Shock protection question
- Thread starter Fritz6
- Start date
Re: Shock protection question
Shock protection is a good idea, I believe.
Adrian Legg suggested another protection circuit in his book,Customising Your Electric Guitar . Use a .001 mfd 500V capacitor and parallel that with a 220k Ohm resistor. Then wire that circuit between the bridge and your ground lead, assuming your ground lead is soldered to the bridge. In a Strat it can be soldered to the vibrato spring claw. That spring cavity is an ideal place to install this circuit. This circuit lets enough voltage pass to warn you but it does not allow enough to pass to be lethal.
Shock protection is a good idea, I believe.
Adrian Legg suggested another protection circuit in his book,Customising Your Electric Guitar . Use a .001 mfd 500V capacitor and parallel that with a 220k Ohm resistor. Then wire that circuit between the bridge and your ground lead, assuming your ground lead is soldered to the bridge. In a Strat it can be soldered to the vibrato spring claw. That spring cavity is an ideal place to install this circuit. This circuit lets enough voltage pass to warn you but it does not allow enough to pass to be lethal.
Re: Shock protection question
Yeah, that's the one I've seen as well, it'll give ya about 30Volts (enough to tickle you ... :saeek: ). I don't get the whole star grounding thing as they tell it over there (as it doesn't appear to be star grounding), a cap will block DC after it's fully charged, but it still passes AC so, I can't see it being able to stop much in the way of a catastrophic amp failure, the DC yeah I can kinda see that, but even so I think you feel a bit of it. The amp/effects plugged into an Isolation transformer at the wall, and a trasformer coupled signal (amp to guitar) is about that only way to really be safe. Or wireless.
davguitar said:
Yeah, that's the one I've seen as well, it'll give ya about 30Volts (enough to tickle you ... :saeek: ). I don't get the whole star grounding thing as they tell it over there (as it doesn't appear to be star grounding), a cap will block DC after it's fully charged, but it still passes AC so, I can't see it being able to stop much in the way of a catastrophic amp failure, the DC yeah I can kinda see that, but even so I think you feel a bit of it. The amp/effects plugged into an Isolation transformer at the wall, and a trasformer coupled signal (amp to guitar) is about that only way to really be safe. Or wireless.
3
3 cent hero
Guest
Re: Shock protection question
my left hand got zapped by 110 AC volts when i was younger. and now that arm has carpal tunnel
could this be related?
:hijacked:
my left hand got zapped by 110 AC volts when i was younger. and now that arm has carpal tunnel
could this be related?:hijacked:
Re: Shock protection question
Probably not to tell you the truth, CTS is from where and tear and cpmression of the carpal tunnel against the sheath that the tendons that control the fingers ride through. Such as typing on a keyboard with the palms resting on the table.The finger and wrist are ment to be used as one unit, not separated. With the wrist fixed in one place it puts to much of a demand on the tendons controlling the finger movement,a type of over movement combined with the wrist fighting the movement. I've been hit with more than 120, and I don't have any related problems as such ... I don't plan on repeating the experience again either.3 cent hero said:my left hand got zapped by 110 AC volts when i was younger. and now that arm has carpal tunnel
:hijacked:
3
3 cent hero
Guest
Re: Shock protection question
a ha! judging by your reply, its from my bad typing habits :smack:
a ha! judging by your reply, its from my bad typing habits :smack:
Re: Shock protection question
I believe the usage of that specific capacitor in the GuitarNuts scheme is supposed to reduce the (rare) shock of a malfunctioning vintage (two-prong plug) amplifier. It has minimal effect on a AC shock caused by bad wiring (improperly-wired outlets, etc.). I believe the Legg anti-shock circuit protects better against the bad-wiring shock, but some say it is rather "noisy".
The 0.33-uF capacitor is used to isolate the shield ground (cavity shielding, strings, etc.) from the signal ground (pickup grounds, amplifier ground, etc.). So if there is a shock that "originates" from the signal ground (from the amplifier), it has to go through the capacitor to get to you. At least that's my limited understanding of it...
I wonder if anyone can (unfortunately) attest to the actual effectiveness of either of these anti-shock methods...
