RTN

[Swamp_Rat]

Is RTN really that weak? I can get it on my 1m ku but the 1.8m prime focus won't pick it up.
I have 93-95% sq on the color bar channel on 83w but it doesn't come up with RTN. I tried to manually enter the transponder and it shows no sq.
What gives?

Thanks

 

[turbosat]

Maybe your lnbf needs some tweaking--focal distance, etc or skew? You'd think if the 1m does it a bigger dish should, but the bigger one might not be so accurate as the small dish....

 

[Swamp_Rat]

That is the only thing I can think of. What do you think, most likely the be distance or will a fraction of a degree on the skew kill it? I mean that AMC9/3 channel is smoking hot.

 

[truckracer]

It's funny, I have a 7.5' and a 10' dish.
My 10 will pull in stuff my 7.5' macroblocks and the 7.5' gets higher quality readings on g23 than my 10'.

 

[Lak7]

I could not get it at first, everything else came in OK, just not the RTN.
My Declination was off just a touch.

 

[Mr Tony]

RTN seems to have issues with bigger mesh dishes. The solid ones there havent been many issues

 

[turbosat]

Swamprat check that your feedhorn is centered as exactly as you can get it, then check the focal distance. Helps to have a tv 'rat' there at the dish, of course to see how adjustments affect it. There's a calculation someplace, to determine the F/d for any dish, D-squared divided by
16 x the depth of the dish. The first D is Diameter of dish squared. If you can find that geo-orbit web page it's got the formula on it, I think that is it though. Just run a string across the dish face, then measure frm it to the center of dish to get depth.

 

[starman345]

I think you nailed the forumla Turbo, here is the page anyway, lots of other neat stuff there too:

Footprints by Dish Size - Adjusting the Polar Mount for Prime Focus Antenna - C/Ku-Band Satellite Systems - Tuning, Tracking, Azimuth, Elevation, Declination Angles, F/D Ratio, Focal Distance, Inclinometer, LNB/Feedhorn Assembly, Actuator Assembly, C

 

[guapoharry]

Swamp_Rat, what kind of LNBF is it?

 

[Swamp_Rat]

I guess I should have everything listed like everyone else does in my signature.
I have the 1.8m Fortec solid, BSC621 lnbf and a Pansat 3500.
According to the manufacturer the f/d is 68.5 and the distance the feedhorn sticks out of the scalar is .52 inches.
I assume I can use the published specs or do I still need to calculate the distances?

Thanks for all the help.

Marty