Sonic frontiers sfm 75 mk2 owners manual

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marked on the chassis. Insert the screwdriver into the corresponding bias control and watch the meter pointer as you slowly rotate your screwdriver clockwise. Adjust the control until the pointer indicates 50 on the meter. Now rotate the selector switch to the V6 position and rotate the V6 bias control clockwise to set the meter pointer at 50. Follow the same procedures for LV3 and LV4. Wait a few minutes and recheck the settings for all 4 output tubes. Once you have finished adjusting all 4 bias controls, return the selector switch to the OFF (centre) position. Your SFM-160 amplifier is now ready for use. NOTE:The red mark at the 50 point on the meter scale is the maximum recommended bias point for the KT99(a)/6550Aoutput tubes. Setting the bias meter to read in excess of this value will exceed the rated dissipation rating of the tubes and unnecessarily shorten your tube life with no redeeming sonic benefit. You may, if you wish, operate the tubes at the 40 mark for somewhat longer tube life. If you are unable to perform the previous adjustments, turn to the Trouble-Shooting section of this manual on Page 3. CLEANING The beautiful stainless steel (non-magnetic) finish of the chassis and transformer top covers will last for years. Aregular dusting with a soft, non-abrasive cloth will generally keep the finish looking like new. Fingerprints may be removed with a small amount of silicon spray, such as WD-40 TM. Be sure to apply any liquid into a soft cleaning cloth, not directly onto the chassis. At no time should you allow any liquids to drop onto the amplifiers; it may run into the electronic circuitry underneath and cause damage which will not be covered under your warranty! TROUBLE-SHOOTING GUIDE If at any time a SFM-160 amplifier fails to work, follow this simple checklist: 1. Make certain that the A.C. power cord is plugged in firmly, both at the A.C. wall socket and at the A.C. amplifier socket. 2. Make sure that you have biased the output tubes. 3. Remove the A.C. power cord at the amplifier and open the fuse hatch on the A.C. input socket. Check that: A.Aslo-blo fuse, with a rating of 5 amps 250V (0.25 x 1.25), is installed (or 2.5 Amp 250V (5mm x 20mm) for European and Asian versions). B.That the A.C. power fuse is intact and has not blown. 4. If the power line fuse has blown, replace it with a same size and type fuse of the same rating (5 Amp 250V. slo-blo - 100 to 120 Volt Countries / 2.5 Amp 250V. - 200 to 240 Volt Countries).