Fritz6 said:
I believe the usage of that specific capacitor in the GuitarNuts scheme is supposed to reduce the (rare) shock of a malfunctioning vintage (two-prong plug) amplifier. It has minimal effect on a AC shock caused by bad wiring (improperly-wired outlets, etc.). I believe the Legg anti-shock circuit protects better against the bad-wiring shock, but some say it is rather "noisy".
The 0.33-uF capacitor is used to isolate the shield ground (cavity shielding, strings, etc.) from the signal ground (pickup grounds, amplifier ground, etc.). So if there is a shock that "originates" from the signal ground (from the amplifier), it has to go through the capacitor to get to you. At least that's my limited understanding of it...
I wonder if anyone can (unfortunately) attest to the actual effectiveness of either of these anti-shock methods...
Re: Shock protection question
Thats what I was curious about. Rather than put the Legg circuit between the bridge and the central grounding point (back of pot) or the guitarnuts cap between the shield ground and signal ground, could you just solder either of them directly to the ground lug of the guitars' input jack and stop the shock before it even enters the guitar?
LH_ said:I believe the usage of that specific capacitor in the GuitarNuts scheme is supposed to reduce the (rare) shock of a malfunctioning vintage (two-prong plug) amplifier. It has minimal effect on a AC shock caused by bad wiring (improperly-wired outlets, etc.). I believe the Legg anti-shock circuit protects better against the bad-wiring shock, but some say it is rather "noisy".
The 0.33-uF capacitor is used to isolate the shield ground (cavity shielding, strings, etc.) from the signal ground (pickup grounds, amplifier ground, etc.). So if there is a shock that "originates" from the signal ground (from the amplifier), it has to go through the capacitor to get to you. At least that's my limited understanding of it...
I wonder if anyone can (unfortunately) attest to the actual effectiveness of either of these anti-shock methods...
Thats what I was curious about. Rather than put the Legg circuit between the bridge and the central grounding point (back of pot) or the guitarnuts cap between the shield ground and signal ground, could you just solder either of them directly to the ground lug of the guitars' input jack and stop the shock before it even enters the guitar?
JB_From_Hell
Jomo's Nimions
Re: Shock protection question
get a wireless system :laugh2:
get a wireless system :laugh2:
Re: Shock protection question
I don't get that, because reversing the hot and neutral on a two prong, and mis wiring the AC outlet for the same is the same. I'd like to hear the designer's reasoning on it.
LH_ said:I believe the usage of that specific capacitor in the GuitarNuts scheme is supposed to reduce the (rare) shock of a malfunctioning vintage (two-prong plug) amplifier. It has minimal effect on a AC shock caused by bad wiring (improperly-wired outlets, etc.). I believe the Legg anti-shock circuit protects better against the bad-wiring shock, but some say it is rather "noisy".
The 0.33-uF capacitor is used to isolate the shield ground (cavity shielding, strings, etc.) from the signal ground (pickup grounds, amplifier ground, etc.). So if there is a shock that "originates" from the signal ground (from the amplifier), it has to go through the capacitor to get to you. At least that's my limited understanding of it...
I wonder if anyone can (unfortunately) attest to the actual effectiveness of either of these anti-shock methods...
I don't get that, because reversing the hot and neutral on a two prong, and mis wiring the AC outlet for the same is the same. I'd like to hear the designer's reasoning on it.
Re: Shock protection question
It should work out fine, as a DC filter (your *hot* lead already has one, it's the blocking cap going into the first tube grid, or Fet, or chip ...), one on the groung side wouldn't be a bad idea ... the reason for the large value of capacitor is so that allows as much of the low audio end as possible to go to ground (when it has to) realitively uneffected. Like I said, A DC shock protection ...yeah, and AC ... I don't see that happening.
Fritz6 said:
It should work out fine, as a DC filter (your *hot* lead already has one, it's the blocking cap going into the first tube grid, or Fet, or chip ...), one on the groung side wouldn't be a bad idea ... the reason for the large value of capacitor is so that allows as much of the low audio end as possible to go to ground (when it has to) realitively uneffected. Like I said, A DC shock protection ...yeah, and AC ... I don't see that happening.
