Hallicrafters S-38 lack of sensitivity on the HF bands
 

I'm working on a Hallicrafters S-38 and have already recapped the radio
and even changed a few resistors that measured a bit high. I receive
loads of stations on the standard broadcast band, but the radio is not
nearly as sensitive on bands 2, 3, and 4. Anyone have some help with
this one? Perhaps an alignment would do the trick? Or is there
something else? Any help would be appreciated. Thanks.

Hallicrafters S-38 lack of sensitivity on the HF bands
 

"Rod" wrote in message
oups.com...
I'm working on a Hallicrafters S-38 and have already recapped the radio
and even changed a few resistors that measured a bit high. I receive
loads of stations on the standard broadcast band, but the radio is not
nearly as sensitive on bands 2, 3, and 4. Anyone have some help with
this one? Perhaps an alignment would do the trick? Or is there
something else? Any help would be appreciated. Thanks.


What are you using for an antenna?

Frank Dresser

Hallicrafters S-38 lack of sensitivity on the HF bands
 

Well, that could be a reason. I'm down in the basement with just a
short piece of wire that I connected for testing purposes. Perhaps I
should try something better. I have some dipoles strung for my ham
station. Perhaps that is all that's needed.

Hallicrafters S-38 lack of sensitivity on the HF bands
 

Hi,
Given the age of the unit, and that you have already had to replace a few
components that had changed value, an alignment would probably be in order.
Try the better antenna first and if your happy with the sensitivity than
don't worry about it. I myself would do the alignment just to be sure.

Good Luck,
RoD


"Rod" wrote in message
oups.com...
I'm working on a Hallicrafters S-38 and have already recapped the radio
and even changed a few resistors that measured a bit high. I receive
loads of stations on the standard broadcast band, but the radio is not
nearly as sensitive on bands 2, 3, and 4. Anyone have some help with
this one? Perhaps an alignment would do the trick? Or is there
something else? Any help would be appreciated. Thanks.

Hallicrafters S-38 lack of sensitivity on the HF bands
 

Well part of the my concern is that I'm working on another S-38 and
using the same piece of wire for an antenna, it picks up stations much
better and louder than the one in question. I'll get to the alignment
this week and then go from there. Thanks to all. Rod

Hallicrafters S-38 lack of sensitivity on the HF bands
 

On Mon, 6 Mar 2006 16:36:00 UTC, "Rod" wrote:

I'm working on a Hallicrafters S-38 and have already recapped the radio
and even changed a few resistors that measured a bit high. I receive
loads of stations on the standard broadcast band, but the radio is not
nearly as sensitive on bands 2, 3, and 4. Anyone have some help with
this one? Perhaps an alignment would do the trick? Or is there
something else? Any help would be appreciated. Thanks.
I am in the process of restoring two S-38's, a B and C model, in fact
just got through painting the case and starting to clean the chassis.
The radio has been recapped, but needs a new power cord. Should you
replace old cloth covered wires with modern wires also? I am new to
this so pardon my ignorance of the radios. I used to have one when I
was in jr. high and high school and wanted one for the nostalgia.
What else should one look for on the chassis to replace or
clean/replace?
Thanks


--
"What do you mean there's no movie?"

Hallicrafters S-38 lack of sensitivity on the HF bands
 

Cloth covered wiring is fine. I try not to replace things unless there will
be an improvement. Power cords can be unsafe, but the cloth usually does
not deteriorate.

Once caution about using an S-38 in the basement. Remember the chassis is
ac-dc and there can be some conduction through the floor. More than one
amateur has been killed working in a basement, when insulation failed. One
of the league's heavy hitters was killed in the 30's when his ac transformer
shorted out to a chassis and he became the path to ground.

A GFI would be a good investment in a basement when working with the old
gear.

Colin K7FM

Hallicrafters S-38 lack of sensitivity on the HF bands
 

A GFI would be a good investment

Or isolation transformer. And carefully inspect the rubber washers that
insulate the chassis from the cabinet. If they are degraded, you can get a
shock from the metal cabinet, which is now connected to your power line.
Fortunately, they are easily replaced (check the plumbing supply department
at your local hardware store).

More info about safely operating a "hot chassis" radio can be found at
http://antiqueradio.org/safety.htm .

