I admit up front I have posted regarding this before, but thanks to the gurus here and some testing, I now have further info. I also posted that in the wrong place.
Briefly, I have a non-SWM SL5 and 4 HR2x's.
The oldest HR20 intermittently loses tuner 1 completely, but only on 103s. A reboot brings it back for a day, a week, whatever. The other tuner does not lose connection, and no other sat loses connection. I have watched shows recorded on this DVR and some of them show brief severe pixellation. Others do not. Signal levels are good; I have 100 on the main spot beam xponder. Except when I have zero on tuner 1. I get a lot of blank recordings, and probably because of this issue. Most of what I record comes from the spot beams on 103s (go figure).
I have replaced both BB converters, and if I swap feeds at the back of the DVR, Tuner 1 is still the one missing. The other 3 DVRs never have this issue.
Originally I thought since it affected only one sat it was the switch in the LNBF. I planned to replace it with SWM, but now I fear that the problem is really in the DVR, and that going to SWM might even aggravate the problem, so I am holding off on that changeover.
A "tuner" is really a number of things, including a heterodyne converter front end to get the signal from L-band to IF, another converter to demodulate it to baseband, a router (the fact that I can swap input cables and tuner 1 is still the one with the issue implies that there is a router that enables either RF input to be routed to either tuner), and demux. The particular symptoms seem to point to the problem being either at the router point or downstream of that. And of course there are two independent tuner paths up to that point (four if you count OTA), and two independent routers/demuxes, for a grand total of two complete tuner paths.
Here is another clue; the OTA signal also disappears on tuner 1 on occasion, and it appears that if I lose tuner 1 on sat, I also lose it on OTA. Since that is a separate demod path but is probably routed into the same path just before demux that the sat signals are routed into, that implies that the problem is downstream of demodulation, in the tuner 1 path.
But I need the experts' take on this.
I also need to hear what you think about whether moving to SWM would improve the issue, make it worse, or probably not affect it one way or another (I sort of think the last choice is most likely).
Also, where is the info that marries the database to the HDD? My guess is that it would be on the board with the tuners, but it it is instead on the board that has the power supply and microprossessor, I can get my hands on a spare actually brand-new tuner board, and I could then theoretically swap out the tuner board, keep the PS/microprocessor board, fix this problem, and still be able to play back existing recordings. Probably wishful thinking. Does anyone know?
BTW, this is a Pace DVR. Please, no warnings about popping the hood; that boat sailed a long time ago.
Edited by TomCat, 19 November 2013 - 12:38 AM.