Need a refresher on blind scan vs regular...

[giraffejumper]

Which is better to use, a blind scan or regular?
I am beginning to think that blind scans are only good for figuring out what exactly you are pointed at.
If I do a normal scan on the transponders that are loaded in my Viewsat - they are weak.
And I get a lesser amount than if I blind scan. But the blind scans seem to find the channels "a little off" their given frequency, therefore making them really strong or really weak.
However, it seems that if I add a transponder with an exact frequency from Lyngsat or elsewhere - it is a lot better.
It is kind of like the difference between putting radio station 97.3 on 97.1 when the station is actually 97.3. It will still pick up, but not as good as if it is right on.
Should I just erase all the preloaded tp's and input the Lyngsat one's?
But here is what throws me off. Different sights also list the channels as slightly different frequencies.
How do you know what the EXACT frequency is like on a radio station, or does that matter?
Thanks,
-phil

 

[qwert1515]

The scans do two completely different things.

A Satellite scan only scans transponders that your receiver has in its memory.

A Blind scan will find all active transponders on a satellite, a must for finding feeds.

The frequencies that you find can be off a bit due to LNB drift which can be caused by different temperatures or your equipment may detect certain things differently compared to others receivers.

Also most digital radio equipment including a FTA receiver uses a system called "PLL" which locks onto the correct center frequency when you give a frequency close to the correct one.

A phase-locked loop or phase lock loop (PLL) is an electronic control system that generates a signal that has a fixed relation to the phase of a "reference" signal. A phase-locked loop circuit responds to both the frequency and the phase of the input signals, automatically raising or lowering the frequency of a controlled oscillator until it is matched to the reference in both frequency and phase. A phase-locked loop is an example of a control system using negative feedback. Phase-locked loops are widely used in radio, telecommunications, computers and other electronic applications. They may generate stable frequencies, recover a signal from a noisy communication channel, or distribute clock timing pulses in digital logic designs such as microprocessors. Since a single integrated circuit can provide a complete phase-locked-loop building block, the technique is widely used in modern electronic devices, with output frequencies from a fraction of a cycle per second up to many gigahertz.

Link to WIKI's Full Article on PLL

 

[BarneyBean]

Also some of the info on Lyngsat is a couple of days old so that dosent help much when your trying to find Feeds since they come and go. I blind scan everything.

 

[giraffejumper]

Ok, so when you are watching a channel and it gives out specific transponder info, is that the main one you should be aiming for?

I'll have a channel say it's frequency is a little off from the blind scanned one I have found.
When I manually scan the frequency they give, it comes in at a better signal and quality. And sometimes it even shows the actual channel name instead of just "globec 012" or some other numbered generic name.
This is what prompted me to ask the question.
Thanks for the answers.
-phil

 

[Mr Tony]

most LNB's have drift which can make the frequency off by 1 or 2 which is fine especially on a blind scan. Some boxes are real touchy on the frequency (my CS8000 is like that)

That is weird on the channel name. Havent seen it do that very often where it lists a generic name versus the actual name (when there actually is a name)

 

[BarneyBean]

A satellite scan might be usefull on something like G10 where very little changes from day to day, however I still blind scan it because a few channels will pop up.