
 
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Discussion Starter #18
Excellent site. Unfortunately the UV-1 is not listed. Similar pedals are all over the board.
 
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