Cushcraft Satellite Antenna Array

This antenna works great, with my homebrewed array I had trouble receiving and a little trouble getting into the SO-41 satellite. Now with this antenna setup, transmitting is not a problem on any FM bird I've tried to work. I run anywhere from 10 to 45 watts to the VHF side with RHCP, which works fine and can be switched to LHCP. Soon after relays are added, I hope to make it able to switch between RHCP, LHCP, Vertical and Horizontal Polarization with the coaxial relay. I just added a UHF preamp to the 50 foot of coax, it's an amazing change on the receive side. The preamp was a kit for 9 bucks: http://www.hobbytron.net/R-PR-40, I have it in an aluminum box with two SO-239 connectors and a LED to show when it's on.

 

Here's a close-up of the rotors, which is the old AR-22 doing the azimuth and an Alliance U-100 for elevation and the fiberglass boom.

 

Here's the "Satellite Shack", nothing fancy. I'm using Nova to track, Radio is a Yaesu 847, and then two rotor controls that I track with manually. I also just added the FT847 Super Control, which's has a lot of cool features like: automatic Doppler correction for satellites and with this program the 847 is now ready for Full Duplex Cross Band Repeat!! There are a lot of other cool features this program offers, you can check it out at www.supercontrol.de and download the program for the Ft-847.

Computer Interface that is required to run the program.

All the interface requires is a Null Modem Cable, which I made my own for about 5 bucks (I would recommend doing this, very easy).  I purchased all the needed materials at Radio Shack: 

Now the wiring for the Null Modem Cable: Take conductor 1 (white) and solder it to pin number 2 on one of the 9 position female ends and then to pin number 3 on the other 9 position female end (the ends are numbered so you shouldn't have a problem finding the right pins). Now take conductor 2 (black) and solder to pin 3 on the first 9 position female end, then solder to pin 2 on the second 9 position female end. Last is taking the shielding and soldering it to pin 5 on each 9 position female end. 

Null-Modem Pinouts
DB-9 to DB-9

1 and 6

to

4

2

to

3

3

to

2

4

to

1 and 6

5

to

5

7

to

8

8

to

7

 

Pin Assignments
DB-9
1 Data Carrier Detect (Not Used)
2 Receive Data
3 Transmit Data
4 Data Terminal Ready (Not Used)
5 Signal Ground
6 Data Set Ready (Not Used)
7 Request to Send (Not Used)
8 Clear to Send (Not Used)
9 Ring Indicator (Not Used)

All the Null Modem means is switching a couple of wires, which we did with the first and second conductors. The Yaesu 847 only needs the three conductors to communicate back and forth with the computer program; transmit, receive and ground. All that's left is plugging the cable into the radio and computers serial port and installing the software.

 

If you have any questions on this please feel free to email me at: N0YK@amsat.org