Please Help with LNB / Feed Assembly / DMX241 or Original? - On the roof now...

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I'm beginning to think my true south was not alligned and my skew is off. I went back up and turned the mount east trying to adjust from 103W to 75W. How much rotation would you guess that is on a 3.5" diameter pole? I am still not scanning in anything...
 
I verified my 0 degree mark on the LNB is vertical when the dish is at the APEX. I rotated the mount to the east and I still only get TVBB 1 on 61W... I'm thinking I have a bad LNB or something... Does it matter if the LNB is upside down (0 degree mark at the top)?
 
signal.quest,
Hope this attachment goes through. When I adjusted the skew on this 7 1/2 foot, I aligned the dish to my true south, then marked the "0" skew marking and noted where it would be at the 12:00 noon position, removed the upper actuator bolt and lowered dish so I coul put it at the correct position. Hope this may help.
 

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signal.quest,
Hope this attachment goes through. When I adjusted the skew on this 7 1/2 foot, I aligned the dish to my true south, then marked the "0" skew marking and noted where it would be at the 12:00 noon position, removed the upper actuator bolt and lowered dish so I coul put it at the correct position. Hope this may help.

Thanks. I think this is how I have my LNB skewed. The 0 degree is at 12:00. Still only get a couple of TP's across the entire ARC... Driving me crazy at this point...
 
I think that lnbf should have the 0 mark 90 degrees from vertical. It will still work, but all your polarity's will be opposite. H for V, V for H. see attached pic for initial set-up of the polar mount when the dish is at zenith(apex). When at apex then, rotate the whole mount on the pole for peak signal. And adjust the elevation for peak. Then move the dish, with the actuator, east or west and adjust the azimuth ONLY for peak. When you have peaked at the end, move dish back to zenith, with the actuator, and recheck signal, re-adjust elevation for peak.
(should only be a small re0adjustment)
 

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I think that lnbf should have the 0 mark 90 degrees from vertical. It will still work, but all your polarity's will be opposite. H for V, V for H. see attached pic for initial set-up of the polar mount when the dish is at zenith(apex). When at apex then, rotate the whole mount on the pole for peak signal. And adjust the elevation for peak. Then move the dish, with the actuator, east or west and adjust the azimuth ONLY for peak. When you have peaked at the end, move dish back to zenith, with the actuator, and recheck signal, re-adjust elevation for peak.
(should only be a small re0adjustment)

So, at the zenith the 0 degree mark should be horizontal? I can see that 1 of the 3 TP's I get from Blindscanning is V, but TheList has it as H. Maybe my skew is screwing me up... I can't wait to get this all working - it is getting too cold to be on the roof!!! :)
 
First thing I will try tomorrow AM is to rotate the LNB 90 degrees.

I have another question that is not as urgent, but I will ask anyway. I don't have the actuator sensor wires connected, yet. I have a G-BOX with 2 sensor connections and my actuator has a blue, brown, yellow, and braided wire. How should I connect these? My searches have turned up that I might need to supply voltage apart from the G-Box?
 
Best to open up the actuator and look to see what wires are used. If three are used, it might have a "hall effect transistor" sensor. Look for a little black plastic thingy with 3 leads. If that's the case, I believe you'll have to change it out with a "reed Switch" which will work with the GBox. uses only 2 wires. The reed switch is usually just a small glass tube with a connection on either end.
 
Ok, another day if failure... But, I think I ruled out a bunch of stuff, I swapped the coax, and the LNB, with no improvement. I also tried rotating the LNB by varying degrees with no improvement. I tried adjusting the FD with no improvement. I either have a big allignment problem, or my receiver is bad. I have to figure this out already...
 
Someone suggested I use an anolog receiver for tuning. Do you agree? I have one that I can use. Do they blindscan? Are there enough analog TP's to use that technique?
 
Well, it's not really blind scan. Some can cycle thru the channels in a tune up mode, analog was 1 channel per transponder. so most C band sats had 24 channels. 12 vertical and 12 horizontal. Some have a signal strength meter also. I think Iceberg posted a list of what analogs are still up recently. Since your meter responds. I'm thinking receiver is bad. You should be able to get the dish to track with just the meter, good enough for normal C band.(previous post- don't know if it would be good enough for S2 sigs, but should be.) Then I'd try another fta receiver with the new LNBF.
 
Would it be a bad idea to try to hit the analog SATs without knowing if I can hit my true south SAT? The only TP's I have ever scanned were on 61 and 103. My true south would be 72 or 75.
 
Well, you have to get the true south( or as close as possible ) first, to set the elevation properly. Without the elevation set, adjusting the azimuth would be a waste of time, as there is no south elevation reference.
72W has DVB-S @ 3995 V 2220. Think this one may be S2- 3935 V 2823 I can't tell, openbox.
Try this, plug in your location and AMC6 at Satellite Finder / Dish Pointing Calculator with Google Maps | DishPointer.com . Zoom in and take note of some landmark the line crosses. At the dish, eyeball the landmark and dish center. Should be a no brainer if you are behind the dish. Peak your signal meter with the elevation adjustment. Then, move off of zenith and adjust azimuth as you move further from zenith. Even with analog, you have to set the elevation at zenith first. Your meter is the same meter that's in an analog receiver. If you can only see a few TP's, I put a buck on the receiver being bad.
 
I have not adjusted my elevation, yet - since I assumed it was good from the house up the street. Maybe it wasn't...

How many clicks of the G-Box represents a degree? Basically how often should I hear the meter spike when moving the actuator?

How much forgiveness is there in the azimuth alignment if it does not matter if I choses 72W or 75W as my true south? I noticed I was hitting the same SATs when I changed my azimuth -- just on different actuator locations...
 
Good news - I hit 87W, 91W, and 99W w/o adjusting anything. Just reading the meter more carefully.

Can I choose to center my APEX on 97W or 99W? That would center me between 58 and 137. Or is that bad practice? The reason I ask is I want to keep my actuator able to pull in so I can access the feed assembly from the roof.
 
I have not adjusted my elevation, yet - since I assumed it was good from the house up the street. Maybe it wasn't...
Can't hurt to check things as in: do you know it was set up properly before? I would rather not assume.
How many clicks of the G-Box represents a degree? Basically how often should I hear the meter spike when moving the actuator?
That would all depend on the actuators pulses per inch and the geometry of the mount. # of pulses changes some as the dish is moved from center to the ends, as the geometry changes.
How much forgiveness is there in the azimuth alignment if it does not matter if I choses 72W or 75W as my true south?
Near zenith, the azimuth is not all that important. But at the end of the arc, there's actually very little. But if you notice, around zenith, the actuator moves the dish left and right. Therefore WE adjust elevation. At the end of the arc, the actuator moves the dish more up and down, and WE adjust left/right. You can't properly adjust azimuth, until the elevation is correct. The Gbox numbers don't mean a thing until it's tracking properly.
 
Should adjust elevation as close to true south as possible, 97 is quite a ways from 74, Should shoot for something within 5 degrees, 10 max, as inaccuracies add up.
 
I measure my actuator length from the hardware limit to be around 20" and from the end of the arm to be 16". Since this acuator is old and most likely does not have a reed switch should I buy a 36" actuator like Sadoun sells? I really want to see as many SATs and still reach the feed assembly.
 
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