Phil Nelson

Hallicrafters S-38 lack of sensitivity on the HF bands
 

The GFI breaker in my basement shop drives me nuts.

Yes, they can be a pain in the ... But better that than something shocking.
The isolation transformer is a good idea, although the ham I mentioned about
from the 30's was killed in a transformer operated rig, when the ac shorted
out to ground in the transformer.

Construction of a small box with a GFI outlet to only power a few items such
as the S-38 might be one alternate approach.

When in high school, I got my hand across a 1500 volt power supply and was
picked up and thrown across the room and knocked the doors off my closet. I
was dazed but unhurt. It knocked sense into me, and I have been afraid of
high voltage ever since. I now short things out two or three times before
working on high voltage and then still do not trust it. I have now gotten
to be pst middle age without any further shocking developments.

73, Colin k7FM

Hallicrafters S-38 lack of sensitivity on the HF bands
 

Rod,
Try the S 38 web page. http://www.thes38guy.com
It has everything you need to know and you can ask questions of the
S38 expert.
Mike KF6KXG

Hallicrafters S-38 LINKS
 

wrote in message
news:qon2qBoLzSnd-pn2-2LMqmkgD9OtW@localhost...
On Mon, 6 Mar 2006 16:36:00 UTC, "Rod" wrote:

I'm working on a Hallicrafters S-38 and have already recapped the radio
and even changed a few resistors that measured a bit high. I receive
loads of stations on the standard broadcast band, but the radio is not
nearly as sensitive on bands 2, 3, and 4. Anyone have some help with
this one? Perhaps an alignment would do the trick? Or is there
something else? Any help would be appreciated. Thanks.
I am in the process of restoring two S-38's, a B and C model, in fact
just got through painting the case and starting to clean the chassis.
The radio has been recapped, but needs a new power cord. Should you
replace old cloth covered wires with modern wires also? I am new to
this so pardon my ignorance of the radios. I used to have one when I
was in jr. high and high school and wanted one for the nostalgia.
What else should one look for on the chassis to replace or
clean/replace?
Thanks

Count Floyd (SCTV) was always a humorous character :-)

Web sites for various S-38 restorations and information:

Brian Ripley
http://www.thes38guy.com/Page_1x.html

Bob Piekarz - Original S38 cardboard backs (same original mfg) !
http://www.radioantiques.com/mall.html

Bill Turner's replacement electrolytic (Bob Piekarz also sells these for
Bill)
http://www.dialcover.com/caps.html

Stan Watkins
http://www.stanwatkins.com/hals38.htm

Phil Nelson
http://antiqueradio.org/halli08.htm

John's restoration
http://www.schmitzhouse.com/Johns_Electronics_08.htm

Just Radios - Capacitors (safety and others)
http://www.justradios.com/

w9gb

Hallicrafters S-38 lack of sensitivity on the HF bands
 

On 7 Mar 2006 08:53:15 -0800, "Rod" wrote:

Yeah, I know about basements and too much electricity. When I was a
kid, I learned that if I played my electric guitar in the basement, I
needed to wear shoes. Without shoes, just touching the strings on the
guitar connected to my amp resulted in quite a shock. Same thing
happened when working on the S-38. I always wear shoes when working
with electricity in my basement. And I use one just one hand, keeping
the other in my pocket. Anyway, still trying to track down why one
radio is more sensitive than the other. Perhaps some of the tubes need
to be replaced.

Swap tubes one at a time starting with the one closest to the
antenna circuit and see if the sensitivity 'moves' with one of the
tube swaps.
I have to admit it's not totally my original idea. Go here, scroll
down and start reading:

http://search.barnesandnoble.com/boo...playonl y=CHP

After replacing questionable resistors, there has been
no change.

Hallicrafters S-38 lack of sensitivity on the HF bands
 

"Rod" wrote in message
oups.com...
Well part of the my concern is that I'm working on another S-38 and
using the same piece of wire for an antenna, it picks up stations much
better and louder than the one in question. I'll get to the alignment
this week and then go from there. Thanks to all. Rod


Swapping tubes with the sensitive s-38 was also a good suggestion. Make
sure the contacts on your bandswitch are clean.

Frank Dresser