Ever been electroshocked by your JCM2000

[fweijers]

Did anyone measure a residual voltage on the filter caps in a JCM2000 DSL100?
I never did.

Found this thread about bleeding the filter caps:
DSL100 | Bleeding Filter Caps

I measured for voltages on R71, as said in the article, but no residual voltage at all.

My guess is that R73 and R75 discharge the capacitors for you. Is this true?
http://www.drtube.com/schematics/marshall/jcm2-60-02.pdf

Please, share your experience on this topic.
(E.g. what component should be checked for dangerous voltages)

 

[Purgasound]

I've been shocked from working DSL100. It was cool.

Got zapped on one of the wire ends going to the OT. I just discharged the amp by touching that same wire to the chassis. Makes a big spark. I don't think I'd recommend anyone else do it that way. I'm just a mutant.

The resistors you highlighted are correct. Those are directly connected to the capacitors that will hold a charge. R71 should essentially have voltage on it to, but this amp does not necessarily hold a charge for an infinite amount of time. In most cases this residual voltage will slowly bleed off after the amp is shut off. However, this isn't always the case which is why it is recommended to go through the steps of discharging the caps every time you perform work on an amp. It is a good safety practice.

 

[tresmarshallz]

got shocked biasing my SLX the other day, first time in all my years of messing around. brushed against an OT wire with my other hand on the chassis, zapp. It didn't hurt at all like I though it would, my heart did seam to beat a little differently for a day or so though.

Good for you being aware of that stuff, it is real easy to read the voltages on the caps, right, I think that is all you need to do.

 

[Adwex]

I got shocked from a car ignition coil once. It was not fun.

 

[tresmarshallz]

I got shocked from a car ignition coil once. It was not fun.

that is a powerful jolt for sure! I did the same while messing around with the distributor cap of my old mustang when my brother hit the key, thats the kind that makes your body jerk and rearranges your molecules a bit...

 

[SmokeyDopey]

I touched a 220v wall socket. For a split second, everything was white.

 

[Tbonerocks80s]

The worst is the ignition coil. Especially when you get hit in your sweaty armpit. Yikes!!!!!

 

[James442]

I'm a mechanic and I can definitely tell you working on distributor less ignition capable of 120,000 volts or so with your junk a mere fraction of an inch from the fender (a great ground) is a REALLY bad idea!

As far as the JCM2000, I've had mine apart several times lately and voltage tested the caps everytime and they always tested near zero. But as a long time automotive technician, I can tell you that the ONE TIME you fail to do that you will almost certainly live to regret it.....or not....

 

[Micky]

Years ago I worked in an automotive battery factory.
We charged/stored batteries in groups of 15, wired in series.
You needed to change your sweaty rubber gloves every 30 minutes or so.
Otherwise, they turned into pretty good conductors.
I took a shot of DC once that brought me to my knees.
Needless to say, I changed my gloves more often after that...