Philips DVDR3510V-05, DVDR3510-31, DVDR3510-51, DVDR3510-58 – How to take out the cassette tape at emergency, mechanical alignments and more

 

 Many electrical and mechanical parts in this chassis have special characteristics. These characteristics often pass unnoticed and the protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts that have these special safety characteristics are identified in this manual and its supplements; electrical components having such features are identified by the mark " ! " in the schematic diagram and the parts list.. The use of substitute replacement parts that do not have the same safety characteristics as specified in the parts list may create shock, fire, or other hazards.

Manual Procedure to remove the tape from the loader (How to take out the tape at emergency)

 Immediate action must be done to remove the Video Cassette on the set manually as described below :
Note : Item number refers to the Deck Parts List in VCR Module (12NC:2422 549 01124) unless otherwise stated

* Turn the B525 (LDG Belt MK11 ) in the direction indicated by the arrow below in figure.

* Upon hearing the click sound , the Clip[B587] holding the VCR will be released as shown.

* The tape will be slackened as shown.

* The video cassette slowly reversed and raised to loading position.

* Fold the slack of the video by hand to minimize damage by the front dust cover of Video cassette. The front cover upon approaching the B354 & B355 position will be closed and comes out of the Door Flap(112 of exploded view of DVDR3430V).

* Remove the cassette as you normally do from the front loading position.

Mechanical alignment procedures

Method for Manual Tape Loading - Unloading
To load a cassette tape manually:
1. Disconnect the AC plug.
2. Remove the Top Case and Front Assembly.
3. Insert a cassette tape. Though the tape will not be automatically loaded, make sure that the cassette tape is all the way in at the inlet of the Cassette Holder. To confirm this, lightly push the cassette tape further in and see if the tape comes back out, by a spring motion, just as much as you have pushed in.
4. Turn the LDG Belt in the appropriate direction shown in Fig. M1 for a minute or two to complete this task.
To unload a cassette tape manually:
1. Disconnect the AC plug.
2. Remove the Top Case and Front Assembly.
3. Make sure that the Moving guide preparations are in the Eject Position.

4. Turn the LDG Belt in the appropriate direction shown in Fig. M1 until the Moving guide preparations come to the Eject Position. Stop turning when the preparations begin clicking or cannot be moved further. However, the tape will be left wound around the cylinder.

5. Turn the LDG Belt in the appropriate direction continuously, and the cassette tape will be ejected.  Allow a minute or two to complete this task.

Method to place the Cassette Holder in the tape-loaded position without a cassette tape
1. Disconnect the AC Plug.
2. Remove the Top Case and Front Assembly.
3. Turn the LDG Belt in the appropriate direction shown in Fig. M1. (The Cam Gear in Fig. M2 rotates.) Release the locking tabs shown in Fig. M1 and continue turning the LDG Belt until the Cassette Holder comes to the tape-loaded position.
Allow a minute or two to complete this task.

Preliminary - final Checking and Alignment of Tape Path

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.)

3. Check to see that the tape runs without creasing at Take-up Guide Post [4] or without snaking between Guide Roller [3] and ACE Head. (Fig. M3 and M5)

4. If creasing or snaking is apparent, adjust the Tilt Adj. Screw of the ACE Head. (Fig. M6)

X Value Alignment

If the Horizontal Position of the ACE Head is not properly aligned, maximum PB FM envelope cannot be obtained at the preset position of the Tracking Control Circuit.
1. Connect the oscilloscope to TP301 (C-PB) and TP503 (CTL) on the Main CBA. Use TP504 (RFSW) as a trigger.
2. Playback the Gray Scale of the Alignment Tape (9965 000 14515) and confirm that the PB FM signal is present.
3. Set the Tracking Control Circuit to the preset position by pressing “CH UP” button and then “VCRPLAY” button on the unit.
4. Use the Flat Screwdriver so that the PB FM signal at TP301 (C-PB) is maximum. (Fig. M6)

5. To shift the CTL waveform, press “CH UP” or “CH DOWN” button on the remote control unit. Then make sure that the maximum output position of PB FM envelope signal becomes within ±2ms from preset position.

6. Set the Tracking Control Circuit to the preset position by pressing “CH UP” button and then “VCRPLAY” button on the unit.

Checking/Adjustment of Envelope Waveform

To achieve a satisfactory picture, adjust the Guide Rollers so that 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 TP301 (C-PB) on the Main CBA. Use TP504 (RF-SW) as a trigger.
2. Playback the Gray Scale on the Alignment Tape (9965 000 14515). Set the Tracking Control Circuit to the preset position by pressing “CH UP” button and then “VCR-PLAY” button on the unit. Adjust the height of Guide Rollers [2] and [3] (Fig. M3, page 4-
6) 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. M8, adjust the height of Guide Roller [2] (Refer to Fig. M3) so that the waveform looks like the one shown in Fig. M10.
4. If the envelope is as shown in Fig. M9, adjust the height of Guide Roller [3] (Refer to Fig. M3) so that the waveform looks like the one shown in Fig. M10.

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. 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 on the unit alternately, to check the symmetry of the envelope. Check the number of pushes to ensure preset position. The number of pushes of the “CH UP” button on the unit to achieve 1/2 level of envelope should match the number of pushes of the “CH DOWN” button on the unit from center. If  required, redo the “X Value Alignment.

Azimuth Alignment of Audio/Control - Erase Head

To correct the Azimuth alignment so that the Audio/Control/Erase Head meets tape tracks properly.
Symptom of Misalignment
If the position of the Audio/Control/Erase Head is not properly aligned, the Audio S/N Ratio or Frequency Response will be poor.
1. Connect the oscilloscope to the audio output jack on the rear side of the deck.
2. Playback the alignment tape (9965 000 14515) and confirm that the audio signal output level is 8kHz.
3. Adjust Azimuth Adj. Screw so that the output level on the AC Voltmeter or the waveform on the oscilloscope is at maximum. (Fig. M6)
Note: Upon completion of the adjustment of Azimuth Adj. Screw, check the X Value by pushing the “CH UP” or “CH DOWN” buttons on the unit alternately, to check the symmetry of the envelope. Check the number of pushes to ensure preset position. The number of pushes of the “CH UP” button on the unit to achieve 1/2 level of envelope should match the number of pushes of the “CH DOWN” button on the unit from center. If required, redo the “X Value Alignment.”

Checking and Alignment of Tape Path during reversing
Purpose: To make sure that the tape path is well stabilized during reversing.
Symptom of Misalignment.   If the tape path is unstable during reversing, 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. Insert a blank cassette tape into the tray and set the unit to REV. Then confirm if the tape has been curled up or bent at the Take-up Guide Post[4] or REV Post[5]. (Refer to Fig. M11 and M12.)
2. When the tape has been curled up or bent, turn the alignment screw to adjust the height of REV Post. (Refer to Fig. M11 and M13.)