A
Arfa Daily
Guest
Fender combo. Owner complained that sound level varied, or sound went off
altogether for brief periods, after a half hour of use. Additional symptom
was that the status LEDs on the footpedal flickered. He said that he'd
looked it up on the net, and many people had reported that this problem was
caused by the two ceramic feed resistors in the low voltage + and - rails,
having bad joints. OK, we've all seen this, I guess. Anyways, unit would not
fault on my bench, and no amount of pushing, prodding, poking, bashing,
heating or freezing, would provoke it, so reluctantly, I had to remove the
main board to get a look behind it. I say reluctantly, because it's a bit of
a long winded job involving removal of all of the (grub screwed) knobs, pot
nuts and washers, jack nuts and washers etc. When the board was out, I had a
really detailed look at all the joints with a powerful light and my headband
magnifier, but no joints actually looked bad anywhere, including on the two
ceramic resistors. So I went for the Mr Cook test and grabbed the wires on
those resistors one by one with pliers, and pulled. And Lo! On the third
one, it pulled cleanly and easily from the joint, leaving the now dreaded
'volcano' behind. How much longer are we going to have to put up with this
crap ? It's not as if it's the quick 'good little earner' that bad joints
used to be when you could find them in a minute or two with a Biro pen, a
can of freezer, and a Mk I eyeball ...
Arfa
altogether for brief periods, after a half hour of use. Additional symptom
was that the status LEDs on the footpedal flickered. He said that he'd
looked it up on the net, and many people had reported that this problem was
caused by the two ceramic feed resistors in the low voltage + and - rails,
having bad joints. OK, we've all seen this, I guess. Anyways, unit would not
fault on my bench, and no amount of pushing, prodding, poking, bashing,
heating or freezing, would provoke it, so reluctantly, I had to remove the
main board to get a look behind it. I say reluctantly, because it's a bit of
a long winded job involving removal of all of the (grub screwed) knobs, pot
nuts and washers, jack nuts and washers etc. When the board was out, I had a
really detailed look at all the joints with a powerful light and my headband
magnifier, but no joints actually looked bad anywhere, including on the two
ceramic resistors. So I went for the Mr Cook test and grabbed the wires on
those resistors one by one with pliers, and pulled. And Lo! On the third
one, it pulled cleanly and easily from the joint, leaving the now dreaded
'volcano' behind. How much longer are we going to have to put up with this
crap ? It's not as if it's the quick 'good little earner' that bad joints
used to be when you could find them in a minute or two with a Biro pen, a
can of freezer, and a Mk I eyeball ...
Arfa