By Newcomb Weisenberger

A Virtual Tour of KFI Engineering

(From 1933 – 2005)

This KFI Engineer’s ’walk’ is interactive, in that one may visit these sites in any order. One may walk as slowly as he chooses, may even stop to rest.

Pat Bishop

Don Wilson

Bob Kerr

Our narrator is Bob Kerr.

The Story Tellers are NBC’s, Ken Carpenter and Don Wilson with KFI News Anchor, Pat Bishop. The pictures are from my KFI file of digitized slides. Sounds were tape recorded on site. ( Sounds heard by engineers. Not sounds usually heard by the radio listener.)

Here, following are the bits and pieces. ( The gentle reader will provide the continuity as he moves about the site.) I choose to open the picture before selecting the sound.

Bob Kerr describes Studio A: Listen


The Story of the NBC Chimes: Listen


50-W Bread Board Transmitter: Listen


Story of KFI AUDIO "SWEEP" TESTS: Listen


THE 1932 5,000-w W.E. TRANSMITTER Motor/Generator: Listen


50,000 Watt Generator Room: Listen


The RCA 50,000 Watt Transmitter Room: Listen


A "SINGING ARC" drawn from THE 750 ft TOWER’s BASE, Reproduces Audio: Listen


KFI News Room Teletype Machines: Listen


Story of the KFI Rotunda and the Psalm Inscribed There: Listen


KFI Studios at Night - End Credits and "Good Night" Listen

(This building has since been demolished.)

Now, Some Engineering Notes about KFI

* The 5,000-w KFI Transmitter was installed in the Packard Building, 10th and Hope Sts. L.A.

* The 50,000-w KFI Transmitter and its 750 ft. tower were installed at Buena Park, Cal.

* A staff of some 25 KFI Radio Engineers manned these sites with three shifts 24/7. Chief Engineers were assigned, separately, to KFI AM, KFI FM and KFI TV.

* Every seven days each transmitter connection was inspected, cleaned and secured as needed. HV, Oil filled, switches were exposed for inspection and contact service.

* Every insulator was cleaned including the one at the tower base. (High Voltage creates a tension that attracts dust particles.)

* Duplicate rotating machines for, Filament, Bias and water-cooling pumps & tanks were alternated to operate every other week. These were inspected, and rotating bearings and rotating commutators were serviced.

Audio mixers for each studio and recording room were serviced too. Each microphone fader was kept spotless. Each double audio patch cord contact was polished and the rack mounted, patch fields* were cleaned

*This chain of mikes, preamps, faders, audio amps, compressors, reverb etc. was made so as to be completely flexible. These were automatic connectors that patch cords operated to substitute any element for any service. There were parallel audio chains for each mike, from each studio.

* Through the 50’s, transcription play back needles were changed every 15 minutes. (One needle for each transcription.)

* Some things, like air filters and the exercise of all distilled water valves, were serviced only during fifth week months.

* A log was kept that listed the initials of the engineer, the service done and when it was done.

* Testing of transmitter tubes, including new ones, was done in the 50-kw transmitter, during off-air maintenance schedules

* There were other engineering tasks not on posted schedules. Often I was assigned to re set-clocks, to the second! There were dozens of clocks in the operating areas. The studios, mixers and recording room clocks’ settings were very important to each other and to remain in sync with the NBC Red & Blue networks.

* The studio Engineer was programmed in 15 minute increments all through his shift. Perhaps his most important duty was to be in the right place at the right time, all day.

* The transmitter engineer kept a 30-minute log and a two-hour log. The 30 min log was for the FCC. They were very interested in the exact power being radiated, its exact frequency, and that a licensed engineer was there to make it happen. The two-hour log was for the station. There were two pages of entries, one up stairs and one down. This was an inspection of the total station.

* Sounds, visual checks and warning odors are noted. Each bearing is touched for its temperature and vibration. Listened to for sounds, good and bad. Commutators are cleaned and the contact brushes are pushed down to seat properly.

* We looked for water leaks and for hot stuffing boxes on the pump shafts. These are water lubricated. Here, a water seep is expected. Cooling water PH was monitored.

On the Importance of Operational Engineering Sounds

* As you listen to the sounds from these pages, you are hearing what the engineer wants to hear. These are the normal sounds that tell us that everything is doing its job and feels fine doing it.

* If the tower lights were flashing, and the station was off the air, we would hear the pounding of the contactor for the flashing circuit. It echoes in the large room. A small motor turns a cam that tilts a mercury capsule. This switch is on while the liquid laps over two contacts. The mercury flashes when contact is made.

* As we watch, it goes through a period of several flashes when it switches at a time of no voltage in the 60 cycle of the power. Slowly the cam slips away from the sync and the flash of the switch brightens at the point of full voltage again. The mechanical contactor slams shut each time the tower lights flash. It changes the pounding as the power cycles 60 times per second. So, through the quiet night of maintenance, we hear the pounding song echoing through the silent machines.

* From the time of its erection, the tower is lighted from ‘dusk to dawn’ every night whether KFI is on the air or not. The engineer counts the red lights at each level of the tower. When all the lights at any level are out, the Air Port tower will be notified and the whole KFI tower will be professionally, re-lamped. Including the top 750 foot beacon

It's Different Today

* Today, No one walks this walk, sees these things or hears these sounds, except for here on this site. Important changes in equipment and conditions have ended the experiences we have just shared. The engineer is gone! The rotating machinery is gone. The heat and the cooling water are gone too.

* Instead of the two floors of equipment, today’s 50,000-W transmitter can fit in one very small room. It runs cool and efficiently on house voltage! The 17,000Volt dc rectifier is gone.

* It is less expensive to buy a second, spare transmitter than to hire some one to fix it (When parts fail.)

* Instead of the expensive, intensive care that kept the old KFI alive, there is a visiting ‘doctor of radio’ who makes house calls on a cluster of stations.

* In recent years, we see continuing change. (Happening now.) Stations are disconnecting their program lines from transmitters and are feeding web sites instead.

* What will disappear, are the call letters, towers, the frequencies, the transmitters and the Engineers .who manned them. (Not long ago the 640kc frequency sold for over $15 mil.) We may live to see it abandoned!

* I live in ‘line of sight’ of the LA TV antennae cluster on Mt. Wilson, but we use no antenna.

* If all the TV stations left the air forever, it wouldn’t make any difference, to the City or to me...

----------------------------BECAUSE ---------------------------------

* We are, now, laced together with optic cable, (glass) across the nation and around and around the world! Not to mention signals directed back from space!

* 10 Millions of former listeners to 50,000-watt radio stations like KFI, are hand carrying mini transmitters with a gross Radio Frequency wattage several times all the old flame throwers combined.

* I have touched, heard, seen and worked with these things in the KFI places shown on these pages, beginning in 1947 and during the 33 years that followed. These places now exist only as these memories, that I am pleased to share with you.

Newcomb Weisenberger


Posted and Edited by Steve Blodgett - http://earthsignals.com