How's this Zenith G500 look?
 

I'm looking for my first tube shortwave radio. I'm not too good with repairs
besides simple soldering. I want the radio to actually work well and be usable
to hear far away stations as well as look cool. For an inexperienced person
like myself that wants a working vintage shortwave without too much in depth
repairs, does this look like it could be ok? I read that a lot of you have this
model. So it seems to be well-loved.

http://cgi.ebay.com/ws/eBayISAPI.dll...fromMakeTra c
k=true

Doc Gorpon wrote:

I'm looking for my first tube shortwave radio. I'm not too good with repairs
besides simple soldering. I want the radio to actually work well and be usable
to hear far away stations as well as look cool. For an inexperienced person
like myself that wants a working vintage shortwave without too much in depth
repairs, does this look like it could be ok? I read that a lot of you have this
model. So it seems to be well-loved.

http://cgi.ebay.com/ws/eBayISAPI.dll...fromMakeTra c
k=true

A concern I should have mentioned in my reply in the other thread is
tube radios often need to have the capacitors replaced for safety reasons.

Since any tube radio is probably going to need recapping,
and the OP is inexperienced at this, a better choice to start
might be a Halli S-38 or the comparable National. These radios
have a lot more room under the hood and the inevitable re-capping
job will be much easier. After getting some experience, he'll be
ready for something like a T/O.


Mark S. Holden wrote:
Doc Gorpon wrote:

I'm looking for my first tube shortwave radio. I'm not too good with
repairs
besides simple soldering. I want the radio to actually work well and
be usable
to hear far away stations as well as look cool. For an inexperienced
person
like myself that wants a working vintage shortwave without too much in
depth
repairs, does this look like it could be ok? I read that a lot of you
have this
model. So it seems to be well-loved.
http://cgi.ebay.com/ws/eBayISAPI.dll...fromMakeTra c

k=true


A concern I should have mentioned in my reply in the other thread is
tube radios often need to have the capacitors replaced for safety reasons.

On Thu, 7 Oct 2004 14:05:37 -0500, Larry Ozarow wrote
(in article 5sg9d.3650$Ua.1899@trndny01):

Since any tube radio is probably going to need recapping,
and the OP is inexperienced at this, a better choice to start
might be a Halli S-38 or the comparable National. These radios
have a lot more room under the hood and the inevitable re-capping
job will be much easier. After getting some experience, he'll be
ready for something like a T/O.


You're recommending /starting/ with 5-tube AC/DC's?

Do you really think that's a good idea? I started with a S-38B and
added a Heath Q-1 and I would /never/ recommend starting there ('course
I was 12 years old and invincible).



Gray Shockley
--------------------------
Entropy Maintenance Technician
Tao Chemical Company
--------------------------

http://www.compcomm.com/
Vicksburg, Mississippi US

My impression was that this was for a first "tube"
radio, not first radio of any kind. My recommendation
was not based on ease-of-use of course, but on
"ease-of-getting-into-decent-working-order." A fellow
with very little radio repair experience will have
a much harder time getting the average e-bay T/O
up to snuff.

Obvously there are better choices than either
a T/O or an S-38 out there, but they require more
dough to purchase and more skill to maintain.

Oz




Gray Shockley wrote:
On Thu, 7 Oct 2004 14:05:37 -0500, Larry Ozarow wrote
(in article 5sg9d.3650$Ua.1899@trndny01):


Since any tube radio is probably going to need recapping,
and the OP is inexperienced at this, a better choice to start
might be a Halli S-38 or the comparable National. These radios
have a lot more room under the hood and the inevitable re-capping
job will be much easier. After getting some experience, he'll be
ready for something like a T/O.



You're recommending /starting/ with 5-tube AC/DC's?

Do you really think that's a good idea? I started with a S-38B and
added a Heath Q-1 and I would /never/ recommend starting there ('course
I was 12 years old and invincible).



Gray Shockley
--------------------------
Entropy Maintenance Technician
Tao Chemical Company
--------------------------

http://www.compcomm.com/
Vicksburg, Mississippi US

On Fri, 8 Oct 2004 06:57:28 -0500, Larry Ozarow wrote
(in article Igv9d.2785$Ua.169@trndny04):


My impression was that this was for a first "tube"
radio, not first radio of any kind.

I wasn't specific enough.

The 5-tube/valve AC/DC's are probably the
most dangerous radios ever made.

You might wanta take a look:

http://antiqueradio.org/safety.htm


gray

My recommendation
was not based on ease-of-use of course, but on
"ease-of-getting-into-decent-working-order." A fellow
with very little radio repair experience will have
a much harder time getting the average e-bay T/O
up to snuff.

Obvously there are better choices than either
a T/O or an S-38 out there, but they require more
dough to purchase and more skill to maintain.

Oz




Gray Shockley wrote:
On Thu, 7 Oct 2004 14:05:37 -0500, Larry Ozarow wrote
(in article 5sg9d.3650$Ua.1899@trndny01):


Since any tube radio is probably going to need recapping,
and the OP is inexperienced at this, a better choice to start
might be a Halli S-38 or the comparable National. These radios
have a lot more room under the hood and the inevitable re-capping
job will be much easier. After getting some experience, he'll be
ready for something like a T/O.



You're recommending /starting/ with 5-tube AC/DC's?

Do you really think that's a good idea? I started with a S-38B and
added a Heath Q-1 and I would /never/ recommend starting there ('course
I was 12 years old and invincible).



Gray Shockley
--------------------------
Entropy Maintenance Technician
Tao Chemical Company
--------------------------

http://www.compcomm.com/
Vicksburg, Mississippi US

OK Gray, I stand corrected.
He should buy an S-38 AND an
isolation transformer.

