(/JI-ZWI ~t;::J....,C-loer:I I-ow-lw4-3-27. NORMAL AUDIO BIASCURRENT ADJ.BOARD AUDIO C.B.A.TP NC HEADADJ S-VHS:VR4007(CH1 )(A-1 ),VR4008(CH2)(A-~TAPE S-VHS, VHS BLANK TAPEINPUT COLOUR BAR SIGNAL (LINE)MODE RECM.EQ V.T.V.M.S-VHS CH1: 5.OmVrms ± 0.1 mVrms,SPEC CH2: 5.OmVrms ± 0.1 mVrmsVHS CH1: 4.0mVrms ± 0.3mVrms,CH2 4.OmVrms ± 0.3mVrms1. Supply the colour bar signal to video input.2. Insert the S-VHS blank tape and place the deck inREC mode.3. Connect the V.T.V.M. to the A/C head as shown inFigure E26.4. Adjust VR4007 (CH1), VR400B (CH2) so that thelevels become 5.0mVrms ± 0.1 mVrms.5. Insert the VHS blank tape and place the deck inREC mode.6. Confirm the CH1 and CH2 levels are 4.0mVrms ±0.3mVrms.A/C HEAD1mVV1VV2CH1 CH2TPFigure E264-3-28. NORMAL AUDIO RECCURRENT ADJ.BOARD AUDIO C.B.A.TP AUDIO OUTPUT (CH1 ,CH2)TP4005(CH1 )(C-1), TP4006(CH2)(B-1)ADJ VR4005(CH1 )(C-1), VR4006(CH2)(D-11TAPE S-VHS BLANK TAPEINPUT 1KHz, -8dBv SINEWAVEMODE RECM.EQ V.T.V.M. (D.v.M.)SPEC S-VHS 0 + O.5dB VHS 0 +1.0dB[SET UP]S-VHS SW : ON1. Set the audio output select switch to NORM.2. Connect the V.T.V.Ms to the deck as shown inFigure E27. Note that only one channel will beadjusted at a time.3. Supply a 1KHz, -BdBv sine wave signal to theAUDIO INPUT (CH1).4. Place the deck in the REC mode with S-VHSmode.5. Adjust VR4005 (CH1) so that V.T.V.M. (2) readsapproximetely 0.5Vrms (1.41Vp-p) .6. Playback the recorded portion, and note theamount of difference between V.T.V.M. (1) and(2).7. Place the deck in the REC mode again, andreadjust VR4005 (CH 1) slightly, and repeat step 5,nothing the new dirfference.B. Repeat this "Record/Set/Note to Playback/Note"record and playback readings is minimized (OdBv± O.5dBv).9. Repeat the above procedure again for channel 2,using the other set of test points and VRs.DECK slVoToVoMoW IAUDIO OUT~~ AUDIO IN ~ SINEWAVE\ SIGNALTP4005 (CH1) GENERATORTP4006 (CH2)V.T.V.M.(2)Figure E274-12
