SM6FHZ 1296 MHz EME

The antenna for 1296 MHz EME is my 5.5 m dish with a f/D of 0.37.

I started with using the old W2IMU dual mode feed horn for 23 cm  EME. The dish is heavy under illuminated, but the antenna temperature is good with this feed. The gain is affected by at least 1 dB. Next step will be to look into making a more optimal feed for this dish on 23 cm.

Equipment on 23 cm EME:

The transmitter chain consists of an IC-756pro3  (I used my old, 1983 vintage, ICOM IC-751 before) driving a UHF-Units (SM6DJH) transverter followed by a NEL-1306 pre-driver to a 8907 driver. The power amplifier is a TH338 (or YD1277) in a OE9PMJ cavity. 

 23 cm TH338 cavity

Who said we were into "wireless"?

The 23 cm TH338 PA in the rack

Feeder loss is about 1.1 dB using 7 m of 1 1/4" foam heliax + 0.3 m of 1/2" super flex heliax + 6 m of 7/8" foam heliax + 1 m of 1/2" super flex heliax. I need to work more on the feeder loss.

The receiver chain starts with a Teledyne CS33S10 SMA-relay for protection. Preamplifier is a NE32584 in a G4DDK design. 

About 20 m of RG-213 cable run from the feed mounted pre-amp to a GIGATRONIX 3-pole interdigtal filter (40 MHz BW) into the transverter.

Measurements on 23 cm EME:

Presently I am getting 7.2 dB ground to cold sky noise with the dish at a -4 degree elevation angle. The ground to cold sky with the feed horn alone measures 7.7 dB, slightly more than with the dish. I interpret these results as my 25 years old W2IMU feed still have some resistive losses and need some more refreshing work done on it. This is good news, as the first round of refreshing actions made good improvement (from 6 dB to 7.7 dB of ground to cold sky noise with the feed horn alone) and when the second round of refreshing work has been done the complete system will hopefully be improved to a level I did not expect to be possible.

Sun to cold sky noise is presently more than 15.3 dB at a SFI of 71.

  23 cm ground noise on October 21, 2012

The above picture show the ground noise on 1296 MHz going from +40 deg elevation (the -69.5 dB noise value) down to -10 deg back up to +10 deg (noise values around -68 to -68.5 dB) and then moving the dish from Az=120 deg to Az =225 deg and ending with the service position at El=0 deg (noise value of -63.5 dB).

QSO's on 23 cm EME:

Operating 23 cm EME on October 9th, 2010 documented by SM6CKU.

SM6FHZ 1296 MHz EME initials list (2022-10-16), initials from 1984 to 1988 were worked from JO66EW with my old EME rig:

The background sound on this page is a recording made by IW2FZR, Dario,  in March 2009 on 23 cm EME. Thank you Dario.

Updated October 16th, 2022.              http://www.2ingandlin.se/SM6FHZ.htm