Thunderchild
New Member
I've just been around ebay looking at how much we may get for my dads quad 303/33/FM3 setup after fixing the amp and notice just how many cowboys there are selling "condenser kits" for the quad, some of these nuts have been selling 63 V condensers as PSU condensers. Now I know that the originals are 100 V and haven't the foggiest why quad used them as the PSU could reach 104 volts (while unlikely) and with electrolictic a fair bit of safety margin is required. When I tackled one of these sellers they said that they had never measured more than 70 V on a quad303: WHAT the flipping transformer is at least 70 V RMS never mind its peak !
For any of those planning on working on a quad be warned: you will be dealing with at least 90 Volts, with the caps replaced thats the output with no speakers connected - a very possible possibility.
Also, what on earth are 20'000 Uf going to do to a quad on it's PSU instead of 4'000 uF other than blow the rectifier and cost more than neccesary ???
Again for those embarking on quad repairs I used a pair of 2'700 uF condensers and at moderate volume when I pulled the power on the amp it kept going for about 10 seconds, seriously no joke.
Well there you go, I've said my bit !
to be perfectly safe and make sure I'm not doing the person I sell the amp to a bad turn i used 160 V caps.
For any of those planning on working on a quad be warned: you will be dealing with at least 90 Volts, with the caps replaced thats the output with no speakers connected - a very possible possibility.
Also, what on earth are 20'000 Uf going to do to a quad on it's PSU instead of 4'000 uF other than blow the rectifier and cost more than neccesary ???
Again for those embarking on quad repairs I used a pair of 2'700 uF condensers and at moderate volume when I pulled the power on the amp it kept going for about 10 seconds, seriously no joke.
Well there you go, I've said my bit !
to be perfectly safe and make sure I'm not doing the person I sell the amp to a bad turn i used 160 V caps.