im working on an amp at the moment that is blowing fuses and when i took the protective sheeth off the mains cable-to switch i found this.one of the transformer leads was held together with masking tape! disgracefull, anyway one thing i noticed is that the neutral is being switched,surley this isnt right or common practice is it?
there is no unswitched supplies at the back of this amp like some models had
there is no unswitched supplies at the back of this amp like some models had
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It certainly isn't right Poundy , its a UK made amplifier and British electrical wiring regulations specifically state that for safety reasons the live ( USA-hot ) wire should be switched .
Which model of NAD is it ? --on opening one I have lying around positive is switched.
Which model of NAD is it ? --on opening one I have lying around positive is switched.
its a 3130.I checked my own one and its the same,this is original since i brought it from a shot in croydon in the late 80's so ill be changing that.
I have 4 others upstairs that i brough sometime ago to repair and 2 have the live switched and the other 2 the neutral is switched so it must have just been poor manufacture in some cases
This one has to be someone who messed about with it though as the transormer wire was soldered to the live mains in,and taped up with masking tape!
you couldnt make it up realy.
it had 2 blown T1A fuses when i opened it up, which is quite common with these, so im just trying to make my way through it.Strange one with this one though,the main power caps are ok, as is the bridge diode, yet resistors R448 AND R447 are very badly scorched,(still reading 100ohms each) so i havent worked out whats wrong with it yet.
not got any further but i expect to find one or both pairs of the output transistors blown.
I have 4 others upstairs that i brough sometime ago to repair and 2 have the live switched and the other 2 the neutral is switched so it must have just been poor manufacture in some cases
This one has to be someone who messed about with it though as the transormer wire was soldered to the live mains in,and taped up with masking tape!
you couldnt make it up realy.
it had 2 blown T1A fuses when i opened it up, which is quite common with these, so im just trying to make my way through it.Strange one with this one though,the main power caps are ok, as is the bridge diode, yet resistors R448 AND R447 are very badly scorched,(still reading 100ohms each) so i havent worked out whats wrong with it yet.
not got any further but i expect to find one or both pairs of the output transistors blown.
I had a look at the schematic , don't think much of the mains input wiring it seems to have been wired that way to accommodate plugging in the auxiliary equipment at the back so the live would be unswitched .
Terrible -IMHO .
Terrible -IMHO .
i think some of the versions had the sockets at the back,ive never seen one.i think most of them were continental or USA versions
I wonder if the switch has been replaced by person unknown in the past. It has a vague look of the 'universal' switches we used to use by the bucketful on various TV's back in the 80's and 90's. There were many variations and some came with a bag of different width brackets.
