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Which of these things will kill me?

#126
Aside from the line voltage? That is pretty much "something inside the amp" that can kill you, especially our 230 volt friends.

Also, hybrid amps with solid state power amps, and amps with switchmode power supplies also have potentially lethal voltages present.
 
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#128
agedhorse said:
Aside from the line voltage? That is pretty much "something inside the amp" that can kill you, especially our 230 volt friends.

Also, hybrid amps with solid state power amps, and amps with switchmode power supplies also have potentially lethal voltages present.
Click to expand...

Sarcasm doesnt come through well on a forum. Poking around at schematics, saw this SWR hybrid with 250V up there at the top right. Yeahn you guys dont want to hit that, Haha. Good call on the switch mode also.
I was hit with 110VAC a few times at the repair shop, not fun but it wasnt that bad - didnt make very good contact and it went through my hand to ground (other hand was in my pocket) Got about 14KV from a fly back while a co op in college. Scary, but there was no current and my other hand was in my pocket. It jumped a 3-4" air gap
 

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#129
I would change the tubes in a head and bias it but that's it. It's shoes on and one hand in your pocket.
I know there is a technique for discharging a filter capacitor. Your supposed to touch the capacitor lead with the tip of a screwdriver and then touch the chassis with the screwdriver, at the same time. I've never done it though.
 
#130
Two-Spirit said:
I would change the tubes in a head and bias it but that's it. It's shoes on and one hand in your pocket.
I know there is a technique for discharging a filter capacitor. Your supposed to touch the capacitor lead with the tip of a screwdriver and then touch the chassis with the screwdriver, at the same time. I've never done it though.
Click to expand...
Oh I forgot!!! You need a variac to charge the capacitor up slowly. Otherwise it will explode capacitor guts everywhere.
 
#131
Two-Spirit said:
Oh I forgot!!! You need a variac to charge the capacitor up slowly. Otherwise it will explode capacitor guts everywhere.
Click to expand...

OP has a solid state head.
Discharge caps slowly with a bleed resistor and verify with a screwdriver across terminals and then to chassis.
Forming the caps with a variac is a good idea for longevity and its safer in case you put one in backwards.
 
#135
@jackn1202 hopefully you've concluded from multiple pages of statements and a fair amount of ribbing that there are only two mortally safe options available to you: (1) take it to a qualified amp tech or (2) put it back together and dump it at the city electronics recyclery.

The mortal hazard thing is NOT Internet folklore.
 
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#137
agedhorse said:
It doesn't?
Click to expand...
I used to service equipment that had a voltage of about 2000 V. Yes, especially tube amps can have voltage in the 500v range. Solid state may be 240v. What I would do was remove the device from power source, load still attached and power on the equipment. That would usually drain the caps.
In college we would get large caps, charge them up and throw them to people. Surprised we did not kill someone!
 
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#138
tripp2k said:
@jackn1202 hopefully you've concluded from multiple pages of statements and a fair amount of ribbing that there are only two mortally safe options available to you: (1) take it to a qualified amp tech or (2) put it back together and dump it at the city electronics recyclery.

The mortal hazard thing is NOT Internet folklore.
Click to expand...

There is a third option, taking some classes and learning about electronics and how to service it safely.

pappabass said:
I used to service equipment that had a voltage of about 2000 V. Yes, especially tube amps can have voltage in the 500v range. Solid state may be 240v. What I would do was remove the device from power source, load still attached and power on the equipment. That would usually drain the caps.
In college we would get large caps, charge them up and throw them to people. Surprised we did not kill someone!
Click to expand...

"Usually" isn't good enough when it comes to safety. Without taking proper safety precautions, "usually" gets people hurt IME.
 
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#139
I keep forgetting how dangerous the internet is.
While there is some good information in this thread, there is an equal amount of totaly incorrect, made up, junk.
On my motorcycle forums, one would get blasted for spreading any speculative tech info or just incorrect statements that had no foundation. Safety is also an issue as well as trying to help others make good repair and modification choices (based on facts).

It's not like there are no experts here who have professional training in electronics design and repair.

If you don't know for sure, look it up or stand by and be educated.
 
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