C-Band with GeoSatPro 120cm Offset Antenna

lawdog71

SatelliteGuys Family
Original poster
Mar 5, 2021
73
51
utah
I started this project a little while back, but hadn't really been able to delve into it as I'm an OTR trucker. I can not acquire any bird. The pole is plumb, here are the particulars:

Antenna - GeoSatPro 120x135cm Offset dish
LNBF - C-band Titanium C1-PLL with Scaler
Motor - Technomate TM-2300M3
Receiver - X2 Premium IV
Location-
Latitude: 41.6932°
Longitude: -112.2955°
Nearest True South Bird: Eutalsat 113W (A) (aka Satmex 6)

1. Motor set for 42 latitude.
2. Dish elevation was set for 23.5 (no joy), then added 4.5 (per dish assembly instruction) and no joy

I got to be missing something (or somethings) very simple, any help be great appreciated.

~scott
 

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If you did the installation as carefully as you took the photos, I'll bet it's done well.

Aim for 99W. The 4040 H 26400 transponder is the easiest to receive with a small C-band dish. It's strong enough that I can remove the scalar and adjust only the LNBF for strongest signal. I then re-install the scalar and adjust it for strongest signal. The scalar will boost received signal.

The small dish has a wide beamwidth (2+ degrees). You don't need to aim the dish in azimuth so precisely for C-band in this case. Try different elevations since with a motor that's where you could have some error assuming all settings in the receiver are correct.

Added: If you're getting frustrated and can't find any signals at all, mark all settings so you can return everything later. Then loosen elevation adjustment only and physically pan the dish assembly up and down very slightly. I bet you can then find 99W if azimuth is roughly correct.

By the way, I've only ever received 2 transponders from 113W ever at different times with a small C-band dish, so don't spend too much effort trying to receive that satellite until you know everything is lined up correctly.
 
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I am a dumb@$$....I removed scaler when back inside and still no signal...I happen to look out the window and my darn cable to LNBF was hanging. I musta at some point not reconnected it. Able to get G16 xpnder 4040. Now gotta put scaler back on.
 
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I understand the picture isn't perfectly straight, but on image xxx00006, the LNBF doesn't look like its pointed to the center of the dish and the cable isn't connected. Glad you are able to get signal. I played around with a 1.2M Ku dish for C-band for a while before moving up but it was a lot of fun.
 
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I understand the picture isn't perfectly straight, but on image xxx00006, the LNBF doesn't look like its pointed to the center of the dish and the cable isn't connected. Glad you are able to get signal. I played around with a 1.2M Ku dish for C-band for a while before moving up but it was a lot of fun.
Yea were right the cable wasn't connected only figured that out as noted above.
 
The rim of the dish seems to have several dents. Is the dish face still flat? Do multiple string tests for that.

Dish elevation setting of 23.5 would be about OK; it should be bend angle of the motor shaft (30?) minus dish declination angle (above or just under 6 degrees, for 42N, depending on if you use the 'traditional' angles, or the (better!) modified angles).
What does worry me though is the question if the dish elevation scale is mounted correctly, it looks like with a higher elevation, the scale indicates a smaller number? Is that in fact the case?

LNB looks like it aims a bit high; it should be aimed lower than the center of the dish.

Greetz,
A33
 
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The rim of the dish seems to have several dents
Yea, while I was putting it up, had some winds and kept dropping bolts. Dropped it a couple times and thankfully was just the rim. I decided to use a couple long screwdrivers on the 3rd try thru a couple bolt holes and was finally able get it bolted down.
LNB looks like it aims a bit high; it should be aimed lower than the center of the dish.
I noticed that too when I went to reconnect coax.
 
If using a motor, you don't manually skew your LNBF. You set the LNBF at 0. The motor will skew the dish. But you do need to move the LNBF and scalar forwards and backwards for best signal.
That what I had thought too, but I read in a couple places that the 0deg on the LNBF scale needs to be parallel to pole (either up or down), once I did this signal strength increased and able to get more transponders on G16.

I am also getting transponders from G19 (while on G16), so tomorrow I'll adjust LNBF and scaler.
 
...the 0deg on the LNBF scale needs to be parallel to pole (either up or down), once I did this signal strength increased and able to get more transponders on G16.
I'm not with my LNBF now so I can't look at it to see if what you say is coincidentally correct. It sounds like that may be true provided the motor is at its 0 reference. This would not be true if the motor has moved away from its 0 reference.

I suspect it's another way of saying the 0 degree reference on the LNBF must be in line with the 0 reference mark on your LNB holder bracket. This is true regardless where the motor has turned.


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So I know I'm on 99W as I'm getting xpndr 4040, but I'm also getting a xpndr 4172 with about 60 audio channels including Naval Observatory Master Clock and NPR. I'm looked over Lyngsat and satbeams.com and cannot determine if this xpndr is on G16 or another bird near it.

Ideas?
 
Hey ya'll, thanks for your help. The weather worked in my favor today (last few days we've had high winds and snow), so I was able to finally fine tune and "button" things down.
I live in a "bowl" (mountains around me) in Northern Utah. I provided a support between my corner fence post and satty pole, hopefully that will help with any high winds.

Here is final pics of installation (other than I wanna shorten up and finalize cabling, but not until I can get a Ku LNB on it).

With that said, recommendations on installing Ku LNB?
 

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I installed an offset Ku LNB on my motorized mini-BUD. It worked OK. I would just motor as necessary to peak the signal on my Ku LNB. I could receive most Ku satellites. But...doing this, I could never receive LPB PBS on 87W or NBC on 103W Ku well.

I finally chose to remove the offset Ku LNB and just swap the entire C-band LNBF/scalar and its mounting bracket with the Ku-band LNB and its mounting bracket when I want to change between bands. I can do this in 2 minutes and then I get maximum performance on C-band or Ku band, just not at the same time.
 
Its always difficult to determine what is straight from a picture but your LNBF still looks off. Try this, point your dish at your true south satellite and take another picture in front of the dish