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L.A. City Civil Defense in the 1960's

Created by Paul Signorelli, W0RW on 2022-04-09
L.A. City Civil Defense in the 1960's



Watching those poor Ukrainian people huddling in bomb shelters in Kiev brought back many war memories for me.

My first experience with Civil Defense was when an Air Raid Warden came to our house in Hollywood, California, and asked us to pull our shades down for a blackout. That was in the 1940's. The City (Los Angeles) had some recent experience with air raids, https://en.wikipedia.org/wiki/Battle_of_Los_Angeles

I lived about 1 mile from the Hollywood Bowl. We used to play in this big old dug out hole next door that was really a bomb shelter, but the adults never told us that.

After I got my ham license and Gonset Communicator, I joined the Los Angeles City Civil Defense (Civil Defense was what we now call 'Emergency Management') and became the Chief of RACES (Radio Amateur Civil Emergency Service) which was established in the FCC Rules, Part 97.407. It was the replacement for the WW2 War Emergency Radio Service, https://en.wikipedia.org/wiki/War_Emergency_Radio_Service.

 

 

 

 


My job was to train Hams and other communication people how to operate on the RACES radio net. We prepared a RACES Operating manual that taught radio and message handling operations.

The City had set up about 30 Yellow Gonset Communicators all over the city in shelters and Command Posts. There was one on the roof of the Roosevelt Hotel on Hollywood Blvd in an old Ground Observer shack. One at the Ft. MacArthur shore artillery bunker, etc. My job did not include installation or maintenance, that was done by the LAPD communications guys.

The Shelters were not bomb shelters but Fall Out Shelters for shielding people from radiation. They were stocked with water and CD biscuits.

The War preparation history, location of shelters, etc, is at
https://planning.lacity.org/odocument/77e1dad1-2431-4723-9dab-062eb4ff1081/5.8_Guidelines-MilitaryInstitutionsandActivities_1850-1980.pdf

We are still all targets.

The main 2 Meter operation used the K6MYK repeater, the first wide area AM VHF repeater in Los Angeles. This repeater was built by W6MEP, Art Gentry, (SK).
It was located at the Cities main communications site on Mt. Lee.

 



When LA City RACES needed to use the repeater, it could be switched over to the RACES frequency and identified as K6ROC. I was assigned to operate the repeater for the RACES Net every Monday night.

Mt. Lee (as it was known because of the old Don Lee Broadcasting Co), is really Mt. Hollywood because it has the 'Hollywood' sign on it and is at an elevation of 1700 feet. Sometimes, when it was really hot in the Valley, I had to go up early and 'check the radiation levels' in the swimming pool. They had a swimming pool on top for a 'Fire Water Reservoir'. You can see the layout of Mt. Lee at:
https://www.earlytelevision.org/w6xao.html

They had the RADiation Effects Facility (RADEF) Training there. The Training Officer would hide a little 'alpha' particle source there and we all had to plot the radiation levels on a map using a Giger counter and then zero in on the source. Just like transmitter hunting. The RADEF section had little trailers that contained all the Giger counters and several Motorola FHTRU walkie talkies.

The history of Mt Lee at: https://www.kcet.org/shows/lost-la/what-flattened-the-top-of-mt-lee-of-hollywood-sign-fame

There is an aerial picture of the building and the swimming pool, also a picture that shows the current facility. There is no building anymore, just a tower and many microwave dishes.

There is an article about the K6MYK repeater in QST, March 2004...p52, written by Bill Pasternak, WA6ITF. The K6MYK/K6ROC repeater would be used by all the hams in LA. Almost everyone had a Gonset Communicator. The LACD would give out free crystals to RACES Hams.

The Mt. Lee site was the main police receiver site and there was an LA Police Dept. had a CW circuit on 5 & 8 MHz that was used for cross country police stolen car reports, etc. Not sure why they still did this because there was TWX service all across the country. The LAPD operator controlled the entrance gate.

The other CD radios that were there in the command center were on every City frequency for disaster coordination. Most of the CD guys had commercial radios on the command channel where the Mayor and other higher up city officials could communicate.

The mountain top command center was built into the old Don Lee Broadcast booths and in a central pit with office cubicals in it. Each cubical had a unique GE radio remote control head. The top floor, looking down into the pit had a Master Control console that could operate any of the individual radios below. The main Emergency Operation Center (EOC) was at LAPD HQ's downtown and this was just a backup command center. There was also a hardened command center in an old WW2 bunker. All of the GE radios were in little gray boxes upstairs near the antennas. The roof was a porcupine of antennas. (There was a separate radio for each agency; e.g.: Water and Power, Red Cross, Police, Fire, Schools, CD, Public Works, etc.).

