This is the Portable System, a 10368-144LP DEM Transverter and Qualcomm amplifier at about 900 milliwatts (foreground right).The system uses a DSS offset feed dish, so it looks like it is looking down when it is not! The "IF" rig is a Yaesu FT290RII seen to the left.
The DEM Transverter is on the left, in the center is the Qualcomm amplifier power supply with Xmit LED indicator and on the right the Qualcomm Amp. The rolled up mini-coax provides about a 7db 10Ghz attenuation between the DEM and the amplifier.
The original DSS feed is modified by first drilling the waveguide out to 3/4". Then a thin "wafer" of 3/4" diameter aluminum rod is cut for the short. The shorting plug is mounted on a 6-32 screw. The screw runs through a 6-32 nut soldered to a brass plate mounted where the original feed / pc board was mounted. The feed can then be adjusted for the best match. The SMA connector is mounted then where the .050" dia probe is about .390" from the short, at the mid point of the short's adjustment range. (.415" to the center of the probe.) The probe length is cut to where it projects .254" into the WG. Using these measurments, no adjustment should be required. 1KW ERP with over 30db gain measured, using the 18" DSS dish.
March 8, 2004 14:00Z, 100 Mile 10Ghz Contact
On the way to Minneapolis I stopped at EN36ch. The temperature was 15deg F with a slight breeze, but Gary WØGHZ in EN34lx was able to follow the thermal drift and I was successful working him on SSB with about S2/S3 signals. This was a path that starts across the now frozen Lake Milacs for about 20 miles, that I have been wanting to try for some time. Exactly 100 Miles to Gary's, no QSB and no precip enhancement. First "DX" with the new system.
KØAWU's 10Ghz Tower System
KØAWU's 10Ghz QualComm System
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