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I don't think here that there are different flavors of the NETWORK SEARCH in this case. I think that they used a slightly incorrect terminology here. It should probably be stated as NIT SEARCH.... ON/OFF.
The way I understand NIT search is that there is a table (the Network Information Table or NIT) available on one of the providers TPs and if you scan that one particular TP, the receiver loads that table into memory. The table contains the entire list of all the other sats and TPs and channels available from that one provider.
I have never seen this NIT search actually function with any receiver I have ever owned.
I *THINK* I've seen it function a couple times. I can't remember which sats, but I think once on the then G25 (G19) sat with those Globecast things (I may be wrong about that), and once on either a DN or Nimiq sat when I was trying to scan in a channel that happened to be FTA. In both cases, I was trying to just scan in one channel on one transponder, but accidently hit network search, ane it started scanning all the transponders in the network. I can't remember if it created new transponders or if I already had the transponders entered into the receiver.
The thing that amazes me about the function is that while the NIT has some standardization, always on PID#16, and there seem to be a few standard entries, it seems like different services have significant differences with respect to what they put into the NIT, and there doesn't seem to be enough standardization to allow a consumer receiver to know what to do with the info. DN, for example, has a list of EVERY DN sat, and every transponder on each of those sats. I wasn't sure how it figured out which sat the receiver is currently tuning, but I just looked at a DN NIT, and it seems to have a "Current Network: TRUE" parameter on all the transponders on the current sat, and not on any transponders listed for other sats. So I guess receivers must look for entries that have this parameter set as true, and then go to scan those transponders. I'm not sure what receivers would do if the transponder isn't already in the list, and/or if the listed freq is different, etc, plus the NIT generally doesn't completely specify the modulation mode, often giving a list of possible modes. I'm also not sure what it would do when it sees a dozen different spot beams with the same freq.
It's not important to me, since I never intentionally use the network search, but I'm just curious about how it works. I may go to one of those DN sats where I've deleted some or all of the transponders, and see what it actually does, ie whether it creates new transponders when they're missing, and what it does if the freq or SR is different from what's in the receiver.
Another interesting oddity. Many receivers pop up the name of the sat you're on, if it happens to be listed in the NIT of the transponder you're tuned to. The interesting thing about the DN sat I just tuned to is that some of the NIT transponder entries list the sat name, others don't. It seems to pick up the sat name, even if the sat name isn't listed under the NIT entry for the transponder you're tuned to, so it must search through all the entries looking for the sat name. The DN NIT has 576 entries, and there are sat name entries on about a only a fraction of the entries, but it's listed for all of the sats. So it must search for sat names in an entry that has the Current Network=true parameter set.
Anyway, it's interesting how it works, particularly because MOST sat transponders don't even have an NIT PID, and most that do, don't have correct info in them. So I'm guessing that network search would only work on a very few networks that keep useful info in the NIT.