By the way the most dangerous radio
ever made is likely to be that
Bell&Howell that Al Patrick uses to
listen to Jackie Patru and Petie
Peters.

Oz

Gray Shockley wrote:
On Fri, 8 Oct 2004 06:57:28 -0500, Larry Ozarow wrote
(in article Igv9d.2785$Ua.169@trndny04):


My impression was that this was for a first "tube"
radio, not first radio of any kind.


I wasn't specific enough.

The 5-tube/valve AC/DC's are probably the
most dangerous radios ever made.

You might wanta take a look:

http://antiqueradio.org/safety.htm


gray

"Gray Shockley" wrote in message
.com...



The 5-tube/valve AC/DC's are probably the
most dangerous radios ever made.

You might wanta take a look:

http://antiqueradio.org/safety.htm


gray


The prewar "curtain burner" cord sets have an interesting approach to making
an AC/DC radio. These radios used a 300 ma series string for the tube
heaters, rather than the later 150 ma string. The 300 ma string added up to
only about 60 volts. The other 60 volts was dropped in a third resistance
wire in the cord. Running the cord under the carpet was a bad idea.
Wrapping the cord up in a neat bundle was a bad idea. As the informal name
suggests, the cord itself was a bad idea.

It's worth mentioning that tube battery sets which have the option of power
line operation are also AC/DC radios. Just about every AC/DC set from about
1950 onwards uses a floating ground bus, which is somewhat safer than a true
hot chassis. I have a prewar GE battery/AC/DC set, which is certainly of
the more dangerous radios ever made. It has a true hot chassis, with one
side of the line cord firmly soldered to the chassis. The chassis is
mounted upside down, and the chassis attaching screws are mounted near the
radio's handle and knobs, without any electrical isolation. It also had a
curtain burner cord to drop voltage for the heater in the rectifier tube.

Not all hot chassis radios used tubes. I've got a hot chassis solid state
RCA from around 1967 in my pile 'o junk. If I recall, the radio circuits
are used as a sort of emitter resistance (bypassed with an electrolytic) for
the audio power output transistor. They went to a fair amount of effort to
eliminate a small power transformer in a transistor radio, and they ended up
having to use an audio output transformer instead. I think I've read that
DC was still used in some parts of the east coast up into the sixties, and
radios such as this may have been designed with that market in mind.

None of this compares with the direct coupled output transformerless tube
amps some homebrewers like to play with. They use four of the 25 volt
heater variants of the 6080 voltage regulator tube in a series heater
string, with another tube, something like a 12AX7, for a phase splitter.
Half of the power triodes are hooked up as cathode followers directly
coupled to a speaker, and the other half of the triodes are used as an
active load for the cathode followers, much like the common totem pole
output often seen in transistor output stages. The power is rectified right
from the line cord with two solid state rectifiers, one for the positive
supply, another for the negative supply. Yikes!!

Frank Dresser

"Brian Hill" wrote in message
...



I wounder how many met their maker with these death trap sets?



The curtain burner cord sets must have been, by far, the most dangerous.
Smoke and fire are a far bigger threat to groups of people than accidental
contact with electricty. There were a couple of safety improvements in
AC/DC radios and transformerless TVs over the years. First, the true hot
chassis was eliminated. Then protruding metal shafts were eliminated.
Either the plastic knobs had their own hollow shaft to reach down to a metal
control shaft or the controls had plastic shafts.

The last reference I have to a curtain burner cord is in the 1947
Hallicrafters sales flyer. They say they could supply a resistor cord so
the S-38 could be operated on 220 volts. This cord would have been required
to dissapate considerably more power than the usual 1930s curtain burner.

I like to rewire AC/DC sets so the switch opens up the hot wire rather than
the neutral, I install a polarized or three wire cord and I put in a fuse.
I didn't rewire the switch on my Hallicrafters TW 1000 battery set, however.
The radio uses the same switch to switch the line power and the battery
power, and I didn't bother trying to figure out how to make it work right.
I do use it on AC but I don't have it plugged in when I'm not around.

Frank Dresser

Frank Dresser wrote:



The prewar "curtain burner" cord sets have an interesting approach to making
an AC/DC radio. These radios used a 300 ma series string for the tube
heaters, rather than the later 150 ma string. The 300 ma string added up to
only about 60 volts. The other 60 volts was dropped in a third resistance
wire in the cord. Running the cord under the carpet was a bad idea.
Wrapping the cord up in a neat bundle was a bad idea. As the informal name
suggests, the cord itself was a bad idea.

It's worth mentioning that tube battery sets which have the option of power
line operation are also AC/DC radios. Just about every AC/DC set from about
1950 onwards uses a floating ground bus, which is somewhat safer than a true
hot chassis. I have a prewar GE battery/AC/DC set, which is certainly of
the more dangerous radios ever made. It has a true hot chassis, with one
side of the line cord firmly soldered to the chassis. The chassis is
mounted upside down, and the chassis attaching screws are mounted near the
radio's handle and knobs, without any electrical isolation. It also had a
curtain burner cord to drop voltage for the heater in the rectifier tube.


Some people attempt to correct the AC/DC hot chassis problem by
replacing the plug with a polarized plug, but on AC/DC sets the on/off
switch almost always switches the side of the line going to chassis or
common. So even with a polarized plug, when the set is switched off
there is a path from the hot side of the line through the filaments to
common, so the shock hazard still exists. When using a polarized plug,
the set needs to be rewired so that the on/off switch interrupts the hot
side of the AC line.