That's one of my pet peeves. It's very frustrating to get someone in tech support who a) has no knowledge at all other than what's on the checklist in front of them and b) certainly doesn't know as much as you do, particularly when it comes to first principles or logic and c) doesn't know that they don't know, and answer your questions with gibberish, often in a condescending way as though you're the idiot.

This happens all too frequently, and it happened again today with DirecTV.

I've got a weird problem. Intermittently, I'll lose signal on some channels, starting with pixelation and audio breakup, deteriorating into complete loss of satellite signal. The last time I was having a problem like that, in California, it turned out to be a bad LNB, so I went out and bought a new one, and installed it.

The problem persists. Now here's the really strange part.

When I run a test on the individual transponders while it's acting up, the odd-numbered ones are fine, with signal strengths in the nineties. The even-numbered ones are zero across the board. What kind of failure would cause this kind of selective behavior? What's different between odd-numbered and even-numbered transponders that would cause one to be fine and the other useless? I thought it might be something in the logic programming of the receiver, but I hooked another one up, and saw exactly the same behavior.

It seemed like an intriguing problem to me, and I figured that if I talked to DirecTV about it, they'd have some kind of ready explanation. And indeed they might, if you could actually talk to someone who understands how the system works, instead of a drone with a checklist, who not only couldn't explain it, but didn't seem to think it remarkable. He simply kept leading me through his check list. When I explained to him that even was bad and odd was good, he could only repeat, "that means it's seeking signal," as though that actually meant something significant and useful.

The bottom line was that he said he'd send someone out to look at it. On October 12th. I'm tempted to make another attempt to see if this time I can at least get someone with a little intellectual curiousity, and ability to think, but I'm wondering if anyone out there has any insight.

It's not the receiver, it's not the LNB. It could be dish aim, but the problem with this, as with all hypotheses, is that it doesn't explain why I have a perfect signal on odd transponders and zero on the evens. Same thing with a bad cable, which is the only other thing that I can try at my end.

If someone described the symptoms to me, and I had no other knowledge, my first guess was a problem with the transponders on the satellite itself. But that implies that everyone else would be having the same problem, and it's hard to imagine that occurring for long without DirecTV doing something about it.

Anyway, I guess I'll try swapping cables, just because there's nothing else I haven't tried, but if that's the problem, I'll be very interested to understand what kind of cable failure would affect half the transponders, and only those with even numbers.

[Update on Sunday morning]

Thanks for the input. I finally did get in touch with someone at DirecTV who knew what they were talking about, and he told me that the most common reason for this behavior was cabling, with receiver second, and LNB a distant third. He couldn't explain the physics of it, but said that in his experience, it was usually a bent pin on a cable, or some similar problem.

I went out this morning, and started tracing the wire. I found a corroded connector where it goes into the house on the active line. When I moved it to the other side (on a line we aren't currently using), which wasn't corroded, the problem seems to have gone away. I'll have to watch for a while to see if it recurs, but that looks like it was the culprit. I'll have to go to Home Depot and get a replacement for it, and seal it back up out of the weather (it only had electrical tape wrapped around it, which is probably why it went south).

We had this problem with Dish, which never was resolved--during poor signal reception times the even (or was it the odd?) numbered transponders dropped out. I had this recollection that odd numbered transponders are transmitted using one polarization and even numbered tranponders are transmitted with a different polarization, and online sources seem to confirm this, so perhaps this has something to do with these problems.

Rand, I had a very similar problem with my DVR Dish Network dish, with the exception that the tech support guy actually knew what he was talking about. In my case it was a software problem and fixing it consisted of unplugging the receiver for a while, and resetting it to let the OS reboot. It took two tries for it to work. Sounds stupid, but it worked.

As for the brain-dead tech support -- what would you charge on an hourly basis to sit in a call center and answer questions, most of which could be solved with that proverbial checklist, waiting for the one interesting call that comes along every week and a half? Me, I'd need at least $100/hour to consider doing it.

I suspect most people with the appropriate skills think similarly. Ipso facto, the fact that you get ill-informed tech support tells you the market price for the service is not high enough to pay for well-informed tech support.

Rand, we had this problem with our DirecTV dish, turned out it was indeed the target. Something went wonky inside the target, the tech came out and replaced it and everything's fine.

Aleta, I don't know what you mean by "the target." If you mean the LNB (the horn that the dish focuses on), I replaced it last Saturday.

There are people there who know what they're doing, but they're surrounded by a protective field of "drones with checklists", as you said (I had lots of problem with Comcast cable, and I finally managed to get to some sharp techs).

The key is to figure out how, in their organization, to elevate your call to reach the REAL techs. More likely, they will escalate your call to a "supervisor", i.e. another drone with a checklist who has a few minutes training in difficult-customer-management.

