Rebuilding an FM Broadcast Station

 I thought I would share a little project that I was just involved with.  I have several photos of the progression of moving a broadcast station from the basement of an aging house into a new building on the same site.

The old house that used to house the studios and transmitters was getting in bad shape and the station owners decided it was time to make a move into a new building.

We had to dismantle the station from its 15+yr home and extricate it from the basement.

This is the BE FM 2C backup transmitter.  I didn't get a photo of the FM 4C coming out.

 

 Below is the old "ice bridge
", if it can be called that, that carried the cables to the tower.  You can see the new building and icebridge in the background.

 

 

 

 

The antenna switch.

Have you ever bolted the flanges of your feed lines together?

That is rigid 50 ohm line from the transmitter to the switch.

 

The 90 degree fitting going on the switch.

The gray box behind the switch is the 3kw oil filled dummy load.

When the system is up and running, each transmitter is always connected to either the dummy load or the antenna. The switch is electromechanical so it can be remotely controlled via the internet and the transmitters can be switched over.

 

 

The new location required all the transmission lines from the tower to be shortened.Here are photos of me changing out the connector.

An air fitting can be seen on the main body just left of the flange that allows air or other inert gas to be injected into the line to keep moisture out.  This particular installation uses a dehumidifier compressor to run dry air into the line.

 

Just strip back the outer jacket.

 

Clean the outer conductor with some sandpaper or steel wool.

 

Install the rear collar onto the line.

I did not get any photos of the rest of the connector going together.  Someone may have interrupted or I just got in the zone and didn't think about taking those photos, sorry.

Here is the connector happily in place on the fitting to the antenna switch.

Below are just photos of the rest of the installation.

 

This is the surge suppressor for the line feeding the main transmitter. 

 

Our initial test into the dummy load.  Yes, that is 4kw into the 3kw dummy load.  The transmitter will do 5kw, but let's not push our luck right.

I hope you enjoyed the photos.