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The Telephone Was Invented in Canada. I think not . . .
Sue Mansell of Waterloo, Ontario has just e-mailed me these links to Canadian history and A.G. Bell. While correctly stating that the Great One, Wayne Gretzky, is also from Brantford, although not by way of Edinburgh, Sue maintains Bell said the telephone was invented in Canada. I will need to check that statement because no claim for Bell's site of the first transmission of intelligible speech has ever been made other than Boston. Hmm. Links below now all dead
http://www.city.brantford.on.ca/Tourism_/main.htm
http://www.city.brantford.on.ca/parks_and_rec/bell_main.html
http://www.museumsontario.com/museums/musdir/belhom.shtml
http://parkscanada.pch.gc.ca/
parks/nova_scotia/alex_g_bell/Alex_g_bell_e.htm
Ericsson up to more neat things
Ericsson has just announced CDMA base stations that will support 144K data rates, part of their plan to develop 3G services. It's packet radio (internal link).You can get a great understanding of 3G and CDMA by going to their site. Here was one URL:
http://www.ericsson.se/cdmasystems/
Neat Looking Phone Cards
Mr Xu Wei e-mails from China that he is interested in old phones but instead of collecting them he collects and sells phonecards about them There are many, many fascinating telephone images at these two web sites, now dead links:
http://wwphonecards.bizland.com/phone.html and http://wwphonecards.bizland.com/oldphone.html
He also submits the most colorful address of the month: Mr Xu Wei, 204-2 Longkang Bridge, Suzhou 215008 China.
Day of the Dead
To all those who celebrate it, Happy Halloween. And soon, a joyous Day of the Dead for those who observe it. I recently attended a lecture at the Crocker Art Museum on the Day of the Dead and learned much. Día de los Muertos is not a morbid holiday but a celebration of life, of lives gone but still fondly remembered. It can be melancholy but it should not be morose. Small altars are built out things that the dead person might have enjoyed. Or symbols and tokens that the living remember the dead by. A typical altar has a photograph of the person at the center. If they liked Winston cigarettes and Budweiser beer, well, a cigarette pack and a can of that beer would be among the offerings. Perhaps their favorite walking shoes and the dog tags of a loved pet would be nestled among the flowers and candles of the altar. But the day is so much more than altar building, it is a feast and a community wide coming together of generations to remember their anscestors. This was just one of hundreds of good links:
http://www.mexconnect.com/mex
_/travel/mjmendoza/mjmdiadelasmuertos.html (external link)
The electromagnetic field and spectrum
I'm working on explaining a few things about the electromagnetic spectrum and field. It's that great, omnipresent energy force that washes over us and through us. Seemingly everything belongs to it since it includes visible light, invisible light, sound, and radio waves. Everything in matter is in fact a wave (internal link) and the electromagnetic spectrum seems to define us and everything around us by frequency. Just as you can separate radio services by frequency, so it is with each color as well. Fascinating stuff. While writing on this I came across a 1964 NASA diagram, showing the earth and the sun at calm and at disturbance with different parts of the elctromagnetic spectrum. You can click here (internal link) or on the graphic below to call up the bigger image. It's 244K but I think it is rather neat:
A Telephone System For A Hundred Bucks?
I don't get a commission on this but I think it is pretty neat, a pair of surplus German field phones that are brand new. What collectors call NOS, New Old Stock. The cost is $80. Throw in $20 worth of wire and you are all set. This little system could be used for demonstrations, to convincingly show how simple a telephone system can be and how the telephone is an electrical instrument. I have the URL below for more info. You need to enter the product code in their search engine to locate the right page.
Here's the text of the ad from the HeadQuarters catalog: "This 2-Phone Set is ready for field communications or mint-condition collectibility. Each plastic-cased unit (with hinged top) has a webbing shoulder strap. Heavy-duty plastic handset with a "push to talk" lever and a 31/2' insulated cord. Hand crank rings the other phone. The international radio code, from "alpha" to "zulu" is on the case cover. Quality circuitry from Germany's "Standard Elektrik"...plus] old-fashioned cool looks. Operates on 2 D batteries (included) Comes with translated English instructions. Each 10x43/4x63/4" h. unit weighs 91/2 lbs. Wire not included, order below. Condition: brand crankin' new, never issued. Call me to get in on this rare surplus bargain!"
http://www.sportsmansguide.com/ (external link)
HURRY! Sale Prices Expire On 3/4 Order Numbers:
AX1M - 50302 - Set of 2 New German Mil. Field Phones $79.97
AX1M - 43288 - 500 yds. of New 2-Strand Swiss Mil. PhoneWire, Olive Drad ($14.97)
A small jokes and quotes page
I've wanted to put together this quotes and jokes page for a long time. It's not too lengthy right now but I will add to it from time to time. Please contribute!
Simple Telephone Circuit
Oh, do you want to know how simple a telephone circuit can be? Here's a big graphic that demonstrates all the principles.(internal link) It's 120K or so but very interesting. It demonstrates that you can wire two telephone handsets together and with a power supply have a telephone system.
Misc. e-mail
Just some of my correspondence in the last two days; everyone is trying to figure out how things work:
Q. Can you describe in detail how the microprocessor in a cell phone works (not the DSP)?
A. No, I am sorry, I cannot. Microprocessors and the like lie squarely within the field of data com which I have avoided. I would wind up searching http://www.google.com (external link) or deja.com for a tutorial just like you. And I have not found anything simple on DSP, by the way. Sorry that I could not help. Best, Tom Farley
Q. I found your pages on cellular phone is really helpful. Do you know where I can find more information on the OnStar system? I could not seem to get enough technical detail on how it works, i.e in emergency situation. Is there such a tutorial somewhere on the internet?
A. I have not investigated this subject at all. There is this FAQ, of course:
http://www.onstar.com/visitors/html/ao_faq.htm
Beyond that you may want to do some patent searching under the term "roadside assistance" at the United States Patent and Trademark website (external link). Information overload! You might have a little difficulty finding out where the patent is or a patent close to it but when you do, you will hit a gold mine. I do not know if it is GM technology or if they are sub contracting the work from an independent sat service. Or go to deja.com and search for On-Star or some such to see what the telecom groups are saying about it. If anything. Wish I could have helped, best, Tom Farley
Q. Hope you don't mind me emailing you so feel free to ignore this if you wish. If you don't, I wonder if you could help me. Why is is not feasible to use the same frequency for Radio 4 on a nationwide basis?
I'm not sure I understand your question. Radio 4 sounds like an English broadcasting service, perhaps? In general most AM and FM broadcasting stations are limited to a certain power so that they don't interfere with other broadcasting stations in nearby cities. Each city has to be able to carry their own local radio programming or the public is not served. So you have dozens of stations, perhaps hundreds, all sharing the same frequency across a country. It would then be impossible for one frequency to be set aside for one station. This is actually a country wide example of frequency reuse, the defining principle of cellular (internal link). Let me know if this is not what you are talking about.
Q. And do you know where I can get diagrams of PAM, PPM, and PDM on an oscilloscope?
A. I have no idea but I would check out who makes oscilloscopes and test instruments and then check out their web sites. You might get lucky. And try oscilloscope over at Altavista.com in their "Images search" feature. Keep looking, you will find it. Best, Tom Farley
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