SOUNDER PC ... THE WORLD'S FIRST PC BASED
RECREATIONAL FISH FINDER / DEPTH SOUNDER.

Using DSP technology for unprecedented performance
when compared to conventional fish finders.

Developed by Cruz-Pro NZL, this DSP technology reduces the output power
requirement up to 10 times that of conventional units...
environmentally friendly lower power that doesn't scare away sensitive species,
all with greater accuracy from shallow water to depths of up to 1,000 feet. 

See what Practical Sailor says about Sounder PC

World's first depth sounder & fish finder for PC's Full Screen Color Display on any size PC monitor Complete Windows based software and guide on CD Multiple display/tracking modes and data logging Advanced Digital Signal Processing (DSP) design Highly accurate to 1000 foot depth at 200 KHz Hull mount transducer standard, transom optional Low power consumption, compact, easy installation

$799.00 Announcing the world·s first PC based depth sounder and fish finder. The SounderPC depth uses the latest digital signal processing (DSP) technology for efficient, powerful and highly accurate performance.  Standard RMS power output ranges from 1.3 to 320 watts RMS, depending on transducer element impedance and depth. Due to advanced DSP technology, the Effective Processed Power (EPP) of the SounderPC is about 20 times the RMS power output found in a typical analog type depth sounder.

In order to improve deep water response, depth sounder technology has historically tried three options:

1)  Increase Power- 
The brute force approach.  This works but requires the use of a physically larger transducers and transducer elements to keep the sound pressure below the water cavitation level (you don't break the transducer if you increase power too high, but start to form air bubbles under the transducer just like a boat propeller cavitates the water if you spin it too fast). The air bubbles prevent proper operation.   More power on depth sounders results in bigger, more expensive depth sounders requiring bigger, more expensive transducers.

2)  Use Lower Frequencies-
The lower frequencies are attenuated less and penetrate deeper.  This also works but suffers from loss of resolution.    Higher frequencies will produce returns from smaller targets.  At 200kHz for example, targets as small as 1/4 inch in diameter will generate an echo, whereas at 15kHz, targets must be at least 2 inches in diameter to produce a detectable echo.  Lower frequency crystals are also physically larger and typically more expensive.

3) Improve Sensitivity- 
Reduce noise by filtering the return signal with a very narrow band filter. In typical analog depth sounders, narrow band filters are difficult and expensive to manufacture and require an Automatic Gain Control (AGC) and careful tuning and adjustment and a LOT of expensive parts.   If you don't use expensive parts, the filter drifts with temperature and vibration and you lose the performance.

The amazing, new SounderPC utilizes DSP technology to dramatically improve sensitivity in a cost effective and reliable manner. The SounderPC does very little filtering, mostly amplification then transmits data straight into the computer as a series of 1's and 0's.  The narrow band filtering is done in software which does not require an AGC or a lot of expensive components and doesn't drift with temperature or vibration and requires no factory adjustments.  You can use smaller (cost effective) transducers and see smaller targets with higher resolution.

The SounderPC is extremely accurate at high boat speeds because it is unaffected by ringing due to transducer slap & buffeting.  The ·smart· DSP technology actually rejects signals caused by buffeting by not transmitting data at the transducer's natural ringing frequency and only responding to signals at the transmitted frequency.   Note that ALL standard analog depth sounders suffer from transducer ringing due to slap & buffeting.  It's impossible to avoid this in analog AGC thresholding type systems.

Once locked onto the bottom, the SounderPC·s smart DSP technology is practically unaffected by other nearby depth sounders (even at the same frequency) for the same reasons as above.  Because the SounderPC uses less power, it also has less effect on other nearby depth sounders. At depths to about 300 feet the SounderPC only uses about 1.3 watts, which is why you can't hear transducer "click" of older technology. 

(click here for Sounder PC Specifications)