Tascam DA-98HR Service Manual

Also see for DA-98HR: Setup guide Owner's manual

Tascam DA-98HR Service Manual Manual pdf 38 page image

385-6. Playback equalizer adjustment5-6-1. Checks in Normal mode1. ME tape1) Load Sony ME tape.2) Connect the oscilloscope to TP3 (RF A-HEAD) on theRF PLAY PCB , then set the oscilloscope range to 500mV AC, 50 nsec.3) Set REC FUNCTION ON (All channels) and execute for-mat recording in HR mode.4) Rewind and play the tape, and observe the eye pattern ofA-HEAD.5) Adjust R91 on RF PLAY PCB so that the 3.1 MHz wave-form is almost flat at top and bottom as shown in Photo-3.∗ Photo-2 shows the eye pattern when the oscilloscope isset to the 50 nsec/div. range.∗ Photo-3 shows the eye pattern when the oscilloscope isset to the 100 nsec/div. range.6) Similarly, connect the oscilloscope to TP4 (RF B-HEAD)on the RF PLAY PCB, then observe the eye pattern of B-HEAD.For adjustment, use R92 on the RF PLAY PCB.2. MP tape1) Load Sony MP tape.2) In the same way as in 1 (adjusting the equalizer using anME tape), adjust R93 (A-HEAD) and R94 (B-HEAD) onthe RF PLAY PCB.5-6-2. Checks in Confidence modeSet the Confidence mode on, and perform the same check as dis-cussed in 5-6-1. (The same check, but test points and adjust-ments not on RF PLAY PCB, but on RF REC PCB.)