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Our Community => Personal Pages => RGecy => Topic started by: Doug Johnston on October 28, 2010, 04:20:45 AM

Title: 998c SI - Chart Speed Setting
Post by: Doug Johnston on October 28, 2010, 04:20:45 AM
Could someone please help me with chart speed. I saw a YouTube video the other day said use boat speed to determine chart speed.    i.e. 4 mph boat speed = chart speed of 4,  2 mph boat speed = chart speed of 2.
Any help on this subject would be appreciated. Thanks
Title: Re: 998c SI - Chart Speed Setting
Post by: Jolly Roger on October 28, 2010, 07:19:43 AM
Hi Doug,
the video advice is a good point to start from.
For quick wreck hunting runs I prefer the chart speed a notch higher than the boat speed, because the details of the seaground appear stretched and therefore bigger on the display.

A way which is a bit more time consuming to check if the boat speed and the chart speed are right: If you have a known wreck or other feature on the seafloor where the exact length is known. Just drive along side of it with different chart and boat speeds and make records of your runs.
Write down each run or use the sonar menu to display your settings while recording. Then watch your records with Hummviewer and use the "measure distance/length" tool of Hummviewer's utilities.

If the length of the object in the record is the same like in real, you have your right chart speed to the corresponding boat speed.

Hope this helps!

Regards / Harry
Title: Re: 998c SI - Chart Speed Setting
Post by: Doug Johnston on October 30, 2010, 07:03:59 AM
Thanks, Harry

Your advice will help - I'm a little data orientated anyway being the director of technical support for a natural gas compressor packager.

I stopped fishing for about 20 years, work, family, etc.
So I'm way behind where you guys are understanding all this new tech stuff.
It is unbelievable how far HB have came from the old flasher I had in 1982.
Title: Re: 998c SI - Chart Speed Setting
Post by: Jolly Roger on October 30, 2010, 04:34:10 PM
I hear you Doug,

I was blown away as well, when I got my unit last year in spring. It's quite a bit to learn and to get used to, but it's really worth the effort. Just hang in there for the first couple of weeks and play with your unit. You'll get used to it and then addicted, hehe. and if you have questions, here's the right place to ask. The forum was a bit lame during the summer, but it will pick up again now as people will be more on their PCs when the days are getting shorter.

Regards / Harry
Title: Re: 998c SI - Chart Speed Setting
Post by: Doug Johnston on October 31, 2010, 06:22:42 AM
Your right Harry,
I'm already addicted. I'm been back in coves I thought I knew pretty good with my old HB 575 Q-beam. I didn't have a clue what all was down there.

I guess if I had made 25 runs up and back I could have found most of it, but when you have limited fishing time it's hard to take that time.

I want to learn as much as possible about HB SI. To great of an asset not to take the time to learn ever thing I can to maximize it's benefits.

Thanks again. 
Title: Re: 998c SI - Chart Speed Setting
Post by: RGecy on October 31, 2010, 09:52:32 PM
Doug,

I usually dont adjust mine unless I am going slower or faster than normal.  Basically I keep my chart speed around 5 and usually troll along at 4 to 6 mph.  This gives very nice results.

If you travel slower, say with a trolling motor, you may want to keep your set lower. 

Good Luck,

Robert
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