|
|
|
Who's Online
There currently are 5598 guests online. |
|
Categories
|
|
Information
|
|
Featured Product
|
|
|
 |
|
|
There are currently no product reviews.
 ;
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.
;
Excellent printing quality.
A complete and very usefull service manual with all details.
GREAT SERVICE AT VERY LOW PRICE!
A+++++++++++++++++++++++++
 ;
manual excelente completo , diagramas y esquemas bien presentados y buena calidad de imagen.
;
muy buen manual completo de buena calidad de impresion preciso y detallado , muy útil para la reparación.
;
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.
1-A. Preliminary/Final Checking and Alignment of Tape Path
Purpose: To make sure that the tape path is well stabilized. Symptom of Misalignment: If the tape path is unstable, the tape will be damaged. Note: Do not use an Alignment Tape for this procedure. If the unit is not correctly aligned, the tape may be damaged. 1. Playback a blank cassette tape and check to see that the tape runs without creasing at Guide Rollers [2] and [3], and at points A and B on the lead surface. (Refer to Fig. M3 and M4.) 2. If creasing is apparent, align the height of the guide rollers by turning the top of Guide Rollers [2] and [3] with a Guide Roller Adj. Screwdriver. (Refer to Fig. M3 and M5.)
Guide Roller [2] Guide Roller [3]
3. Check to see that the tape runs without creasing at Take-up Guide Post [4] or without snaking between Guide Roller [3] and AC Head. (Fig. M3 and M5) 4. If creasing or snaking is apparent, adjust the Tilt Adj. Screw of the AC Head. (Fig. M6)
Azimuth Adj. Screw
AC Head X-Value Adj. Screwdriver
Tilt Adj. Screw
Fig. M6
1-B. X Value Alignment
Purpose: To align the Horizontal Position of the Audio/Control/ Erase Head. Symptom of Misalignment: If the Horizontal Position of the Audio/Control/Erase Head is not properly aligned, maximum envelope cannot be obtained at the Neutral position of the Tracking Control Circuit. Fig. M3 1. Connect the oscilloscope to TP301 (C-PB) and TP513 (CTL) on the Main CBA. Use TP302 (RFSW) as a trigger. 2. Playback the Gray Scale of the Alignment Tape (FL8NW) and confirm that the PB FM signal is present. 3. Set the Tracking Control Circuit to the center position by pressing CH UP button then � PLAY � button on the unit. (Refer to note on bottom of page 2-3-4.)
AC Head
A
B Take-up Guide Post [4]
Lead Surface of Cylinder
Tape
Fig. M4
4. Use the X-Value Adj. Screwdriver so that the PB FM signal at TP301 (C-PB) is maximum. (Fig. M6) 5. Press CH UP button on the unit until the CTL waveform has shifted by approx. +2msec. Make sure that the envelope is simply attenuated (shrinks in height) during this process so that you will know the envelope has been at its peak.
Correct
Guide Roller Tape
Incorrect
Take-up Guide Post Tape
Fig. M5 2-3-3 U27NMA
|
|
|
> |
|
