Bare Knuckle Pickups Forum

Forum Ringside => Tech => Topic started by: blue on August 25, 2010, 02:22:55 PM

Title: Ground Lift Switch
Post by: blue on August 25, 2010, 02:22:55 PM

afternoon folks, yet again, i seek your sage-like wisdom :)

just scored a late '60's Traynor YGA signature head.  it's had a few simple mods done to it, but it still has a ground lift switch and the original 2 core mains cable.  it came with a maplin step down transformer.

what i'm wondering is, is it safe to use as is, or should i get the ground lift switch done away with before i plug it into anything?  i want to hear what it sounds like, but i'd prefer not to get fried in the process!  i've heard conflicting messages as to the safety of ground lifts on old american amps (yes, i know, this one's canadian), but i'm sure one of the amp gurus on here can give me some sensible information.

oh, if anyone answers and i don't answer back, don't worry, i probably haven't electrocuted myself!  i'm off to Belgium later tonight for the Grand Prix :)

Title: Re: Ground Lift Switch
Post by: jpfamps on August 25, 2010, 06:04:11 PM

For safety (and for lowest noise) you should have a 3 prong mains lead fitted with the chassis grounded.

Title: Re: Ground Lift Switch
Post by: blue on August 25, 2010, 06:12:03 PM

ah, thanks.  so you wouldn't recommend turning the amp on until i get that done?

Title: Re: Ground Lift Switch
Post by: Frank on August 25, 2010, 06:16:01 PM

I wouldn't go near an amp (or any other electrical equipment) that wasn't properly grounded, isolation transformer or not. If anything goes wrong in the amp and the chassis goes live then the only route to earth for the voltage is down your guitar cable, onto your strings and through you.

Title: Re: Ground Lift Switch
Post by: blue on August 25, 2010, 06:33:52 PM

that's a very good point frank!  i may get it sorted first.  i'd prefer not to be electrocuted, if i can help it :)

Title: Re: Ground Lift Switch
Post by: blue on September 22, 2010, 02:30:38 PM

the amp is currently with mr amp tech man, although he's having a little trouble sourcing a U.S. 3 prong plug.  he thinks he has the right one ordered now, so hopefully, by the end of the week, i'll know properly what the amp is like

Title: Re: Ground Lift Switch
Post by: jpfamps on September 22, 2010, 03:22:08 PM

Quote from: blue on September 22, 2010, 02:30:38 PM

the amp is currently with mr amp tech man, although he's having a little trouble sourcing a U.S. 3 prong plug.  he thinks he has the right one ordered now, so hopefully, by the end of the week, i'll know properly what the amp is like

Rapid Electronics sell them.

I always make sure I have these in stock.

Title: Re: Ground Lift Switch
Post by: blue on September 22, 2010, 05:12:38 PM

thanks JPF, that could be useful if he doesn't get the right one.  although i just had a look and i can't find them.  any idea what they'd be called?

Title: Re: Ground Lift Switch
Post by: jpfamps on September 22, 2010, 08:15:07 PM

http://www.rapidonline.com/Cables-Connectors/Connectors-Mains-Power/Cordsets/North-American-plug-lead/72105