another cool book

[John Larkin]

http://tinyurl.com/hsm97ny

This is the story of radio, told mostly as history and biography. The
author doesn't discuss the technology much, which is just as well
because he's fuzzy on that.

I should have paid more attention to the RCA building when I was in
NYC.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

[Cursitor Doom]

On Tue, 13 Sep 2016 19:37:01 -0700, John Larkin wrote:

> http://tinyurl.com/hsm97ny
>
> This is the story of radio, told mostly as history and biography. The
> author doesn't discuss the technology much, which is just as well
> because he's fuzzy on that.

He also seems to be a bit fuzzy on the actual inventors of radio! I can't
see any mention of Marconi, Hertz, Henry, Lodge et al. :-/

[John Larkin]

Marconi is prominent in the book. Marconi's love life is prominent,
too. Maxwell and Hertz are mentioned as background, but are not big
players in the development of radio as such.

David Sarnoff comes off better than I'd expected. He was a real
visionary. Armstrong was a good guy. De Forest was a creepy lunatic.

--

John Larkin Highland Technology, Inc

picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

[Robert Baer]

John Larkin wrote:
> On Wed, 14 Sep 2016 21:34:23 -0000 (UTC), Cursitor Doom
> <cu...@notformail.com> wrote:
>
>> On Tue, 13 Sep 2016 19:37:01 -0700, John Larkin wrote:
>>
>>> http://tinyurl.com/hsm97ny
>>>
>>> This is the story of radio, told mostly as history and biography. The
>>> author doesn't discuss the technology much, which is just as well
>>> because he's fuzzy on that.
>>
>> He also seems to be a bit fuzzy on the actual inventors of radio! I can't
>> see any mention of Marconi, Hertz, Henry, Lodge et al. :-/
>
> Marconi is prominent in the book. Marconi's love life is prominent,
> too. Maxwell and Hertz are mentioned as background, but are not big
> players in the development of radio as such.
>
> David Sarnoff comes off better than I'd expected. He was a real
> visionary. Armstrong was a good guy. De Forest was a creepy lunatic.
>
>
>
>
>
>

..and Cy Elwell?

[Cursitor Doom]

On Wed, 14 Sep 2016 15:49:04 -0700, John Larkin wrote:

> Marconi is prominent in the book. Marconi's love life is prominent, too.

Marconi's greatest love was Preece. And it was mutual.

> Maxwell and Hertz are mentioned as background, but are not big players
> in the development of radio as such.

Hertz not a big player in the development of radio?? A burger and fries
says you're wrong!

[piglet]

On 14/09/2016 23:49, John Larkin wrote:
> On Wed, 14 Sep 2016 21:34:23 -0000 (UTC), Cursitor Doom
> <cu...@notformail.com> wrote:
>
>> On Tue, 13 Sep 2016 19:37:01 -0700, John Larkin wrote:
>>
>>> http://tinyurl.com/hsm97ny
>>>
>>> This is the story of radio, told mostly as history and biography. The
>>> author doesn't discuss the technology much, which is just as well
>>> because he's fuzzy on that.
>>
>> He also seems to be a bit fuzzy on the actual inventors of radio! I can't
>> see any mention of Marconi, Hertz, Henry, Lodge et al. :-/
>
> Marconi is prominent in the book. Marconi's love life is prominent,
> too. Maxwell and Hertz are mentioned as background, but are not big
> players in the development of radio as such.
>
> David Sarnoff comes off better than I'd expected. He was a real
> visionary. Armstrong was a good guy. De Forest was a creepy lunatic.
>

Ferdinand Braun is sometimes celebrated, he brought us tuned circuits
and selectivity and multiple wireless "channels". He shared the Nobel
Prize with Marconi.

piglet

[John Larkin]

The book is about radio, stations broadcasting talk and music to
people in their homes. I don't think Hertz envisioned that.

Armstrong invented regeneration, tube oscillators, the superregen, the
superhet, and wideband FM. Not bad. The FM thing was especially
impressive, as it had been mathetically proven, and generally
accepted, that FM was inferior to AM.

--

John Larkin Highland Technology, Inc

lunatic fringe electronics

[Robert Baer]

But AHH.. the QUALITY of the sound!
(not to mention the noise rejection)

[daku...@gmail.com]

I am delighted that Marconi's name is not mentioned. To set the record straight,
Marconi plagiarized ALL the work of the
famous Indian physicist and bio-physicist
Sir Jagadish Chandra Bose. Sir Jagadish
Chandra Bose designed and built transmitters
and receivers for microwaves. Most importantly
he was the first to identify and exploit
the properties of semiconductors in his
radio physics work.

https://en.wikipedia.org/wiki/Jagadish_Chandra_Bose#Radio_research

[John Larkin]

The noise rejection was key. AM had lots of static, and restricting
the bandwidth helped some, but trashed fidelity. Carson had proved
mathematically that FM was worse, so everybody but Armstrong accepted
that. But he assumed narrowband FM and especially assumed a linear
system. Armstrong intuited that wideband modulation with limiting
receive amplifiers would work, and it did. Gain-bandwidth was
expensive in those days, so the FM signal chain was a very progressive
idea. GBW is dirt cheap now.

https://en.wikipedia.org/wiki/Edwin_Howard_Armstrong#Wide-band_FM_radio


Anyway, the book is about the people and the history, not the details
of the technology.

