Welcome to inside the Efland Site
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Download times use assumed connection speed of 33kbs
(100K, 30 seconds)
The outside once again
(62K, 19 seconds)
Welcome to the inside
(67K, 20 seconds)
There are three rack units with the repeaters
(65K, 19 seconds)
From the rear, you see a spare set of 2M cans in the forground, and the 6M cans in the background just behind the 6M machine.
(70K, 21 seconds)
From the front, the 6M machine shows the Mitrek dec, the 5K controller just below it, and a home made 6M 110W PA deck on the shelf above it. Next time, I'll use more heatsink and less fans. It's nice to have everything so that fan failure is not a problem, and this is not the case here. You can see the big cans behind the machine.
(66K, 20 seconds)
Below the 6M machine is the 220 machine. The 28V PA deck is on top, a set of themostatically controlled fans are below that. The 5K controller below that. Then we have the only non-Mitrek RF deck. This deck is built from two ICOM 901 modules, with an FPGA that spits in the right frequencies on power up and some analog stuff to make the levels and controls the same as the Mitreks at the connector level. Below the deck is a 220 bandpass filter. All the machines have band pass filters between the cans and the antennas.
(82K, 25 seconds)
In the center rack, we have the 440 machine. BPF at the top, the cans, then the PA deck, it's fans, the RF deck with controller. This controller also connects to three link radios.
(89K, 27 seconds)
The rear view of the 440 machine. There is an aditional cavity on both the input and the output. Just couldn't get full quieting no desense without them. Note also the perminante in line forward and reverse metering, and an RF sampler. This allows measurements to be made without changing the length of any of the lines. It also promotes occasional check ups, since all you have to do is plug in a meter set to see the forward and reverse power. Forward slug is 250W, reverse is 10W.
(91K, 27 seconds)
Below the 440 machjine are the three link radios to Research Triangle Park, Graham, and Greensboro. The link to RTP has a BPF on it. The BPF at the top of the picture is for the 2M machine in the next rack over.
(85K, 26 seconds)
From the front, the link radios stack up like wood. The fans were added at the bottom because it takes more power to run to RTP, the biggest hop in the system terrain wise. While most link radios run 5W, RTP link runs 20W. The link antennas are 10 dB vertical beams. To the left, in the 3rd rack, we see the 2M cavities and RF deck
(80K, 24 seconds)
The 2M machine uses a 6 cavity set. The RF deck is a Mitrek with the audio switching board used for audio delay. There is a spare deck stored here too. Above the decks is the SCOM 5K controller.
(84K, 25 seconds)
From the rear we see the 2M cans, decks, etc. as well as a good view of some of the other machines. A bit messy, but loose coaxes don't couple like a neat set all tied down next to each other.
(55K, 17 seconds)
2500 pounds of batteries supply the 28 volts to run the site. Dual 50A chargers add to the redundancy The lights for the building are both 120 and 24V, so even in an outage you can see. The 440 machine draws about 20 amps at 28V (including links). While the 28V has been a pain to work with, the efficiency (vs. 12 volts) is great. The site should run for about 2 days with no power.
(51K, 15 seconds)
Be sure to turn out the lights on the way out! Note junction boxes below the light switch for the DC lights.
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