User manual LOWRANCE X-15A PAPER GRAPH

[. . . ] the 2nd key and then press the "7" key. The paper speed will im- To turn this feature on, simply press the 2nd key, then press the "4" key. The paper speed will immediately slowdown, signifying that the function is enabled. To turn the Alternate Transmit and Print feature off, simply press mediately speed up, signifying that the function has been turned oft. [. . . ] This is called SurfaceClutter and is caused by algae and plankton, air bubbles caused by wave action or boat wakes, bait fish, or tempera- ture inversions. The surface clutter markings can be reduced or eliminated by using the MARKJSCC control key on the front panel keyboard. To use the SCC, press key 1 thru 4 and then the MARK/SOC key. 1 has a minimum effect on surface clutter, 4 has the maximum effect on reducing surface clutter. The amount of SCC that is used is printed at the bottom of the chart paper. If one level of SOC is used, then S-i is printed. Two levels, S-2, etc. The effecton surface clutter should immediately be seen. Use only the amount of SOC required to reduce the clutter, as fish signals can be eliminated by using this method, also. If you wish to turn the SOC function OFF, simply press 0-MARK/SOC and the SOC function will be disabled. Example: ENTER Press: 2 - SCO Result: A SOC LEVELOF 2. Depth C, , , Angle I 14 L. 1, 0, It" 12, 0 it it gt III g 0:30 53 70 Diameter I I I 50' 20 100' zoo' 20'at: 8°at3db III BASIC OPERATION On-Off and SensitivityControl -- Rotate the Sensitivity knob clockwise to turn the unit on. The Sensitivity knob works much like the volume control on a radio, that is, weaker signals will be detected with higher settings of the knob. When cruising, or at other times when just simple bottom contour information is desired, the Sensitivity setting can be low. In deep water or over soft, muddy bottoms, (which produce weak echos), the setting will have to be higher. 4 (See Figure 37. l2-------- I-- Figure 37 SCC "2" _17 PDF compression, OCR, web-optimization with CVISION's PdfCompressor wheels by reversingthe procedure used to remove the old one. BE SURE the fingers of the new stylus are pointed UP. Latch both catches at the top of the unit. MAINTENANCE NOTE: The stylus may be damaged if it is in front of the platen when the platen assembly is pulled down. Always move the stylus to the back side of the platen when changing the paper rolls. Remember to move the belt down to remove the stylus. Black carbon dust is created during the recording process. Use a soft, oil-free rag to clean the viewing door and metal platen behind the paper. Low pressure compressed air may be used to blow dust out of the case and away from moving parts if the air is dry and free of oil. [. . . ] (Note: This may also be adjusted with the unitturned OFF. Adjust the control, then remove the screwdriver and turn power back ON. Repeat until the zero line is in the desired position. ) 0-- 10 -- -4 20 -- 30 -- -v-, 40-- 50 -- so -- ZERO ADJUST Occasionally, when changing the stylus or stylus belt, the zero line does not print at the same place near the top of the chart paper. IV HOW TO READ GRAPHS "Arched Signatures" X-15A is that it can record individual fish with a characteristic arched mark that separatesthem from their stationary surroundings. The distance to a fish when it moves into the sonar's cone of sound is shown as "A". [. . . ]