Power try machine, Dianyuan power indicates lamp bright, but heard not to following electrical sucking collection sound, judge amplifier Board Shang has "fault", opened cover overhaul, plus or minus voltage normal, measuring amplifier output no DC voltage, following electrical not sucking collection should is protection circuit problem, due to protection circuit and no several original, with with resistance method individually measurement following electrical around drive circuit each components, but didn't found has damaged original.YbPservice manual download site
Instead voltage method, measuring following electrical drive tube set electrode has 24V, no base very voltage, Shun circuit ahead check, found drive base very except by controlled Yu amplifier output end and plus or minus Dianyuan power outside, also has along control signal from Yu amplifier tube front of two a 55,513 very tube, according to circuit analysis this two pipes is up overload protection role of, due to distance other protection circuit components compared far, so a began no note, measurement right channel of 5551bc very has breakdown, After replacing the power on relay makes a snap sound, try working back to normalYbPservice manual download site