I was going through some old PMG photos and found a photo of this power meter reading.
It must be from the Brown Boveri, 250kW transmitter.

There were three transmitters installed in the old NASA building.
• VLK, Brown Boveri, 250kW (1975)
• VLM, 300kW Thomson (1984)
• VLL, 100kW Harris. (1976)
It was built as a temporary station after Cyclone Tracy destroyed Cox Peninsula, Darwin in 1974.
It was closed in July 1996. The 250kW and 100kW were scrapped and the 300kW moved back to Darwin as VLT.

Here is the proposed coverage footprint.

Hi I wish I had taken photos like that of systems I was involved with!
At the time a panel like that just showed normal readings that may have been logged in a journal and just indicated "all good".

The engineer in me does a mental sum 1300v at 30 amp is about 590kw the forward power is about 230kw does that mean the overall efficiency Pin / Pout is about 46%?

That's just the sort of thing you do when you walk past a panel with meters.
Nowadays there would be 28" TFT or whatever screen with every function from soil acidity to antenna temperature displayed in 13 different colours but nothing appeals to me than a bank of good old needle pointers that are sitting in the normal zone!

Fred.

There was a lot of work done on AM modulation: Some early AM transmitters were rather inefficient 150KWin for 100KW out was one I saw ages ago.& I have heard of 33% losses.

I think RA was at around 85% before they closed it & are selling it for a horse paddock. Same consideration as destroying the historic 2C0 site & probably selling the the Alexanderson antenna for Beer money.

Marc

Nice shots. Love the map.

Here are photos of the antenna array.
It used electric winches for lowering or raising the array for maintenance or when a cyclone was approaching.