DH Satellite 1PC or 4PC 3m, 3.7m, & 3.8m 48 Polar/Fixed Mount - Manual (Page 10)

FINE TUNING THE ANTENNA
Plan to take an extra hour of your time to get the most from your antenna. We recommend using a Spectrum Analyzer to do this or A1
Turbo S2 made by Applied Instruments.
With each adjustment you make you will be able to see your increase/decrease in gain. To begin you must string the antenna. This is
done by simply taking a string, tying it to one brace and running the string across the front of the antenna to the other brace at 180 degrees
and tying it so it is taut. Now tie another string to a brace 90 degrees from the first brace and running it to the corresponding brace 180
degrees away. Be sure you put the string on top or under the other string so as to not touch each other. When done you should have two
strings at 90 degrees and they should meet in the center of the antenna. (Ideally you should use four strings at approximately 45 deg.
apart.) If the strings don't touch at the center, then you will have to do some adjusting with the braces. Be sure your strings are taut. Stand
back about 30 ' and sight the antenna again and see where you must apply pressure with the braces or relieve the pressure from an area.
Now go ahead and make small adjustments with the braces, each time checking with the Spectrum analyzer to see that you are increasing
the gain of the antenna (See also page 7A).
PREPARING THE FEED ASSEMBLY
You will find below the focal lengths and focal length/diameter ratios for our commercial 3M, 3.7M & 3.8M antennas. This information
is necessary to set the antenna and feed up properly. Measuring the f/l
10' (3m) 36"f/l .3 f/d 12’ (3.7m) 57.6”f/l .4 f/d 12’5” (3.8m) 57.6”f/l .378f/d
Below you will find a list of feed collars that are available to purchase from DH Satellite. (See Fig #1 - #4) Your DH representative
should have asked you what type feed you will be using. We need this information to be assured we are sending the proper collar to attach
your feed to our struts. Take the collar and set it on the back of the scaler ring of the feed horn. Turn it until all three holes line up
between the two and insert the 1/4 "x 3/4" bolts thru the scaler ring and then thru the collar. Fasten with the 1/4" nuts. Most C-band and
dual feeds have a 3-bolt pattern on the scaler just for this. Now, slide the end of the strut thru the feed bracket as shown in drawing #1 and
attach each leg w/ 2-¼” x 1 1/2” bolt & nut. Do this on all four struts. Refer to Fig.#5. Place the flattened end of the struts onto the
antenna and use the 1/2” x 3" bolts to fasten to the dish. Use every other hole. Check to see the feed is at the focal length, and then
tighten all bolts. The actual focal length should be 1/4" inside the waveguide for C-band.
C14FHD COLLAR
& STRUTS
C14F COLLAR
& STRUTS
Fig. #2 Fig. #3 Fig. #4
35 ¾” OR 57 3/8”
DH Collars

C14F (Chaparral collar with conduit struts): C Band

C14FHD (Chaparral collar with heavy duty struts): C Band, C/Ku

C24HD (Seavey collar with heavy duty struts): C Band, C/Ku

KU4FL: Ku Band ONLY
Fig. #1
KU4FL COLLAR
& STRUTS
Page 6
Refer to the drawing on page 6A for the bolt placement of a C14FHD or C24HD.
1/2" x 3” Bolt
1/4” x 1 1/2” Bolt Collar
1/4” Lock Washers & Nuts
1/2” Rubber Washer
Antenna Surface
1/2” Steel Washer
1/2” Nut
C24HD COLLAR
& STRUTS
SPECIAL NOTE: Fig. #1 & #3 are used primarily with Chaparral and ADL C band and C/Ku band feed horns. Fig#3 is a special
order Heavy Duty feed strut system and may be purchased at an additional cost.
Figure#4: Our C24HD is a special order Heavy Duty system set up for Seavey manufactured C & C/Ku band feeds. This may be
purchased at an additional cost.
Fig. #5 C14F
Conduit Feed Strut