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Old June 6th 05, 08:43 PM
Lucky
 
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"Mark S. Holden" wrote in message
...
Lucky wrote:

"Mark S. Holden" wrote in message
...
Lucky wrote:

"Mark S. Holden" wrote in message
...
Lucky wrote:


By the way, do these fuse holders have a polarity where they need
to
be
soldered in line properly?
No of course not since you can put the fuse in the holder in either
way
or
direction. Just figured I ask. I mean if you're not 100% sure but
are
99
9/10% sure, why not close the gap on that 1/10th and ask eh?

Lucky

Not that it matters much, but I generally put the longer side of the
fuse
holder
on the side that goes to the power supply because you're less likely
to
have the
contact for the fuse touch something it shouldn't when it's unhooked
for
changing.

Hiya Mark

Yes good thinking. I can see something like that happening after
moving,
pulling or repositioning the cables. In fact,I'm going to put a tiny
piece
of tape around the holder to seal it.

BTW, should the fuse be as close to the radio or PSU? I was going to
put
it
close to the PSU since that's where all the dangerous current can
originate
from.


That's what I'd do.

1] But now I'm of the understanding I'm really protecting the PSU and
it's
environment with this added fuse more then protecting the radio
itself,
correct?


Well, if you got a big voltage spike, the fuse might blow before the
radio, but
odds are the radio will blow to protect the fuse.

2] So if it's the radio that may cause the current failure drain, then
the
fuse should be closer to the radio then the PSU correct?


No. If for example the wires between the PS and the radio got shorted
between
the PS and the fuse, the fuse won't blow, and the wires will get nice
and
hot.

I decided to do all this to protect the radio from the PSU since I'm
not
100% sure the PSU doesn't have any defects from perhaps lets say a
fall.
The
PSU could work perfectly but have a solder joint ready to break.

But I would have done this **anyway. This is my first experience with
such a
powerfull power supply that can totally fry
any electrical component conected to it. It kinda intimidates me a
little
compared to all the small low powered wall worts I'm used to

I have always put a failsafe in place in most aspects of my life. If I
can
fit a level of added security in case the major one fails I'll do it.

Remember it's always better to be SAFE then SORRY.

Always happy to hear from you
Lucky

If you want to protect the radio, your best bet is probably to add some
surge
protection - a 15v MOV hooked up on the radio side of the fuse might
help
blow
the fuse before the radio gets fried.


OK Mark,

This MOV [metal oxide varistor}, is it a component I can buy from Radio
Shack and solder in line, or is it an actual physical strip that you plug
the PSU into like a regualr surge protector?

So pick up a 15v MOV and solder it in line before the fuse closer to the
radio and the fuse holder itself closest to the PSU? Right? Wow this is
great help and advise.

Thanks a lot
Lucky


I doubt you'll find a 15v MOV at radio shack unless it's in a special
order
catalog.

It would get hooked in after the fuse, and before the radio. The hope is
the
current draw from the MOV clamping down on the voltage spike will help
blow the
fuse before your radio gets fried.

I don't think this will protect your radio from a serious spike, but
you're not
likely to spend more than a few bucks for a mov, so what the heck.


Mark,

Ratso Shackups only shows 1 MOV. Here is the product and 2nd link is the
specs.

http://www.radioshack.com/product.as...t%5Fid=276-568

specs:
http://support.radioshack.com/suppor...oc38/38010.htm

Lucky