Thursday, October 1, 2015

Busy Day on the Iowa.....

Spent yesterday on the Iowa helping the Grey Radio Gang in getting some of the original receivers and a transmitter running for a crew tour of the radio spaces next week.

I won't be there as I'll be attending the 5th annual "Supras in Vegas" car show, so I wanted to make sure things were good-to-go.

Didn't work......

We started having receive antenna problems right away (the ships uses separate antennas for receive and transmit), so we never got around to getting the "Aft Twin Whip" transmit antenna connected using the adapter I made up.



The picture was taken before we connected the feed lines to the antennas from the box mounted between them. In the picture below you can see the feeds coiled up on the box:



The box contains a Jennings vacuum variable capacitor, and a length of copper strap used to "tune" the reactance of the antenna to a know value so the antenna couplers located in the transmitter room can work with it.

These antennas, made by a Canadian company, are rated for 10kW continuous duty, so they'll just be loafing along with 1200 Watts. The large feedline coming out of the right hand side of the box is 3-1/8" Andrew Heliax which runs down to the transmitter room. The cable terminates in a flange type connector (I forget the Andrew designation...), and I had to fabricate an adapter to a Type-N connector so we could use a jumper to the output of the coupler.

Back to the receivers....

At first we thought we had dead receivers, then we thought the couplers were bad, then it looked intermittent, then everything started working again. I was busy doing some mechanical "fine tuning" on the adapter (no hammers, just a file and a caliper!), so I wasn't helping with the receivers.

Anyway......the receivers appear to be operating normally, and the GRG will connect the transmitter to a dummy load, and talk to the Ham Radio station we already have aboard.

Not the best, but at least it will show the tour group that we can get audio from the Red Phones, through the Coke machine, down to transmitter room, and on the reverse path, audio from the receivers, back through the Coke Machine, and on to the same Red Phone for the demonstration.

2 comments:

  1. Thanks!

    Let me know if you'd like to see the ship, and I can meet you there and give you the tour.

    ReplyDelete

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