🚀 go-pugleaf

On 01/11/2012 09:36 AM, George Herold wrote:
> On Jan 10, 9:47 pm, Phil Hobbs
> <pcdhSpamMeSensel...@electrooptical.net>  wrote:
>> On 01/10/2012 09:27 PM, George Herold wrote:
>>
>>
>>
>>
>>
>>> On Jan 10, 12:09 pm, Phil Hobbs
>>> <pcdhSpamMeSensel...@electrooptical.net>    wrote:
>>>> On 01/10/2012 01:47 AM, David L. Jones wrote:
>>
>>>>> Just thought some might be interested in hearing our recent guest on
>>>>> our Amp Hour radio show, Dr Howard Johnson of "Handbook of Black
>>>>> Magic" fame:
>>>>> http://www.theamphour.com/2012/01/10/the-amp-hour-77-winsome-waveform...
>>
>>>>> Lots of history of the book, signal integrity, Gigabit Ethernet
>>>>> development, 90 degree PCB bends, audiophoolery, and a whole bunch of
>>>>> other talk over almost 1 1/12 hours.
>>
>>>>> Dave.
>>
>>>> HJ has a mixture of good stuff and complete nonsense.
>>
>>>> I hope you grilled him a bit about his less sensible stuff, like that
>>>> hilariously erroneous video where he attempts to use electrostatics to
>>>> demonstrate that ground currents want to flow under traces.  Of course,
>>>> the impedance levels are millions of times too high for inductance to be
>>>> a factor in that demo, but never mind.    Have a look athttp://www.sigcon.com/Pubs/news/8_08.htmforthe whole ridiculous thing.
>>
>>>> (The current path is determined by corona discharge at the sharp corners
>>>> of the metal squares--if you look at all closely, you'll see that the
>>>> discharges always want to go out the corners of the squares.)
>>
>>>> Cheers
>>
>>>> Phil Hobbs
>>
>>> That is pretty silly.
>>> But certainly it's a good idea to keep a nice unbroken ground plane
>>> under the signal(s) that you really care about.
>>
>>> George H.
>>
>> I don't disagree with you there.  But I have small respect for someone
>> who makes his living peddling that sort of cargo-cult stuff.  If he ever
>> corrected himself, or offered actual real-world data or simulations, I'd
>> pay attention.  As it is, his stuff is like an old time medicine
>> show--the willow bark tea works, the snake oil doesn't, no apparent
>> effort is expended to sort them out.
>>
>> Remember the little boy in the story:  "Why do you keep snapping your
>> fingers, Bobby?" "To keep polar bears away."  "But there isn't a polar
>> bear within 2000 miles of here!"  "Works great, doesn't it?"
>
> Grin,  I've never read any of Ho Jo's books.  I figured I don't know
> enough to separate the chaff from the grain.
>>
>> Read Morrison instead.
>
> ? Ralph Morrison on Grounding and sheilding?  (the only Morrison on my
> shelf) Or someone else?
>
> George H.


Right.  Later editions have more on signal integrity.  I've been meaning 
to get a copy of the fifth edition.

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
845-480-2058

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