Bad LNB or bad cables/connectors?

[Eric Auer]

Hi. I'm new to this forum, so I'll give you a brief background on my situation:

I have been a DirecTV subscriber since 1997. During that time I have upgraded my receiver, added an UltimateTV receiver, replaced my cables once, and moved my dish once. My dish and cables have been working great and haven't been moved for over 3 years now. Currently both cables from my dual LNB feed into a 4-way multiplexer (non-powered) inside the house. Lines 1 and 2 from the multiplexer feed my UltimateTV receiver, line 3 feeds my other satellite receiver, and line 4 is not used.

Now for my question:

I haven't used the dish much at all over the last 2 months or so. This week I turned it on and found many channels not working. I turned on the UltimateTV, and it wouldn't come in at all, claiming that it could not locate the program guide. Using the Signal Meter on both receivers, I found that none of the even transponders are coming in at all on any of the 3 lines. The odd transponders are coming in very well.

I find it hard to believe that my cables or connectors are at fault, since there are 2 lines from the LNB to the house, and both are displaying the same exact problem. For the same reason, I doubt that there is a problem with either of my satellite receivers. I plan to check for rusty connectors and replace them if necessary, but I suspect that my LNB needs to be replaced.

Does anyone here have experience with this kind of symptom-- the receiver failing to receive all even (or all odd) transponders? If so, was the problem with the LNB? Also, if anyone recommends any particular diagnostics, I would love to hear them.

Thanks in advance for your help.

Eric

[Eric Auer]

Oops. Sorry for the typo-- my cables feed into a 4-way multiswitch inside the house.

-Eric

[Karl Foster]

It sounds to me like your multi-switch is bad. I would bypass the multi-switch and run the two lines directly into your UTV, if you can. That way you can isolate whether it is the switch or not.

[Martyva]

Check for moisture at any of your outside contacts between the LNB and your house.

[boba]

I agree the multiswitch has the greatest chance of being your problem, the cable carrying the even transponders from the LNBF to the multiswitch could also be you problem. I like Karl f's idea of connecting both lines to the ultimate receiver if one line works and the other dosen't you have narrowed it down to the LNBF or the cable, if both work the multiswitch.

[Eric Auer]

Thanks Karl, Martyva, and boba. This all seems like sound advice to me. I think I'll stop at Radio Shack today and look for couplers that will allow me to connect 2 F-connectors to one another. That way, I can bypass my multiswitch easily without having to run any additional cables or mess with the connections in the back of the Ultimate TV receiver.

boba, you said that my problem could be "the cable carrying the even transponders from the LNBF to the multiswitch". It's been years since I've read about the technical details of dbs and multiswitches in particular, so let me see if I have this straight:

The LNBF uses one voltage to receive signals from all of the odd transponders, and another voltage for the even transponders. These voltages travel to the dish from the satellite receiver(s). Applying the same voltage redundantly can fry the LNBF, which is why regular coax splitters cannot be used to send the satellite signal to multiple receivers. The multiswitch prevents that problem by using one line for even transponders and another for odd transponders, and supplying each of its outputs with the appropriate signal. The multiswitch will never receive signals from the same set of transponders on both inputs simultaneously.

If I understand this correctly, then I was wrong in one of the points I made in my first message. I claimed that since all 3 of my tuners (2 in the Ultimate TV and one in my other receiver) displayed the same problem, that cables/connections were unlikely to be my problem. I figured that both of my exterior cables would have to be compromised in order for that to happen. Now, after reading your replys and giving this some more thought, I believe that having one exterior cable or connector damaged or wet could cause exactly this problem. Does this make sense, or am I misunderstanding something?

Anyway, I will first bypass the multiswitch and see what happens there. If one line works and the other doesn't, then I will check all of the connectors on the bad line.

Thanks again for all of your help!

Eric