SBE CHAPTER 40 NEWSLETTER
MARCH 2002
San Francisco
Roy Trumbull - Editor roy547@msn.com
Bill Dempster - Artist
Advertisers for this month's newsletter are:

Zack Electronics - Judi Lomas - (888) 329-0225
Advanced Marketing - Frank A. Santucci - (650) 365-3944
Belden - Steve Lampen - (415) 440-8393
Orban - custserv@orban.com - (510) 351-3500
MARCOM - Martin Jackson - (408) 768-8668
William F. Ruck, Jr. Broadcast Engineer - (415) 564-1450
Audio Accessories - Rosie Alexander - (510) 787-3335
Kathrein (Scala Division) - Michael Wm. Bach - (541) 779-6500
Hammett & Edison, Inc. - Dane E. Ericksen, P.E. - (707) 996-5200
LeBLANC - David A. Hill - (650) 574-4600
Gentner Communications - Kelly Hanning - (800) 879-9317
Improbable Missions Fource - Mike Schweizer - (888) 4-ISDN4U
Econco - George Badger - 650-327-7599
RF Specialties of California - Bill Newbrough - (888) 737-7321
ADC - Russ Erickson - (877) 440-7877
Enco Systems - Steve Rooney - 800-ENCO-SYS

Babes/SBE Luncheon on Wednesday Mar 27th

This month we'll have a presentation about the BMS Microwave Carry-Coder which is a COFDM box. These units are know for staying locked while the transmitter is in motion.

As usual, our luncheon will be at Sinbad's just south of the Ferry Building on the Embarcadero near the foot of Mission St. We meet at 11:30 and are seated at 12:30. To make reservations call Paul Black at 925-827-9511 and leave a message on his machine.

SMPTE iBlast Meeting

This month there will be a SMPTE meeting March 28th at the Garden Room of the RoundTable Pizza in Menlo Park, 1225 El Camino at Oak Grove Av. Buy your own dinner from 6:30 - 7:30.

Peter Lude' of iBlast will talk about using DTV data transmissions for internet connections thereby getting around the bottleneck of the internet server farms. The internet will be as close as a receiver card in your PC. Recent improvements in DTV receivers, 8VSB demodulation technology, antennas, and software applications are allowing the creation of a wireless data broadcast infrastructure. Within the last few months, the first thousand end-users have subscribed to various datacasting services across the country, with strong growth projected in the next several years.

Lo-Band TV and DTV

There are only two lo-band DTV stations on the air in the U.S. They are WKYC in Cleveland and WBBM in Chicago. At the ATSC web site (www.atsc.org) there is a paper dated Dec, 2000 of a study to compare 8VSB to COFDM. One of the tests was done at WKYC. The 8VSB did better than COFDM because COFDM gets killed by impulse noise and the lo-band is loaded with it. That said, there were a surprisingly low number of test sites that received either signal in comparison to the other three studies that involved UHF stations. It remains to be seen if lo-band is viable at the power levels granted by the FCC.

Last year at the fall IEEE conference a paper was given entitled: "DTV Coverage and Service Prediction, Measurement, and Performance Indices". Its authors were Oded Bendov, John F.X. Browne, Charles W. Rhodes, Yiyan Wu, and Pierre Bouchard. It seriously questions whether the planning factors used by the FCC for DTV are realistic.

Oded Bendov of Dielectric has questioned the noise figures used by the FCC and in particular the wisdom of ignoring galactic noise sources that are prevalent at VHF.

In a talk I heard by Browne in Canada about 1997, he was the first to raise the planning factor issues and was kind enough to copy many documents for me.

Charles Rhodes was the chief scientist at the ATSC test center in Charlotte, NC. He is concerned about the effects of mismatch between the antenna and receiver effecting the required carrier to noise ratio.

Wu and Bouchard are scientists from the Communications Research Centre in Ottowa who have given papers over the past 2 years about their extensive testing of receivers and reception conditions.

If this august group of scientists and engineers says there's a problem, then there's a problem.

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Investment Notes
(What follows are not recommendations of SBE Ch40)

One of the United States greatest exports over the last quarter century has been American jobs. We just don't manufacture merchandise. That's being done off shore or south of the border. We import $400 billion more than we export. That's possible in large part because foreign companies want to own dollars or U.S. businesses. A good portion of U.S. stocks and dept is in foreign portfolios. The yen is down. The euro is down. The Canadian dollar is way down. The peso is looking a little better. Only the dollar has been attractive over the long term. As long as others want to hold the dollar, we are subsidized by money that comes from elsewhere. If that ever changes and the bubble bursts, then the shortfall must be made up by domestic money that won't be available for other uses. That would cause a number of dominos to fall and would put us into a period of great turmoil. This is just one of the reasons I don't expect the train to keep going down the same track. I don't know when or if this will happen. Change in general catches many mutual funds and investment advisors like a deer in the headlights. They follow the consensus and when there isn't one, they rarely have a plan B in the drawer. It's a time like all times. Take in what information you can. Read the financial papers and magazines. When some gray haired investment writer who was written off as being out of date ventures an opinion, listen up. He's seen more cycles than you have.