STONEHENGE TOWER SITE
(Formerly know as the KGON Tower)

Portland, OR

(Page under construction, but updated 8/7/11)

Pictures and captions by Kent Randles

Combined in the omni-directional "master" antenna:

90.7 KBOO 25,500 Watts
92.3 KGON 100,000 Watts
93.1 KRYP 1,550 Watts
93.9 KPDQ-FM 50,000 Watts
95.5 KXL-FM 100,000 Watts
97.1 KYCH 100,000 Watts
99.5 KWJJ 50,000 Watts
104.1 KFIS 6,900 Watts

On top of the tower in its own antenna:

94.7 KNRK (directional) 6,300 Watts

Under the first level of the tower:

107.1 K296FT 28 Watts

The tower is about 620' tall, on top of a 1000' hill.

I have tons of pictures of this site, just since the end of 2001.
I'm starting with the last station to be added, 93.1 KRYP.

Click on thumbnail pictures for 1024 X 768 versions

20060128_069_Shawn_tunes_up.jpg (243331 bytes) January 28, 2006

Shively's field service guy, Shawn, tunes up the WHOLE now-8-station combiner.

Each station has a "module" which keeps their signal from "mixing" with the other stations
and creating intermodulation products (and RF chaos).

20060128_070_KBOO_and_KFIS_Combiner_modules.jpg (225931 bytes) The KBOO combiner module in front, and the KFIS one behind it,
"branch" combined with the new KRYP module.
The big one to the right is for KXL-FM, which was the last high-power station added.
20060128_072_Branch.jpg (212685 bytes) Carefully engineered "branch" combiner point, cut to frequency at the Shively factory in Maine.
KBOO's on the left, KFIS's on the right, and the feed to the KRYP module leaving from the middle.
20060128_073_New_KTRO_Combiner_module.jpg (231249 bytes) New KRYP combiner module, of the new Shively "thin" style.

Output on the left, input on the right.

20060128_076_KTRO_combiner_wall_mounted.jpg (225906 bytes) There are 3 dB hybrid combiners on the inputs and outputs of the two filters.

MUCH bigger versions shown down the page for the higher power stations.

20060128_074_KTRO_joins_the_wideband_input.jpg (237431 bytes) The KRYP combiner module feeds the wideband input.
20060128_078_module_outputs.jpg (249094 bytes) As you can see, the feedline just keeps getting bigger as more stations with more power are added,
ending up with almost 170 kW into 9" line that goes all the way to the antenna.

Here, Shawn is "sweeping" each stations' input through the output to the antenna.

2002-04-18_Stonehenge_Combiner_Modules.jpg (226108 bytes) Here's a picture from 2002 showing the input sides of the big modules.
2002-07-08_004_9_inch_line.jpg (225029 bytes) Here's where the 9" line goes through the floor on its trip to the tower.
Note the size of the line compared to a phone book.
Handy_Landmark.jpg (219563 bytes) Oh.  THAT tower.
20060128_087_KTRO_Main_and_Backup_Xmtrs.jpg (231700 bytes) 93.1 KRYP Main and Backup exciters and transmitters...hey:  only 550 Watts TPO.
20060128_086_KTRO_Mini_Xfer_switch.jpg (237396 bytes) Possibly the world's cutest coaxial transfer switch in the upper left, for KRYP's 7/8" line.

Note the normal-sized switch for 3 1/8" line.

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