At least I think this is
Mercury behavior, as it's possible that the Motor and/or
DiseqC switch may also be involved.
Anyway, I have a 90CM/Sg2100/QPH031 and a fixed Primestar dish/Kul1, side by side, both feeding a 4x1 DiseqC switch going to my Mercury.
Both dishes were aimed at AMC3 a week ago, and were giving me good signals on the
PBS channels. Then, we got about a foot of snow, which shouldn't have hurt anything, as nothing stuck to the dishes, but over a few days, I noticed that I had lost signal on both dishes. I assumed that my fixed dish had shifted, since it is mounted on a portable mount on a log that I can move around to get a view of different sats, so it made sense that the snow may have moved the log. However it didn't make sense that the 90CM dish would have moved, since it's on a pole sunk in concrete.
So I decided to see if I could tweak the reception a bit. I've been using DiseqC-1.2 to move the motor, so I started bumping the motor east and west, hoping to get reception. I was having problems finding the signal, so I moved the dish to a couple sats west of AMC3, and they came in fine, but back to AMC3, and nothing.
THEN, I remembered. At some point in time, I had inserted a satellite east of AMC3, and I remembered the bug in the Mercury firmware, that was first discovered by Bill190, ie see:
http://www.sadoun.net/forums/fortec-...ury+diseqc-1.2
ie the Mercury seems to have a problem whereby the DiseqC1.2 position numbers get scrambled, and it will send the dish to the wrong satellite.
So I decided that I must have scrambled the AMC3 position somehow. So I decided to switch back to USALS, which I had not been using since my motor's zero is slightly off. But USALS usually gets me close enough to see the signal. So I switched to USALS. Got signal back on AMC3, but it was poor, since the zero is off. So I decided to alter my longitude to get it synced right. My actual longitude is about 70.78, so I decided to experiment by increasing/decreasing this value by small amounts. However THEN, I ran into yet ANOTHER bug of the Mercury, which again was first noticed by Bill190, ie that in some menus, the signal/quality meters don't work. Ie if I'm in that USALS menu, and have a signal/quality reading, and make ANY change to ANYTHING, but in this case, make a small change to the longitude, then I completely lose the signal/quality meter readings. This makes it very hard to make fine adjustments. In the past, I've had to make an adjustment, and instead of being able to use the meter in the menu I've been in, I've had to back completely out of the menus, and see how the change has altered my reception, then go back into the menus, etc, etc. THis is very time consuming, so I decided to speed things up by using another receiver. I fed the Mercury's passthru to my
Twinhan, and used the Thmover.exe program to monitor the signal/quality, figuring that even if the meters on the Mercury weren't working, that I could use the Twinhan to measure the signal. WRONG! It turns out that it isn't that the METERS don't work on the Mercury, it's that the Mercury completely kills the signal somehow, when in those menus. HOWEVER, I DID find out, that I could usually (not always) get the signal to come back, by switching transponders, {usually it had to be a transponder of the opposite polarity} for example, if I changed my longitude to 71.0, I'd lose all signal/quality when I left the longitude selection (which is when the Mercury would say 'moving to sat position'). However if I'd go up to the transponder, change to another transponder, then back to the transponder I was previously on, I'd usually get the meters functioning again, and the meters on my Twinhan via Thmover also went to zero then came back, showing that it wasn't just that the meters weren't working, but that I wasn't getting any signal.
Anyway, I worked on the darn thing for nearly a half hour, and ended up getting a strong signal when I'd set my longitude at 71.7. I turned off Thmover, and started up TSREADER on my computer, and was getting good reception on the PBS signal I was tuning on. So I thought GOOD, this seems to work. So I left that 71.7 longitude in there, and backed out of the USALS menu, and instantly, the signal/quality went away on the Mercury, and I lost reception on the Twinhan!?!?!?!? I went back into the USALS menu, and it was still set on 71.7, so I started over again, adjusting longitude. I couldn't find signal anywhere. Put the longitude back at my actual 70.8. Sent the motor to zero, and back to AMC3.... finally got back to the poor reception I started with an hour ago. Started to go through the same process of adjusting the longitude, but this time it ended up showing the best reception when I had the longitude set at about 70.1, ie in the other direction?!?!? Since my original intent in all of this, was simply to get some reception on AMC3 so I could watch a program on PBS, I finally just quit... this time when I exited the menus, I WAS able to get back and was able to view programming out of the menus. So I never did figure out what was going on.
Another weird thing that was going on during all of this, was that initially, when looking for signal, I was using the 12180V/30000 transponder, but wasn't finding anything, so I switched to the 12163H/4444 transponder, and I finally found the signal using that transponder. However after peaking on that transponder, I switched back to 12180V, and it wasn't there, however after peaking on that for a while, I got a good signal on that, and tried switching back to 12163H, and IT wasn't there?!?!? I eventually got the thing working, and am able to switch back and forth between the various transponders, but this darn thing was doing WEIRD THINGS.
Looking back at what I observed, I'm almost convinced that the problem may not be completely with the Mercury, but may be partially related to the
SG2100 motor, and/or the DiseqC switch. Ie I'm thinking that somehow I may be losing lnbf voltage to the LNBF whenever the motor starts to move, and/or whenever I switch polarity. Perhaps my long (~250') coax run is making the lnbf voltage marginal whenever the motor is trying to move. I've previously noticed that some DiseqC switches also seem to decrease lnbf voltage even with short (10') coax runs, so it's possible that the DiseqC switch might also be involved. I've also noticed, that at least with my old Ultra and Lifetime, that whenever the receiver loses lock, that it will try to send out DiseqC signals, apparently trying to make sure that the switch is in the proper position. I'm half wondering if the receiver also sends out DiseqC-1.2 commands to the motor when it loses lock, but I doubt that it does this.
But bottom line is that something is seriously wrong with the Mercury firmware, and it just got worse for me over the past week, for no apparent reason. I am really confused at what is going on with the dumb receiver. I'm tempted to switch back to my old Lifetime receiver, which has a functional DiseqC-1.2 capability, reprogram the motor, then use a binary editor to re-program the Mercury's memory to match those settings. Seems like a lot of work, but anything is easier than fighting with this dumb Mercury losing signal every time I make a change.
Bad thing is that I may have to wait till spring to play with the thing, since I'm up to my lnbs in snow and ice here. I may just re-aim my fixed Primestar dish, and forget about the 90CM until spring.