Gain on a sounder

[reelchippy]

What is it ? What does it do ? cheers

[seamonkey]

Think hearing aid...turn it up you hear more sounds, down you hear less. the sounder converts those sound signals into a graphical display. Too high and you'll "hear" all the rubbish in the water...too low you won't hear what you want.

Bit of a balancing act really.

Cheers
SM

[plaztix]

is it the same as sensitvity in a cheap sounder? Mines just the bottom of the range eagle and it doesn't have gain just sensitivity.
Want to get something better but it does the trick atm.

[marco]

is it the same as sensitvity in a cheap sounder? Mines just the bottom of the range eagle and it doesn't have gain just sensitivity.
Want to get something better but it does the trick atm.

yes it is the same as sensitivity

[mik01]

i just read 'depth sounder secrets' and one tip was to always have sensitivity or gain set to max. the theory is that you WANT to see everything down there.

[dogsbody]

Just say your in 40ft of water and you want to fish in the bottom 10feet set the gain so that the bottom 10 feet or there abouts is showing. That way you'll get the max out of what you want to see.


Dave.

[croangler]

i have a furuno ls4100

at the moment my gain is set at 2 or 3 (shallow water) as soon as i set the gain higher than 2 or 3, my screen becomes totally dark.

i heard that you should set the gain high and set the clutter high as well.

[plaztix]

Just say your in 40ft of water and you want to fish in the bottom 10feet set the gain so that the bottom 10 feet or there abouts is showing. That way you'll get the max out of what you want to see.


Dave.

Wouldn't that be the zoom that you adjust?

[dogsbody]

No, when you turn up the gain it appears like flakes coming down from the top of your screen the higher you set it the darker from the top it becomes. Take a look at the sticky of sounder readings there are plenty of pics there.

(disregard the outline) In the pic i borrowed you can see down to 15 and the fish below if you were to increase the further down this would come same as if you decreased the higher this would become.



Dave.

[Dr Squid]

Think hearing aid...turn it up you hear more sounds, down you hear less. the sounder converts those sound signals into a graphical display. Too high and you'll "hear" all the rubbish in the water...too low you won't hear what you want.

Bit of a balancing act really.

Cheers
SM

Pretty much on the money with that one



i just read 'depth sounder secrets' and one tip was to always have sensitivity or gain set to max. the theory is that you WANT to see everything down there.

Gain is the sound Amplifier not the "valve" that lets the sound in. It sets the level of amplification of the received sound signal(which contrary to popular belief is a constant level) that is being fed into the processing unit on the sounder. You'll notice that a yellow return on low gain will show as red and new light blue returns will appear when the gain is turned up significantly higher. If you've ever used a loudhailer think of it(gain) in this sense:

When you have the hailer turned down low the sound of your voice only has to be amplified a little bit so it comes out the horn quiet cleanly and clearly, but people far away will find it hard to hear. If you wind it up to eleven(for all you rockers out there::)) the sound coming out the horn will be quite distorted(or containing a lot of "noise")to some one close by but to those further away the noise will have dissipated significantly because it softer than the main signal being broadcast and be a lot clearer.

Basically if you turn the gain up to amplify softer noises in deeper water you start getting distortion noise off the louder, closer, returns. This is why the red band at the top of the screen (call main bang) gets thicker when you turn up the gain.

I'm not sure if the 1650 has it but the newer furuno sounders( FCV-620, FCV-585, FCV-1100L) have whats called "TVG" or time varied gain(i think it's furuno specific as I'd never come across it on any other branded unit I'd carried). What it does is instead of blanket amplifying the returned signal as one, the unit will use low levels of gain for closer returns, medium levels of gain for medium distance returns and high level of gain for long distance returns. This can be adjusted depending what depth you're in. It' basically cleans up a lot of the noise higher up in the sounder column and you'll find that you actually use less gain and get better results.

*phew* now I'm going to get a beer :)

[plaztix]

No, when you turn up the gain it appears like flakes coming down from the top of your screen the higher you set it the darker from the top it becomes. Take a look at the sticky of sounder readings there are plenty of pics there.

(disregard the outline) In the pic i borrowed you can see down to 15 and the fish below if you were to increase the further down this would come same as if you decreased the higher this would become.



Dave.

So its just basically adjusting the blacked out section to show with maximum detail whats below the clutter to suit the depth your fishing and where the fish are.

[mik01]

I might add that it was also recommended to adjust the depth reading to manual once you have reached an area and turned the sensitivity up.

[dogsbody]

So its just basically adjusting the blacked out section to show with maximum detail whats below the clutter to suit the depth your fishing and where the fish are.


Spot on mate.



Dave.

[polky]

mik01 bud sounds like you have read the sounder secrets from Rick Huckstepp. I purchased it a couple of weeks ago, opened up a whole new world when using a sounder. All in all a very helpfull read. Polky.

[mik01]

mik01 bud sounds like you have read the sounder secrets from Rick Huckstepp. I purchased it a couple of weeks ago, opened up a whole new world when using a sounder. All in all a very helpfull read. Polky.

spot on mate.
learnt a fair bit I never knew. definitely worth a read