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Very quality copy of original service manual, which contains the circuit diagrams, PCB and lists of components, well as recommendation for calibration procedures of device, also everything else, that need for repair, tuning and use this oscilloscope.
All presented copies have high-resolution, so you can view all in detail.
This manual will very useful for simple owners and for repairers.
I recommend these manual, because myself is owner of Philips PM3216 and I need sometimes servicing these oscilloscope (principally calibrating).
Also, these document is an example of excellent design of technical documentation.
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Excellent printing quality.
A complete and very usefull service manual with all details.
GREAT SERVICE AT VERY LOW PRICE!
A+++++++++++++++++++++++++
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manual excelente completo , diagramas y esquemas bien presentados y buena calidad de imagen.
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muy buen manual completo de buena calidad de impresion preciso y detallado , muy útil para la reparación.
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The service manual is a good quality scan of the Panasonic NV-850, which is electrically identical to the Philips VR 6920, but mecanically just nearly.
5. To shift the CTL waveform, press [CH UP] or [CH DOWN] buttons on the remote control unit. Then make sure that the maximum output position of PB FM envelope signal become within ±2ms from preset position.
4. If the envelope is as shown in Fig. M8, adjust the height of Guide Roller [3] (Refer to Fig. M3) so that the waveform looks like the one shown in Fig. M9. 5. When Guide Rollers [2] and [3] (Refer to Fig. M3) are aligned properly, there is no envelope drop either at the beginning or end of track as shown in Fig. M9.
Good
FM envelope signal 2ms Center Position
Dropping envelope level at the beginning of track.
FM envelope output signal is adjusted at maximum.
CTL signal
Fig. M8
No Good
Dropping envelope level at the end of track.
FM envelope output signal is low.
Fig. M7
6. Set the Tracking Control Circuit to the preset position by pressing [CH UP] button on the remote control unit. and then [PLAY] button.
1-C. Checking/Adjustment of Envelope Waveform
Purpose: To achieve a satisfactory picture, adjust the PB FM envelope becomes as flat as possible. Symptom of Misalignment: If the envelope output is poor, noise will appear in the picture. The tracking will then lose precision and the playback picture will be distorted by any slight variation of the Tracking Control Circuit. 1. Connect the oscilloscope to TP (C-PB) on the Main CBA. Use TP (RF-SW) as a trigger. 2. Playback the Gray Scale on the Alignment Tape (FL8N --- 2 head model, FL8NW --- 4 head model). Set the Tracking Control Circuit to the preset position by pressing [CH UP] button and then [PLAY] button on the unit. Adjust the height of Guide Rollers [2] and [3] (Fig. M3, Page 2-3-3) watching the oscilloscope display so that the envelope becomes as flat as possible. To do this adjustment, turn the top of the Guide Roller with the Guide Roller Adj. Screwdriver. 3. If the envelope is as shown in Fig. M7, adjust the height of Guide Roller [2] (Refer to Fig. M3) so that the waveform looks like the one shown in Fig. M9.
Fig. M9
Envelope is adjusted properly. (No envelope drop)
Fig. M10
Note: Upon completion of the adjustment of Guide Rollers [2] and [3] (Refer to Fig. M3), check the X Value by pushing the [CH UP] or [CH DOWN] buttons alternately, to check the symmetry of the envelope. Check the number of pushes to ensure preset position. The number of pushes [CH UP] button to achieve 1/2 level of envelope should match the number of pushes [CH DOWN] button from center. If required, redo the �X Value Alignment.�
2-3-4
MK14NMA_FC
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