San Francisco
Roy Trumbull - Editor
Bill Dempster - Artist
Advertisers for this month's newsletter are:

Projection Systems Inc. - Marci Mearns - (510) 259-2469
Santucci Video Systems - Sandra Santucci - (818) 704-6324
Belden - Steve Lampen - (415) 440-8393
Media Technical Consulting - Paul T. Black - (925) 827-9511
MARCOM - Martin Jackson - (408) 768-8668
William F. Ruck, Jr. Broadcast Engineer - (415) 564-1450
Ross Marketing Associates - Kevin Frost - (408) 988-8111
Kathrein (Scala Division) - Michael Wm. Bach - (541) 779-6500
Hammett & Edison, Inc. - Dane E. Ericksen, P.E. - (707) 996-5200
Howell Communications - Mike Howell - (559) 674-8989
Econco - George Badger - 650-327-7599
Improbable Missions Fource - Mike Schweizer - (888) 4-ISDN4U
Digi-Gear / Cancomm - Eric Lane - (818) 980-9188
West Penn Wire/CDT - Michael J. La Porte - (650) 652-9080
Microwave Radio Communications - Clark Rhoads - (909) 246-1602

Babes/SBE Luncheon on Wednesday Sep 24th, 2003

This month Paul Marks is gathering together engineers who will tell us about their personal adventures in implementing IBOC on AM and FM transmitters.

It's tough to be at the leading edge of these things. I'm old enough to recall AM FM stereo (one channel per each transmitter) and quadraphonic sound (two channels on station A and two channels on station B). And then there was the RCA analog hi-def TV that broadcast side panel information using a second TV channel.

The area has hosted some interesting technology. For years KNBR did frequency shift keying of their carrier under control of the Navy to communicate with ships out in the Pacific.

When KRON-TV was getting set to broadcast DTV I was asked by a senior executive if the propagation would be better for digital than for analog TV. I told him it was like the law of hereditary birth control. If your parents didn't have any children, you won't have any children either.

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.

Falling Towers

As I noted a few months ago, a lot of towers have fallen during attempts to modify said towers for DTV. Recently the first information as to a suspected cause came out. It appears that the towers must have horizontal and diagonal support members strengthened to take a heavier load. In converting from one type of member to another, the tower is sufficiently weakened that it will suddenly collapse if the old support is hanging free while the new one is being put into place.

I'm no structural engineer, but I believe a guyed tower is just at the edge of cork screwing into the ground. A torsional failure in one section is all it takes.

Water Tunnels

I highly recommend the article City of Water in the Sept 1st issue of the New Yorker by David Grann. There are two water tunnels into Manhattan and they are ancient. Some think that even if you could get the brittle old values to work, that stopping the flow of water would cause many sections of the tunnels to collapse in on themselves. A new tunnel is being built deep beneath the streets but it has been stopped for political reasons (no money) several times and isn't slated to be complete until 2020. The men who build these tunnels are known as sandhogs and they have their own subterranean culture and fellowship. Each mile constructed has its own tale of death and maiming.

City governments manage to put off the most crucial tasks until disaster is only a matter of when, not if. San Francisco has put off needed repairs and modifications to the waterway that connects from Hetch Hechy in the Sierras to Crystal Springs. This is a major undertaking. Rather than budget money in a sensible incremental manner so the work could be ongoing, it has been kicked it under the rug for decades.

It's strictly a matter of fate as to whether New York City or San Francisco suffers a fatal loss of water supply first.

Check Out the Last Page

Bill Dempster is retired and has gotten back to painting again. He is quite talented and a year ago he said he was going to do our little man logo in oils. On the last page please take a look at the little man in color.

I went to the Mark Chagall exhibit at MOMA recently and I swear one of the really large paintings had the sort of people with which Dempster usually populates his paintings.

Solution to Ownership Rules

The fight between Congress and the FCC over how many stations can be owned by a monopoly has a simple solution. Let the monopoly own as many as they want but only one station per market will be entitled to "must carry" on the cable system.

Solomon figured that one out a long time ago.

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Web Page

Webmeister Tim Pozar has the current newsletter plus newsletters all the way back to 1996 at:

Roy also posts the current newsletter at but the posting is without links.