www.radioblvd.com Those old radios were real works of Art,in and
out.And look at what excites some people nowdays,(but not me) the "fine
looks" of four bits worth of cheap plastic cabinet Eton1's and other
four bit plastic cabinet other brand names of other plastic radios and
they can't come even close to matching the sound of those big old
wonderfull tube type big speaker wooden cabinet Radios of long ago.
cuhulin

Michael Black wrote:

You'd have to go back many decades before you hit a point where
a large percentage of shortwave receivers were regenerative. Go
back forty, and some would be regenerative, albeit they'd be at
the low cost end of the spectrum. Go back to the thirties, and
regeneration likely was still common, because superheterodyne designs
used more components and hence were too costly for many in the depression
era.

Nope, nearly all radios by the early 1930's were superhet.

Brian Hill wrote:
"coustanis" wrote in message
oups.com...

....and what does it sound like?
I used to think it was a type of radio but since reading this group
I see it is a sound.

Thanks,
C-



Basically, it's when your radio receives radio waves they travel through the
tuned circuits of the RF deck or front end and depending how you have the
dial set a specific frequency will emerge and travel into the mixer section
of your radio and combine with the locally generated frequency to produce a
new frequency that is more stable and it is equal to the sum or difference
of the two. Simply to combine two frequencies to create a new frequency. The
superhetrodyne is the basis for all modern receiver designs and uses this
technique.


Out of the mixer (sometimes referred to as the converter or 1st
detector) will be four frequencies. The fundemental frequency the set is
tuned to, the local oscillator frequency, and the sum and difference of
the two.

On Thu, 10 Nov 2005 18:24:13 -0600, wrote:

www.radioblvd.com Those old radios were real works of Art,in and
out.And look at what excites some people nowdays,(but not me) the "fine
looks" of four bits worth of cheap plastic cabinet Eton1's and other
four bit plastic cabinet other brand names of other plastic radios and
they can't come even close to matching the sound of those big old
wonderfull tube type big speaker wooden cabinet Radios of long ago.
cuhulin

The Lowe HF-150 and the ICOM R-75 are both very nice pieces of
industrial design.

On Thu, 10 Nov 2005 23:33:32 -0800, Cmdr Buzz Corey
wrote:

Brian Hill wrote:
"coustanis" wrote in message
oups.com...

....and what does it sound like?
I used to think it was a type of radio but since reading this group
I see it is a sound.

Thanks,
C-



Basically, it's when your radio receives radio waves they travel through the
tuned circuits of the RF deck or front end and depending how you have the
dial set a specific frequency will emerge and travel into the mixer section
of your radio and combine with the locally generated frequency to produce a
new frequency that is more stable and it is equal to the sum or difference
of the two. Simply to combine two frequencies to create a new frequency. The
superhetrodyne is the basis for all modern receiver designs and uses this
technique.


Out of the mixer (sometimes referred to as the converter or 1st
detector) will be four frequencies. The fundemental frequency the set is
tuned to, the local oscillator frequency, and the sum and difference of
the two.
Plus intermod products of those 4 added and subtracted with each
other.

cuhulin? anyone?

In article .com,
bpnjensen wrote:
It's very important to point out that 2 different frequencies, when
mixed in a perfectly linear device, will not beat.

OK, I'll bite - why is this important in a world of radios that operate
on the heterodyne basis?

One important reason is that, in the real world, you can't have too much
gain in any one amplifier section, (in other words, on one frequency),
because the output of the amplifier can leak back to the input and the
circuit becomes an oscillator.

?And what makes a linear device different?
Are any commonly used radios linear devices?

The audio amplifier is designed to be a linear circuit. Another
word for heterodynes in an audio amplifier is "intermodulation
distortion".

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)

"Cmdr Buzz Corey" wrote in message
...
Brian Hill wrote:
"coustanis" wrote in message
oups.com...

....and what does it sound like?
I used to think it was a type of radio but since reading this group
I see it is a sound.

Thanks,
C-



Basically, it's when your radio receives radio waves they travel through
the tuned circuits of the RF deck or front end and depending how you have
the dial set a specific frequency will emerge and travel into the mixer
section of your radio and combine with the locally generated frequency to
produce a new frequency that is more stable and it is equal to the sum or
difference of the two. Simply to combine two frequencies to create a new
frequency. The superhetrodyne is the basis for all modern receiver
designs and uses this technique.


Out of the mixer (sometimes referred to as the converter or 1st detector)
will be four frequencies. The fundemental frequency the set is tuned to,
the local oscillator frequency, and the sum and difference of the two.

True but we were trying to keep it simple.

B.H.

On Fri, 11 Nov 2005 19:05:50 GMT, (Mark Zenier)
wrote:

In article .com,
bpnjensen wrote:
It's very important to point out that 2 different frequencies, when
mixed in a perfectly linear device, will not beat.

OK, I'll bite - why is this important in a world of radios that operate
on the heterodyne basis?

One important reason is that, in the real world, you can't have too much
gain in any one amplifier section, (in other words, on one frequency),
because the output of the amplifier can leak back to the input and the
circuit becomes an oscillator.

?And what makes a linear device different?
Are any commonly used radios linear devices?

The audio amplifier is designed to be a linear circuit. Another
word for heterodynes in an audio amplifier is "intermodulation
distortion".



As in the important ''IP3'' measurement which shows how well the parts
that are supposed to be linear are behaving.

"David" wrote

It's very important to point out that 2 different frequencies, when
mixed in a perfectly linear device, will not beat.


No, no, no! That's the Homodyne theory.