Octagon SF918 Blind Search

[starman345]

Hi,
I'm from North America and considering this Octagon box as it has automatic Pal-Ntsc detection. I am primarily a feed hunter and am wondering if anyone here can comment on how well the blind search works on this box? Also,will it blind search dvb-s2 channels or just the regular dvb-s channels? General impressions from those who own it would also be appreciated.

[peter273]

First: The theme of pal/ntsc
In dvb one makes no distinction between pal and ntsc, since those are analog signals while dvb is a purely digital stream
(thereof the term "Digital Video Broadcast").
The box however can be preset to convert the received digital stream into pal, ntsc or secam for its analog outputs.
(only the "old" sat-receivers used analog tv-signals, nowadays it's all about mpg)

Second: The theme of "blind search"
I'm not sure what you understand by the term "blind search".... or if you really say what you want to say or think it is.

Blind search:
Consider this just like slowly tuning an analog radio using the knob at the front: The user turns the knob in a smooth way, thus doing analog sweeping until music is heard (a signal is captured).
In the same way the digital radios "sweep" the full band by very little steps, meanwhile "listening" to find a carrier, then locking into it.
This is "blind search", the user or digital system does not know if a channel comes up thus searches the full band slowly to find channels.

NIT search (=Network Information Table):
Consider this like a digital-interfaced radio which was preset with a number of stations.
When "scanning" those presets, it goes from one preset to another.
NIT search has the capability of capturing embedded digital info of a specific preset, info telling it that this specific preset has "sister presets" which can also be tuned into.
The digital radio will then add those to its presets automatically.
Translated: The presets are here in fact transponders, all of them carrying several channels and NIT.

Then for the answer:
The box does not do a real blind search (analog or quasi-analog scanning), what it does is a NIT search of every pre-programmed transponder, thus adding additional transponders if any information of them is found in the NIT table of a transponder.
If for any reason a new transponder is NOT in the NIT information of any of the pre-programmed transponders it will not be found, so it's upto the user to add those new transponders to the transponderlist manually.
The newly added transponder however CAN have additional NIT table information, thus furthermore expanding the number of transponders cq channels automatically.
I guess most boxes don't really do a real "blind search", and most users mix "blind search" and "NIT search" up, not really knowing what it actually means....

One tip however: if searching make sure to set NIT to ON (it defaults to OFF).

And yes, if NIT information carries info on DVB-S2 transponders they will be added just as well as DVB-S transponders.
The system works flawlessly in my opinion, no complaints so far....

However when purchasing a new box, best is to manually check ALL preprogrammed transponders "programmed by the factory", since some have small errors in it (qpsk instead of 8psk, pilot on or off, dvb-s instead of dvb-s2).
Small errors since nobody is perfect (not even the programmers), it just takes a couple of hours to find and fix those if you really want a "clean" system.
Most users will not even notice those errors, since if having NIT set to on while searching the correct ones will be automatically added to the TP list.

I hope this answers your question in full.

Greetz

[starman345]

Thanks for your indepth answer. No blind search, that's what I suspected. I've had many receivers over the last 7-8 years, most which have had real blind search but they are non HD, most of the North American HD boxes have no blind scan or only blind scan of dvb-s signals, not dvb-s2.
More and more of our signals are being switched to dvb-s2 so a blind scan receiver capable of logging dvb-s2 signals is becoming more of a neccesity. As I said in my initial post, I am a feed hunter, not looking for stuff on the established transponder lists, we have a lot of wild feeds on both c band and ku band, thus my search for a receiver that can find them.
Thanks again.:respect-049:

[boxspanner 2002]

Hi peter273
thanks for info on blind search and nit
question how do i find new transponders
and if i do, how do i add them to my reciever
do the frequent firmware patches, include them ?
regards boxspanner2002 /newbie

[peter273]

@starman

Real blind search for dvb-s AND dvb-s2 would make searching terribly slow looking at all possible parameters to be varied....
Most "common users" will not accept that, therefor most box-builders won't support it I think.


@boxspanner

You can use sites like for instance:
to trace and find unknown transponders.
There will be many more of those sites around, I'm sure of that.

I have spent an evening correlating what's in the box and add them manually (if necessary) using the info for the sats I'm interested in.

Adding a transponder in the box is easy enough: Go to the search menu, on the bottom you'll see "colored buttons" corresponding to those on the remote to add or edit transponders.
Just fill in the data of the sites I mentioned then => done

And as I said before: The default list in the box is not always fully correct, so the freak I am I immediately corrected them :rofl:.

Greetz

[starman345]

@starman

Real blind search for dvb-s AND dvb-s2 would make searching terribly slow looking at all possible parameters to be varied....
Most "common users" will not accept that, therefor most box-builders won't support it I think.

There are boxes already doing this..Clarke Tech 5000 HD Plus Combo, and the very similar if not the same Technomate 6900 super HD Combo,(gotta love those catchy names), nothing slow about them according to reports on the various forums. Keep in mind these new chips do hardware blind scan, not software.
On this side of the world, Lyngsat is outdated, I believe it is administered in Scandinavia? They can't see the satellites I see here, so they rely on reports from the west to keep current. Can you see how blind scan is important? Remember I am a feed hunter....
I agree common users couldn't care less, strangely the box builders are supporting it.:applause-003:

[eazy]

Maybe new Octagon models will support this feature. Let's wait and see.