Should an LNB be hot to touch in the shade?

[wavebender]

All,


I am a NOOB with a recently acquired PANSAT 150, SG2100, and Fortec 80cm dish with stock fortec standard LNB.

The dish and LNB are a $45 find on craigslist. The rest of the gear is brand spanking new including triple shielded RG6 cables with premade ends.

I have some concerns abou the LNB. As I cannot seem to tune in a signal. I am trying to tune in galaxy 19 (my southern most sat); I get about 85% signal strength with ZERO quality.

I fooled around with different settings and satellites which did not change status. After several hours of no luck I packed up my gear for another day. When I unscrewed the RG6 from the LNB I noticed the the F connector and the entire LNB was noticably hot.... even after minutes of having the receiver off.
.
The cover the the LNB input has sun rotted away. Peering in I see no obvious shorting or debris. Just a pin-like wire situated in the center of the LNB.

This is my first experience with sat gear and while I don't think it unreasonable for a powered device such as LNB to generate heat it seemed very hot... just short of burning... So I am concerned but lack the experience to fully evaluate what I'm dealing with.

Any trouble shooting advice is much appreciated to verify the integrity of the LNB.

Best Regards,

Wave

 

[Long Hair]

I assume your trying to get ku-band,in your options menu what do you
have the lnb set to. LNB Type: UNIVERSAL - Low: 9750, High: 10600).If you are using a "Standard" LNBF, then low:0 and High: 10750. hope this helps

 

[nycrich]

The system is drawing too much current. As a result it will get very hot (if your settings are wrong "Universal vs Linear it will not cause the overheat problem). It could be the coaxial, receiver , or lnb. However from your visual inspection it looks like the lnb might be bad. It could be a corrosion issue that is causing the short in the lnb, naming a surfce mount component that have corroded or cold solder joint.
You can rule out the coxial cable by trying another cable even if it is short and you have to be close to the dish. However you will need another lnb to rule out your problem . These are usually not expensive on Ebay. If your receiver was shorting out, it would be switching off, therefore the lnb looks like the suspected cause of the problem.

 

[wavebender]

LongHair, NYCRich,

Many thanks for your reply's. I'll check settings and purchase a new LNB. I'll dissect the old one later tomorrow to see how its put together.

-wave

 

[Gary Z]

What part of Texas are you from? I am near San Antonio

 

[nycrich]

I've had similiar overheating problem before. My lnb dropped and I tried using it outside with a cracked casing (plastic cover). When it rained water entered and then dried inside, causing corrosion. I noticed firstly a remarkably drop in signal quality and when I tried to investigate, the lnb was burning hot. I did open it and found corrosion across the circuit board of the lnb.
Hopefully you will have better luck with the new lnb. Sometimes you can clean the corrosion depending on the severity and use the lnb as a spare/backup.