Dead Hallicrafters (need help!)
 

Hello,

I am in the process of restoring an old S-120 which needed a new
potentiometer. I have replaced the part w/a new one (same type) and at this
moment, when I turn the radio on, I hear nothing but cracking sounds from
one of the resistors nearby.

I am thinking of installing a condenser (sp?) which should hold the charges
from the resistors.

Any idea if this should work, or am I lost out in this?

Thanks,
Bruno Hache
(1st year Electronics Student)

Bruno Hache wrote:
Hello,

I am in the process of restoring an old S-120 which needed a new
potentiometer. I have replaced the part w/a new one (same type) and at this
moment, when I turn the radio on, I hear nothing but cracking sounds from
one of the resistors nearby.

I am thinking of installing a condenser (sp?) which should hold the charges
from the resistors.

Any idea if this should work, or am I lost out in this?

Thanks,
Bruno Hache
(1st year Electronics Student)



Resistors aren't supposed to make crackling sounds - ever. If it is
getting hot and burning then something downstream may be shorted and
drawing excessive current thru it.

-BM

"Bruno Hache" wrote in message
...
Hello,

I am in the process of restoring an old S-120 which needed a new
potentiometer. I have replaced the part w/a new one (same type) and at
this
moment, when I turn the radio on, I hear nothing but cracking sounds from
one of the resistors nearby.

I am thinking of installing a condenser (sp?) which should hold the
charges
from the resistors.

Any idea if this should work, or am I lost out in this?

Thanks,
Bruno Hache
(1st year Electronics Student)



Why do you think it's one of the resistors? If the resistor is arcing
internally, it's best to replace it.

Crackling noises on these radios are commonly caused by arcing across the
internal mica capacitors in the IF transformers. Robert Casey has a good
article on this:

http://www.geocities.com/CapeCanaver.../repair.htm#if

Have you replace all the paper capacitors? Paper capacitors age poorly, and
also can arc internally. All of the capacitor in a waxy cardboard tube and
most of the capacitors in a molded plastic cylinder are paper. The only
plastic cylinder capacitors of this era I trust are the C-D Black Cats,
which are mylar dielectric.

Frank Dresser

Frank,

I haven't replaced the paper capacitors yet. I'll give it a try. I don't
suspect it'll hurt the unit at all.

Thanks,
Bruno Hache


"Frank Dresser" wrote in message
...

"Bruno Hache" wrote in message
...
Hello,

I am in the process of restoring an old S-120 which needed a new
potentiometer. I have replaced the part w/a new one (same type) and at
this
moment, when I turn the radio on, I hear nothing but cracking sounds from
one of the resistors nearby.

I am thinking of installing a condenser (sp?) which should hold the
charges
from the resistors.

Any idea if this should work, or am I lost out in this?

Thanks,
Bruno Hache
(1st year Electronics Student)



Why do you think it's one of the resistors? If the resistor is arcing
internally, it's best to replace it.

Crackling noises on these radios are commonly caused by arcing across the
internal mica capacitors in the IF transformers. Robert Casey has a good
article on this:

http://www.geocities.com/CapeCanaver.../repair.htm#if

Have you replace all the paper capacitors? Paper capacitors age poorly,
and
also can arc internally. All of the capacitor in a waxy cardboard tube
and
most of the capacitors in a molded plastic cylinder are paper. The only
plastic cylinder capacitors of this era I trust are the C-D Black Cats,
which are mylar dielectric.

Frank Dresser

"Bruno Hache" wrote in message
...
Hello,

I am in the process of restoring an old S-120 which needed a new
potentiometer. I have replaced the part w/a new one (same type) and at
this
moment, when I turn the radio on, I hear nothing but cracking sounds from
one of the resistors nearby.

I am thinking of installing a condenser (sp?) which should hold the
charges
from the resistors.

Any idea if this should work, or am I lost out in this?

Thanks,
Bruno Hache
(1st year Electronics Student)



First, did the radio WORK before you changed the pot????

If it was working, then the first thing you should look for is
something like solder blobs causing shorts, bare wires
touching where they shouldn't, etc.

Pete

"Bruno Hache" wrote in message
...
Frank,

I haven't replaced the paper capacitors yet. I'll give it a try. I don't
suspect it'll hurt the unit at all.

Thanks,
Bruno Hache


Your crackling resistor may be a capacitor. Specifically, an Sprague Black
Beauty. These had bands and looked something like power resistors. They
were often used for line bypasses.

Frank Dresser