Analysis of maintenance: protect led is flashing after turning on, loudspeaker protection relays do not snap. Measuring-point voltage is 0V, normally. Midpoint of the lines directly connected to the speaker output and ground, sounds normal, indicating that the speaker protection circuit itself is faulty.6fWservice manual download site
6fWservice manual download site
The protection circuit is shown in Figure 1. R2 top measuring voltage 50V but lower R2 voltage is 0V, suspected of R2 (390 ω) open, remove the measuring its resistance 410k ω, normal. Measure the resistance to Earth V1 in road and found that the collecting electrode resistance of only 150 ω to ground, removed V1, V1. Remove V2 and found it b-c with forward and reverse resistance around 180 ω, replace the V2 trial and subsequent electrical snap a few seconds, and troubleshooting. R2 top voltage measurement at the time, has turned to 18V.6fWservice manual download site