feed horn troubles

[rover54]

hi all i get even channels on 1 satellite but not odd channels the next 1 i move to ill get the odd channels but not the even im asuming its somthin on the dish? ive got some old lnbs laying around is there any way to test these off the dish also when you take the little square box off the lnb should the notch be vertical or horizontal when you put them on or dosent it matter? my lnbs are probly obsolete by todays standards dish is old anybody know who has best prices and whats a good number for a lnb? thanks in advance

 

[WyrTwister]

hi all i get even channels on 1 satellite but not odd channels the next 1 i move to ill get the odd channels but not the even im asuming its somthin on the dish? ive got some old lnbs laying around is there any way to test these off the dish also when you take the little square box off the lnb should the notch be vertical or horizontal when you put them on or dosent it matter? my lnbs are probly obsolete by todays standards dish is old anybody know who has best prices and whats a good number for a lnb? thanks in advance

Sounds like the little square box is not working ( polorotor ) . Check the wiring first . Since it sounds like you took it off , bring it inside & try connecting it directly to the receiver & see if it works .

As far as the LNB , depends a lot on how much money you wish to spend .

Wyr

 

[daveyhouse]

I would say your servo motor is bad. That will be a small plastic box on the back end of your feedhorn, with three small wires going to it. This actuates a probe in one direction for even channels and another direction for odd channels. You can get these fairly cheap off Ebay (new)
When you take it off notice the position on the feedhorn and make sure it does not move when you put the new on
If you are getting at least one even or one odd channel then your lnb is working.

 

[gizzer777]

That little blue box

hi all i get even channels on 1 satellite but not odd channels the next 1 i move to ill get the odd channels but not the even im asuming its somthin on the dish? ive got some old lnbs laying around is there any way to test these off the dish also when you take the little square box off the lnb should the notch be vertical or horizontal when you put them on or dosent it matter? my lnbs are probly obsolete by todays standards dish is old anybody know who has best prices and whats a good number for a lnb? thanks in advance

Yep...that little blue (Chapparal) box is a servo motor. They run about $20 and when they go give the symptom you describe. It is SEPARATE from the LNB's. Its sole purpose is to turn the polorator to V or H for different stations. Being locked onto either odd or even channels is a dead giveaway (or as you say, check wiring). I have only changed out 2 of those motors in over 20 years.

There used to be a Receiver (maybe the Toshiba) that allowed you to flip through either the odd or even channels while surfing to save wear and tear on it but they are sturdy little beasts....(I recommend getting the Chapparal)

3 wires, 2 screws and the replacement o ring that comes with a new one make replacement easy! Just did my second one in Dec. Do make sure to waterproof the wire connections and make sure the slot on the new motor lines up with the sensor inside the Co Rotor! Should be a 10 min job!

 

[rover54]

hey thanks for all the replys i havent taken that servo moter off yet but put volt meter on the back and it goes to about 6 volts when i change channels then drops off so imasuming its workingill check prices when i go to town tomorrow otherwise i get one on ebay like u sugested thanks again

 

[jackpeas]

Hold on not so fast/Dont go buy untill you check everything

Hi i am jackpeas@yahoo.com in Chicago,ILL.I got 1 pansat and adl 2c &2ku feed(4 lnb)4 x120'ft of cables,2 multi-switchs.I started having problems with my adl 2c 2ku with no servo motor in.I change out the 2 cband lnb and 2 cables.Still had the same problems.Getting odds on one sat and even on the next sat.Its sound like its the servo motor.I remove the 2c2ku feed/now its the coroto with servo motor having the same problems.I remove coroto #1 install coroto #2 and same problem.I have check the servo motor on 2 of my coroto/they was good.I have one more to check.Now how did I check them?you ask? I made up a 10'ft servo motor cable(the one with 3 wires,red,black,white).One end has 3 clips and the other go in the servo motor port on the back of my 4dtv.All you do is change channel and you will hear the buzzz or you can whatch the proble move.By looking in side of the feed.I had one of my feed seal and i could not see if the probe move or not. But I could hear it.I am going start out getting new 2x120"ft of rg6 cables.Now the only thing could be bad is the lnb on the feed and the 120'ft of servo motor cable that I have not check. I can not bury my cables i got trees.So i got problem tne more thing I can not tell if my ku is doing the same thing or not.Ku it seem dont 2 tp back to back,I can't think of one.I will have to do more checking on the ku side.The next part of this is feed orintation or where the ku lnb is suppose to go.For all of my sat life since the 1990/Ku lnb is suppose to at 11 or 12 o'clock with my dish pointed at my southmost sat amc3@87deg.Correct me if I am wrong.That what I be thinking when I am changing out the feed.