Threaten to reverse the polarity of the neutron flow and destroy their satellite unless you can speak to an expert. They do not like it when their satellites are destroyed.

There's a good Dilbert cartoon about this kind of thing. As I recall, Dilbert is on the phone with a technician saying something like, "Look, the problem isn't at my end. I have three computers in the house, and my e-mail on ALL THREE went out simultaneously, while the Internet service is working fine." [or something like that, probably more specific to justify what he said in the second panel, which was:] "Therefore the problem is at YOUR end. Can your mind grasp that?" Then in the third panel, Dilbert is reclining on the sofa with a cup of coffee, talking into his phone. "Okay, I'm rebooting my computer. Hey, guess what? That didn't work either."

Could the Hurricane have goten water into your coax?

Compressed/encrypted digital signals probably work differently, but on the old C-band dishes (my family installed more of them than I can count), the even and odd channels were on different polarities (horizontal and vertical). I know that this sounds like Trek technobabble (you *always* win by reversing the polarity!), but there was a mechanical device on the feedhorn assembly, right next to the LNB, that was called the polorotor, which flipped between the two polarities as you went from even/odd channels.

I haven't had a small dish for a couple of years, now, but I don't remember seeing anything that looked (or sounded--it was rather distinctive) like a polorotor, but there could be an electronic or software equivalent of it still in use today. Something like that being off would easily explain the situation... when a polorotor motor died on a C-band dish, you lost half your channels (even or odd) depending on which polarity it was on when it died.

I would agree with the suggestion that maybe our recent bout of hurricanes has gotten water into the cable someplace. If there are any outdoor couplers in your line, try replacing those first as they're prone to trapping water and causing odd problems. Otherwise, try a complete new run of cable - it worked great on my parents' DTV system when they had weak signals for no reason.

Yes, the problem is related to polarization. Modern dishes don't have polorotors. What they have instead is two antennas at right angles (simplifying) which are switched electronically.

I have no idea which channels are horizontal and which vertical -- they could, in fact, be left-hand and right-hand helical polarization. I would try, first, re-booting the receiver as outlined above, in case a software bug isn't selecting the proper polarization or the decoder isn't applying the selection.

Next I would look at the dish itself and the aiming. Polarization is in a way mechanical -- putting a wire across the dish vertically would cause horizontally polarized signals to come it at lower strength; a mesh of vertical wires would completely eliminate horizontal while allowing vertical to pass. It could be as stupid as rain stains or bird droppings making vertical streaks down the dish! Or, if there are overhead wires in the way of the signal they would suppress the vertical in favor of the horizontal. It can even do so if the wires aren't directly in the way, by causing multipath -- but that would suppress the horizontal by spoofing the processor's multipath rejection routines.

The dish itself could be distorted. If it were compressed a bit across one axis the two different polarizations would come to a focus at different places. Try loosening the bolts that hold the LNA arm and moving it up and down; check and see if the curve is different in the two directions. That's hard, because the dish isn't an on-axis parabola and it naturally has different curvature left-right vs. up-down. It's also made by stamping, and residual stresses may have relieved themselves causing wrong curvature.

Replacing the wire is worth trying if it's easy to do, but I have zero confidence that it would do any good. Maybe you could run a parallel one temporarily to see what happens. But I would clean the dish thoroughly and check the aiming first.

Regards,
Ric Locke

Yes, the singnals on the different transponders are polarized vertically and horizontally (not circularly).

As for tech support guys with checklists, have you considered how many people call up, claiming to be technically literate but in fact are completely clueless? I'd bet money that of the set of people who claim to know what they're doing to the tech support person, less than 10% actually do.

Mr. Simberg -
FWIW, we have the same problem here if we get a heavy rain - the pic and sound begin to break up, and then the whole thing goes until the weather clears. DTV - normally quite helpful with us - has never been able to come up with anything other than a generic reception problem which they can't trace. (TimeWarner cable does the same thing, oddly enough.)

Mike

Ric's suggestion was the first thing that came to my mind when I was reading the pre-update, though I couldn't be sure that small-dish systems would work the same as the C-band system we had in Alaska.

Anyway, here's hoping you've got the problem solved now.

Switch to Dish Network. The few times I have had problems, the customer support has been quite helpful.

From the tech support front lines:

Techs arrive as green, basically useless proto-nerds. They get varying amounts of training, depending on the product and the organization, work for a while at steadily increasing levels of competence (juvenile nerd) and then get frustrated and leave (adult nerd), either to a support position more insulated from the constant load of customers with elementary problems, or to another job entirely.

This is why it is difficult to find competent tech support. The burn-out rate is horrific, because even if your job doesn't get sent to India, you will outgrow it faster than it can grow.