[John Larkin]

On Thu, 15 Sep 2016 22:56:22 -0700 (PDT), daku...@gmail.com wrote:

>On Wednesday, September 14, 2016 at 5:34:32 PM UTC-4, Cursitor Doom wrote:
>> On Tue, 13 Sep 2016 19:37:01 -0700, John Larkin wrote:
>>
>> > http://tinyurl.com/hsm97ny
>> >
>> > This is the story of radio, told mostly as history and biography. The
>> > author doesn't discuss the technology much, which is just as well
>> > because he's fuzzy on that.
>>
>> He also seems to be a bit fuzzy on the actual inventors of radio! I can't
>> see any mention of Marconi, Hertz, Henry, Lodge et al. :-/
>
>I am delighted that Marconi's name is not mentioned.

Marconi is a major character in the book.

To set the record straight,
>Marconi plagiarized ALL the work of the
>famous Indian physicist and bio-physicist
>Sir Jagadish Chandra Bose. Sir Jagadish
>Chandra Bose designed and built transmitters
>and receivers for microwaves. Most importantly
>he was the first to identify and exploit
>the properties of semiconductors in his
>radio physics work.
>
>https://en.wikipedia.org/wiki/Jagadish_Chandra_Bose#Radio_research

Marconi liked the coherer detector and didn't much like crystals or
tubes.

[Phil Hobbs]

The counterintuitive thing is that you get less noise for the same TX
power by making the bandwidth _wider_. (Only in the high-SNR limit, but
still.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

[George Herold]

On Friday, September 16, 2016 at 11:06:00 AM UTC-4, Phil Hobbs wrote:
> On 09/16/2016 02:38 AM, Robert Baer wrote:
> > John Larkin wrote:
> >> On Thu, 15 Sep 2016 19:55:19 -0000 (UTC), Cursitor Doom
> >> <cu...@notformail.com> wrote:
> >>
> >>> On Wed, 14 Sep 2016 15:49:04 -0700, John Larkin wrote:
> >>>
> >>>> Marconi is prominent in the book. Marconi's love life is prominent,
> >>>> too.
> >>>
> >>> Marconi's greatest love was Preece. And it was mutual.
> >>>
> >>>> Maxwell and Hertz are mentioned as background, but are not big players
> >>>> in the development of radio as such.
> >>>
> >>> Hertz not a big player in the development of radio?? A burger and fries
> >>> says you're wrong!
> >>
> >> The book is about radio, stations broadcasting talk and music to
> >> people in their homes. I don't think Hertz envisioned that.
> >>
> >> Armstrong invented regeneration, tube oscillators, the superregen, the
> >> superhet, and wideband FM. Not bad. The FM thing was especially
> >> impressive, as it had been mathetically proven, and generally
> >> accepted, that FM was inferior to AM.
> >>
> >>
> >>
> >>
> > But AHH.. the QUALITY of the sound!
> > (not to mention the noise rejection)
>
> The counterintuitive thing is that you get less noise for the same TX
> power by making the bandwidth _wider_. (Only in the high-SNR limit, but
> still.)
>

Do you know of someplace that it's explained. (There are links to
Armstrongs IEEE article in the Wiki link of JL's ... but
behind the pay wall.)

Never mind.. here it is..
http://michael.katzmann.name/fm.pdf
from here,
http://michael.katzmann.name/armstrong.html

George H.

[John Larkin]

Yeah, the "FM capture effect" of the limiting amp is magical.
Armstrong may have suspected it, but he did hundreds of breadboards
until it really worked.

--

John Larkin Highland Technology, Inc

[Phil Hobbs]

Limiting gets rid of the AM component of the noise but not the FM
component, so by itself it improves the SNR by only 3 dB in a narrowband
system.

Besides suppressing noise, capture prevents distant stations or adjacent
channels from changing the instantaneous average frequency of the
carrier. When you add two phasors of different lengths and similar
frequencies, the average frequency with which it loops round the origin
is just that of the larger one. The smaller one can make it bounce back
and forth, but can't make it loop faster or slower.

Normally, the detected noise density goes up as you increase the IF
bandwidth, because all the noise components intermodulate with each
other in the detector, and some of that creates baseband products.

Interestingly, because of the large carrier amplitude, the noise doesn't
intermodulate with itself much, but instead is linearly downconverted at
the frequency discriminator's output. What this does in the frequency
domain is to confine the relevant noise bandwidth to +-15 kHz of the
instantaneous carrier frequency. Thus given a fixed baseband lowpass
filter, the detected noise doesn't go up as you widen the IF, and the
detected signal gets bigger as you increase the deviation, all assuming
that you stay in the high-SNR limit. That's a cool thing that I just
learned today, from Armstrong's paper (thanks, George!). (I had thought
that the noise voltage went up like sqrt(BW), but it doesn't.)

Floyd Gardner's PLL book has a good section on loops with limiters. The
math gets fairly hairy.