Got a 12 foot prime focus dish

[truckracer]

Hey guys, I landed a free 12 foot fiberglass c-band dish with polar mount and 36 von weiss actuator (hope i spelled that right).

The dish is on my cousin's property and he welcomed me to take it. It is composed of four fiberglass petals and has a buttonhook feed assembly with a feedhorn and lnb.

The lnb is pretty old and says its a 50 degree K (ouch!! way too hot) by today's standards. I have a new astrotel 20 degree lnbf for c-band.
I would imagine that the buttonhook will need guy wires to be secured precisely over the focal point which I can fabricate from some hardware store stuff.

This dish is very lightweight for something this big. I have not checked this dish to see if it is warped. I will check it monday. All of the bolts and nuts are terribly rusted so I am going to take my recipricating saw and dremel to cut out the rusty bolts. These things are really frozen in oxidation.

I cannot apply heat to the bolts because it may damage the fiberglass.

Is there anything I should look out for before I do all this work?
Is this fiberglass four piece dish worth the effort. It does take a 6 inch mounting pipe, my existing pipe is a 4 inch schedule 40 stainless steel filled to the top with concrete and planted four feet in the ground with a 24 " base. THis should be sufficient to hold this dish, it seems very lightweight, around 80 pounds or so. the fiberglass is somewhat thin. It does not have anything on it showing what brand or who the manufacturer is.

I will have ot make an adaptor for my pipe to work with this polar mount.
Let me know what you guys think.

 

[sattec]

12ft is over kill. its gonna eat motors/motor drives. dump the button hook and get four chomium rods from lowes with some L-brackets and bolt the rods to the edge of the dish and support the feed horn by bolting the rods with some adapter L-brackets to the NEW feed horn. the button hook may be very rusted at the bottom and needed to go. just like you were gonna guy wire the button hook, use the rods and never look back......... have fun!!

 

[truckracer]

thanks

I will definitely take your advice and dump the buttonhook, I have read nothing but bad things about this mounting style on older dishes. The chromium rods sound great maybe using some lockwashers and jam nuts to secure and adjust them in place.

 

[tdti1]

For C-band bigger is better, I am also looking for a 12' or 14.5' to put up next to my 10' because some birds I get come in weak over the Atlantic, I don't like button hook, but the guy wire will fix it from sagging, fiber glass dishes do not keep the inner mesh good for to long, and you may not get Ku-band, if you do it will be weak, but if you are lucky it will work good anyway try it out, hope you put your pole in a good spot, my dish goes from about AMC-8 to a bit passed NSS-806, though I need to tune it when I can because I need to push up on my dish to get a lock on many channels, grab a 4dtv and a dvb box with c/ku feedhorn and lnbs and you will have yourself a fullview system. Good luck.

 

[truckracer]

12 foot dish

I am planning on using this dish for c-band only, since it is a fairly old dish, I would have to think the mesh inside the fiberglass is "c-band only" and probably not compatible with KU. For KU reception I will continue to use my 90 cm patriot ptx offset with a .5 Ku lnbf and sg-2100 motor.

I was reading on some c-band pages that a c/ku feedhorn makes some reception compromises receiving both bands with a common feedhorn and you almost always get best reception on c-band with a c-band only lnbf (feedhorn, scalars, lnb all integrated into one unit). Plus you don't have the signal loss associated with the polorotor. I don't know how much difference we are talking but this was mentioned on some cable headend sites.

I am going to make sure the dish is not warped, and the focal point is centered and proper distance. Plus this thing has a polar mount and hopefully a functional 36" actuator. I am going to test it with 3 motorcycle batteries wired in a series with a 30 amp fuse inline. Wish me luck. This configuration should give me 36 volts dc. (12+12+12 in a series).