User manual AUDIOVOX AQUATRONICS MS250

[. . . ] 6 FADER KNOB Rotate this knob to left or right for desired sound balance from front to rear speakers. 7 DISPLAY 8 TONE BUTTON Press this button to adjust for high or low tone. 9 LO/DX BUTTON Press this button to change between local(LO)and distant(DX)reception. in some cases, changing the LO/DX setting will allow clearer reception of a desired station. [. . . ] This AC ripple noise is filtered by the boat battery when connected into the circuit , but when the battery is disconnected the amount of AC ripple noise can create major problems for audio products. Noise may result and the line fuse may fail Ignition systems Unwanted noise generated from ignition systems used to be a big problem. However, with more sophisticated filtering circuits designed into audio/video products, these problems are not as wide spread Changes in wire harnessing also has contributed to the decline of application problems. This will greatly reduce the potential for unwanted noise. AM ANTENNA TRIMMER ADJUSTMENT The antenna trimmer can be accessed through the small hole behind the cassette door (see diagram below). Tune radio to a weak station between 1200 and 1400 KHz AM ( If you cannot find a weak station in this range, tune to any other strong station, and adjust tuning slightly off station). Adjust trimmer for maximum volume. FRONT VIEW OF RADIO ANTENNA TRIMMER (NOTE: OPEN CASSETTE DOOR TO SEE THE ADJUSTMENT SCREW) SPECIFICATIONS 7''(W) x 2''(H) x 6-5/8''(D) 178mm x 50mm x 150mm 12VDC, Negative Ground 50Watts Max . Stereo Power Floating Ground type designed for 4 speakers use. May also be used with 2 speakers. Tuning Range: (AM)530-1710KHz (FM)88-108MHz Sensitivity: (AM) less than 25uV (FM) less than 5uV FM Stereo Separation: More than 23 dB Frequency Response: 50-10000Hz Wow & Flutter: Less than 0. 3% Size: Operating Voltage: Output Power: Output Wiring: CARE & MAINTENANCE Cassette Always check that the tape is tightly wound inside the take-up spool on the cassette. If the tape is loose, wind it with a six - sided pencil. Never use C-120 (120 minute) cassettes in this player. Never use cassette player when vehicle temperature is near or below freezing. Cleaning of Tape Head & Capstan Since tapes contain oxides, you will find a black residue builds up on the tape head and drive capstan ( inside cassette door ). These residues should be cleaned after 50-100 hours of accumulated tape operation . You can use a cassette cleaning cartridge available where ever stereos are sold. De-Magnetizing The movement of the magnetic tape head and metal parts cause a magnetic field to develop. We recommend you have the tape player demagnetized at least twice annually. You can purchase an inexpensive tape head demagnetizing tool to do this yourself. 3 "We have a complete line of audio and video products specifically designed for the Marine and RV market. [. . . ] FM RECEPTION FM reception can be received with a very limited antenna and strong local FM stations can be received without an antenna , depending on the circumstances. CONCLUSION: AM/FM reception is subject to the choice of an antenna and it's application. There can also be a variety of methods used to supply signal to both primary and secondary radios , but AM performance is the ultimate "test" Cause No 12VDC Possible Solution Check circuit fuse at source Check in-line fuse on power lead Power lead disconnected Ground connection disconnected Circuit fuse at source In-line memory lead fuse Check continuity of speaker leads to ground Check for proper speaker wiring Note: Radios have a sticker on them explaining wiring color code. [. . . ]