Which is dead? LNBF or Receiver?

[davy_gravy]

I have a GlobeCast TV SE830-x that is about 2-3 years old. The unit came w/ a dish and LNBF.

We bought it so my wife could watch BNV-TV fta broadcasts ... It worked fine through GlobeCast, and then also afterwards when Globecast dropped BVN-TV, it also worked fine (I had to go up on the roof and reposition it - for the last year we have had a good signal strength and good signal quality via AMC4 at 101W).

Out of the blue it stopped working. Symptoms:
Signal Strength 0
Signal Quality 0

Known good cables - triple checked.
No lightning strikes/storms that correspond to problem. Also, no visible or known damage to either receiver or dish/lnbf.
Tried resetting to factory defaults and reprogramming settings.
Went up on roof w/ known good cables and TV to double check things.

Questions:
1. Is there a way I can determine whether it is the LNBF or the Reciever? ...something easy?


2. Does transponder # matter? The GlobeCast receiver I have doesn't me to enter a transponder # of 21. Only 1 & 2 are available. The original insstructions I followed specifed TP1, not TP21. Previously TP1 worked fine, but now in the LyngeSat site I see it listed w/ TP21. Is this transponder buisiness a "red herring"?


3. If I need to replace either the LNBF or the Receiver, and I still want to get FTA programming, via AMC4, are there a few cost effective solutions you can point me to that are known to work w/ AMC4? Ideally I'd like to keep the dish that I have already, and replace only what is faulty.

thanks for your time

davy

 

[Mr Tony]

signal strength 0 means the receiver is not getting power to the LNB. Now is it the box or LNB?

I take it there is no other receiver or LNB you have laying around to try? Dang even if you had ANY other LNB around you could hook it up to see if there is power to the LNB. Even if you're not aimed at anything the signal strength meter on the receiver should register something

On the Globecast box, can you enter another transponder into it? Something like 11822 H 5700 (freq, pol, symbol rate).

I thought maybe the dish moved but you would still have a signal strength reading on the LNB.

 

[davy_gravy]

I take it there is no other receiver or LNB you have laying around to try? Dang even if you had ANY other LNB around you could hook it up to see if there is power to the LNB. Even if you're not aimed at anything the signal strength meter on the receiver should register something.

... hmmm... I'll call the retired gentleman up the street who used to install dishes...

On the Globecast box, can you enter another transponder into it? Something like 11822 H 5700 (freq, pol, symbol rate).

those three options are available... I entered the values they list...

I thought maybe the dish moved but you would still have a signal strength reading on the LNB.

... my thought as well...


After looking at some things, I see now that a new LNBF from Sadoun costs about $35... that's not chicken feed, but it might be the first thing I'd try if I can't get a spare LNBF to try...

 

[Smith P.]

Wouln't be easy to check voltage on SAT_IN connector ?

 

[davy_gravy]

alas, I have no multimeter...

 

[Smith P.]

Ask your neighbor or friends or co-worker or relatives ...

 

[Mr Tony]

Stupid thought

UNplug the box from the outlet and then plug it back in. Sometimes it may kickstart the system

 

[satcom1]

I bought SF-95c+ on ebay for 99 cents got it in three days first class mail. Be handy for you to check this problem and next time dish blows over.

 

[Smith P.]

Oh boy ! Take a 12V lamp from your truck and use it switching polarity H to V and back.

 

[satcom1]

Oh boy ! Take a 12V lamp from your truck and use it switching polarity H to V and back.

Not a great idea some automotive bulbs draw more then one amp and you could fry a perfectly good receiver. Flashlight lamp could be safe if not a Krypton maglight bulb.

 

[Smith P.]

You right - check if the bulb req no more then 750 mA !

 

[davy_gravy]

Wouln't be easy to check voltage on SAT_IN connector ?

What kind of reading should I get on it? Is there an expected range?

 

[Mr Tony]

13-18v

if you are on a horizontal polarity channel it should read 18-20v and vertical would be 13-15volts

 

[davy_gravy]

OK, if I understand this correctly...

1. I attach a known good cable to the SAT_IN port on the back of the receiver...

2. I turn the multimeter to 50V DC say, probe the other end of the cable at the connector (outer part that would screw onto the LNBF) and the central copper wire that comes out of the connector. I should get those readings you mention.

Does this sound right?

 

[Smith P.]

Yes.

 

[davy_gravy]

OK, did it and it reads zero. To me that seems it (receiver) must be shot.

Is there any expected reading for the LNBF? Maybe a certain resistance?

In terms of chicken and egg, I'm wondering if both are bad... Could a faulty LNBF burn out a receiver?

 

[Mr Tony]

sounds like the receiver. If a receiver goes bad usually the LNB is still good

 

[Smith P.]

Should be from 2 KOhm to 20 KOhm for the LNBF.
As to receiver, there is big chip with name LNBPxxx or big transistor with a heatsink, close to sat-tuner, trace direct wide path from F-connector to that component. Also could be bad Zener diode connected to same line.

 

[davy_gravy]

Thanks, that was helpful... It reads about 2.4k ohms on the LNBF...

I have just ordered a receiver ... so I am in a wait-and-see mode for now. I will post back once everything is resolved. Much appreciated for all help and advice...

 

[Smith P.]

Can you open the box and make a macro photo of sat-tuner and close to it part of PCB ?