"Billy Brainstorm" wrote in message
...
Hi,
This unit failed to power up. Removed case and found the internal 1amp
slow blow fuse (T1AL) was shot. replaced fuse turned power on power to
unit successful as unit goes into standby mode red light on front and
clock displayed.
As soon as the unit is turned on proper the Fuse blows again.
I am a novice at this sort of thing but did some rudimentary checking on
the board that the transformer is attached to looking for blown capacitors
or a short of some kind, can anyone suggest a way forward. I am thinking
it cannot be that much wrong with it as initail power up is ok?

Oh how I wish I had a quid for every time that I've heard that. It's a bit
like saying that you have a pain in the chest, but you're sure it can't be
much because you've had pains in your arms or legs before, and they haven't
been anything serious ...



Chances are that in standby, very little other than the system control micro
is actually powered. When you attempt to take it out of standby, that's when
the main rails to (for instance) the output stages will come up. Any short
across any of the main rails, will likely take the fuse out. By far the most
common reason for such a short to be present, is failed output devices.
these might be in the form of discrete transistors, or integrated into a car
radio-type output IC, or an STK output hybrid. Without schematics, you may
not find that you can progress very far, given your admitted lack of
experience ...



I would rather attempt a repair than put it into a shop as the cost of
repair would probaly outweigh the value of the unit. any help?
suggestions?

Cheers
Billy


Hmmmm ... d:-\ }=

Arfa