The LAPD had receivers on all 20+ mobile VHF frequencies and they were microwaved down to the downtown HQ on "The Link" to LAPD HQ's. LAPD dispatchers used 1730 kHz for their primary dispatching. All the cars listened to this frequency and each car transmitted back to his own dispatcher on separate VHF frequencies.

The main Mt. Lee radio tower and the building were torn down some years ago. It was originally a TV studio for Don Lee Broadcasting Co. Channel 5 (W6XYZ). The old W6XAO/W6XYZ guys didn't have any Studio to Transmitter microwave equipment so they put the TV studio right under the antenna.

After my LACD activity I joined the Red Cross. We had a dedicated group of guys (The 'Emergency Communications Corp' with a Communications Van) that joined the Red Cross and gave them top priority. So, we had a team of 10 guys that only worked for the Red Cross. We all took the Red Cross training, etc.

Paul, W0RW

 

W6LZY2022-07-05
L.A. City Civil Defense in the 1960's
Hello Paul. I remember well your conversations on my goodie bird.
I’ll never forget k6 chickens,hens&rosters.
Used to be K6jnh now W6lzy licensed since 01\55.
You brought back lots of fond memories.

73; Bob Hopkins W6LZY
KD8IIC2022-04-15
L.A. City Civil Defense in the 1960's
Excellent Work OM Paul! My maw and paw were in CD in Columbus Ohio during the tense Cuban Missile Crisis...
We'd been toast in an attack as there was the large North American Aviation plant within two miles of our home as well as the Defense Department's Huge Store Rooms/Warehouse known as "The Depot" by all the locals... Western Electric was another huge target of vital strategic wartime technical and manufacturing just a few more miles away...
W0RW2022-04-12
Re: L.A. City Civil Defense in the 1960's
Yes, There was a Mag Tape ID system on the front of the repeater. It was like a 35mm sprocket drive belt.
More details....
The original 420 MHz control system only had four basic functions using four supersonic tones in the region of 15 to 20 kHz. The original functions were:

1 Transmitter on
2 Transmitter off
3 Audio transfer
4 Squelch adjustment up and down

The control receiver was a very modified ASB-7 receiver. It was a wideband FM system, probably in the vicinity of 100 kHz deviation.
The 420 path to the control point was not very good as it had to shoot through Cahuenga pass, the higher peak just west of Mt. Lee. Later Art (W6MEP) added one or two pre-amplifier stages to the original ASB-7. The
pre-amp/s were built in to cavities from another piece of Military Surplus equipment that originally used light house tubes. Instead, Art used Nuvistors that had grid caps and plugged into the lines inside the cavities.

It was located in a room within a 8' x 8' room that had a glass window looking into the outer area room.
When you walked into the repeater's room there was only the sound of a few fans whirring. the receiver speaker was usually left turned down. If the repeater was in use, and it usually was, you could hear relays clicking from inside of it. When the ID would
start you would hear the 35mm mag film pick up speed and move. You could hear (clickity-clickity) of the silver shoes riding on the film and then the contacts falling into the various holes that were punched in the film for the Modulated tone CW ID. There were three sets of parallel holes. One was the K6MYK ID, another the K6ROC ID and the third was a single
hole to tell the loop to stop. There was a switch for switching between the K6MYK ID and the K6ROC ID.
The 35mm mag film strip was about a five foot loop. The Code consisted of holes punched using a
standard hand held paper punch. A dit was one hole, a dash was three holes and a space between a dit and dah was three spaces.
The drive for the film loop was an old turntable motor assembly with the shaft extended through the front panel to carry the 35mm drive sprocket.
There was also a Shure Bros. tape head that rode on one of the mag-strip tracks that contained Millie's (K6JJN) voice ID. When Art had to make a new ID track he had to take a tape recorder to the repeater and plug the ID tape head into the recorder in place of the recorder's normal head.

There was also one other unique sound that could be heard in the room. That was the sound of the audio transfer relay when it would move. It was a Ledex rotary selenoid. Every time it was pulsed it
would rotate a standard rotary switch one position - basically a SPST as a result of every other contact wired causing control each pulse to toggle the audio between the two-meter receiver and the 420 control link receiver.
Since it was all Vacuum Tubes, it was Rad Hard.
Paul w0rw
Reply to a comment by : KC6RWI on 2022-04-11

Looks like there is some sort of belted system on that repeater, the person is pointing to it??
Reply to a comment by : KC6RWI on 2022-04-11

Great article, I still go into Los Angeles for work.
KC6RWI2022-04-11
Re: L.A. City Civil Defense in the 1960's
Looks like there is some sort of belted system on that repeater, the person is pointing to it??
Reply to a comment by : KC6RWI on 2022-04-11

Great article, I still go into Los Angeles for work.
KC6RWI2022-04-11
L.A. City Civil Defense in the 1960's
Great article, I still go into Los Angeles for work.