 

[bryansr]

I have received a FEW BAD servo motors in the time I did a lot of C Band work. In fact there is a way to adjust the new motors that didn't work. I just don't remember how I did do it do it (it involved taking the servo motor apart and adjusting it). We used to have a local satellite equipment distributor located here and I could go right to the counter and get tech. support for ALL of my equipment and a lot of tips and tricks too. I did not do a LARGE VOLUME of business but I got excellent service, because I would take on difficult service calls.

BryanSR

 

[gizzer777]

At this point

hey thanks for all the replys i havent taken that servo moter off yet but put volt meter on the back and it goes to about 6 volts when i change channels then drops off so imasuming its workingill check prices when i go to town tomorrow otherwise i get one on ebay like u sugested thanks again

Since you seem pretty certain about the servo motor being ok...I would look to make sure the motor actually is turning the probe inside the feedhorn. Just before you go replacing a lot of things...

I was unaware that the servo motors could be adjusted at all! I always assumed (that word again) that If I needed to fine tune skew, I would just use the 4dtv to do it.

here is a servo motor link (interesting about his use of the capacitor!)

http://www.tvantenna.com/support/tutorials/servo.html

I wonder if anyone else has found this necessary....mine always did just fine without that Cap!
Jeff


Regards
jeff

 

[bryansr]

I had a couple 4DTV systems that had this "fluttering" that was described in the above link. I tried the Cap several times and didn't help with these "problem children". I had to keep tweaking the system and one of them I had to do the MASTER RESET on the 4DTV to clear it up.... I just don't know!!!!!
One time I had a broken feed where the Servo motor attached and servo motor would turn but the feed "antenna" in the feed horn throat would not rotate.

BryanSR

 

[jackpeas]

Since you seem pretty certain about the servo motor being ok...I would look to make sure the motor actually is turning the probe inside the feedhorn. Just before you go replacing a lot of things...
I was unaware that the servo motors could be adjusted at all! I always assumed (that word again) that If I needed to fine tune skew, I would just use the 4dtv to do it.
here is a servo motor link (interesting about his use of the capacitor!)
http://www.tvantenna.com/support/tutorials/servo.html
I wonder if anyone else has found this necessary....mine always did just fine without that Cap!
Jeff
Regards
jeff

The feed I am going to put back on is working.I look in side at the probe it was turning 90 deg.So I adjusted it with my 4dtv.When i did a master reset.I went to opt 642 I think/where you set up your lnb to c band and ku lnb/not cband and ku lnbf.Now since you said about the probe/yes it move and buzzz.How about is it in the right place?I mean (you know H 30 and V-60) I change mine to h10 v-80.Why? When i look at it,it was pass 90 deg.I will try my qther 4dtv to see.

 

[gizzer777]

next step

The feed I am going to put back on is working.I look in side at the probe it was turning 90 deg.So I adjusted it with my 4dtv.When i did a master reset.I went to opt 642 I think/where you set up your lnb to c band and ku lnb/not cband and ku lnbf.Now since you said about the probe/yes it move and buzzz.How about is it in the right place?I mean (you know H 30 and V-60) I change mine to h10 v-80.Why? When i look at it,it was pass 90 deg.I will try my qther 4dtv to see.

Good...that eliminates the servo motor and your setting in the 4dtv lnb section sounds right (and all wires to your receiver check ok). Now try to tune to a satellite and fine tune an odd and an even station. USE THE INSTALLATION MENU FOR PROGRAM SATELLITES. and then MANUAL skew adjustment. Auto is ok to get you close but you must tweak the skew manually to really get on.


BTW: the reason it works on some satellites odd and then some satellites even, is that some sats have reverse polarity!!!