Notes on VCR Failure Diagnosis and Repair

Contents:

	Table of Contents
	Chapter 1) About the Author & Copyright
	Chapter 2) Introduction
	2.1) Entertainment - then and now
	2.2) VCR repair
	2.3) Repair or replace
	Chapter 3) Video Recording Technology
	3.1) Helical scan video recording
	3.2) VHS video
	3.3) VHS audio
	3.4) VCR servo systems
	3.5) Video Special effects
	3.6) For more information on VCR technology
	Chapter 4) VCR Placement, Preventive Maintenance, and Rental Tapes
	4.1) General VCR placement considerations
	4.2) Preventive maintenance (PM)
	4.3) Rental tape considerations
	Chapter 5) VCR Maintenance and Troubleshooting Guide
	5.1) Safety
	5.2) Troubleshooting tips
	5.3) Test equipment
	5.4) Cassette cheaters
	5.5) Test tapes
	5.6) Getting inside a VCR
	5.7) Why does my VCR shut down or behave strangely when I remove the cover?
	5.8) Getting built up dust and dirt out of a VCR
	5.9) What to do if a tiny tiny part falls into the VCR
	Chapter 6) VCR Tape Transport Fundamentals
	6.1) Parts of the tape transport in a VCR
	6.2) Most common problems
	6.3) General guide to VCR cleaning and rubber parts replacement
	6.4) Lubrication of a VCR
	6.5) Head demagnetizing
	Chapter 7) Cassette and Tape Loading Problems
	7.1) Cassette loading and eject problems
	7.2) Ejecting a cassette from an uncooperative VCR
	7.3) VCR is confused - will not eject non-existent tape
	Chapter 8) Fast Forward and Rewind Problems
	8.1) VCR will not fast forward and/or rewind
	8.2) VCR aborts fast forward or rewind
	8.3) Tape rewinders
	Chapter 9) Play and Record Mechanical Problems
	9.1) VCR refuses to record
	9.2) VCR aborts play or record during startup or shortly thereafter
	9.3) VCR aborts play or record at random times or near end of tape
	9.4) VCR eats tapes
	9.5) Tape loop hanging from cassette when ejected after play or record
	9.6) Tape sticks to head drum
	9.7) Video head drum stops or slows during play or record
	Chapter 10) General Control Problems
	10.1) VCR is alive but will not do anything
	10.2) Erratic behavior in various modes
	10.3) VCR mode (sensor) switches
	10.4) Mechanical relationships in VCRs
	10.5) VCR does not work after cassette was forcibly removed
	10.6) The VCR is failing the power-up sequence
	10.7) VCR displays DEW warning
	10.8) VCR shows LOCKED in the display
	10.9) VCRs with Alzheimer's Disease
	10.10) VCR has gone whacko
	10.11) VCR forgets settings following power failure
	Chapter 11) Play and Record Control Problems
	11.1) VCR randomly switches speeds, tracking problems, and muddy sound
	11.2) VCR plays but at fast forward speed (or beyond)
	11.3) Tape edge gets creased and/or random switching between speeds
	11.4) Recording stops at random times on previously used tapes
	11.5) Record (or play) stops after 15 minutes (or 30 minutes, etc.)
	Chapter 12) Video Play and Record Problems
	12.1) Video playback problems
	12.2) Video record problems
	12.3) Snow on one or more speeds
	12.4) Jumpy picture in play
	12.5) Incorrect frame alignment or bad video for part of frame
	12.6) Rainbow pattern in recordings made over previously recorded tapes
	12.7) Flag waving
	Chapter 13) Audio Problems
	13.1) Poor quality sound on non-HiFi VCR
	13.2) Excessive flutter on VHS linear audio playback
	13.3) Previous (non-HiFi) audio is not erased on new recordings
	13.4) Poor quality sound on HiFi VCR
	13.5) Squealing noise from VCR in certain modes
	13.6) High pitched whine from inside VCR
	Chapter 14) Signal and Interference Problems
	14.1) VCR color problems
	14.2) RF signal problems
	14.3) VCR will not tune broadcast or cable
	14.4) Interference as parallel horizontal lines when playing tape
	14.5) Firing (static) lines in picture during playback
	Chapter 15) General System Problems
	15.1) Multiple system problems
	15.2) Power supply problems - unit totally dead/major system problems in all modes
	15.3) VCR power supplies
	15.4) Internal fuse blew during lightening storm (or elephant hit power pole)
	15.5) Use of surge suppressors and line filters
	Chapter 16) Miscellaneous Problems
	16.1) VCR poops out after a couple of hours
	16.2) VCR was dropped
	16.3) VCR or camcorder went to the beach (sand and/or surf)
	16.4) Dead remote control units
	16.5) Recovering damaged or broken tapes
	16.6) Cassette rewinder problems
	Chapter 17) A Few Model Specific Problems
	17.1) Dead Clock in Hitachi manufactured VCR
	17.2) JVC tracking problems and dropped parts
	17.3) Panasonic and clones switching power supplies
	17.4) Late model Sony VCR munches tape on eject
	17.5) Symphonic/Funai brand vcr won't rewind or fast forward
	Chapter 18) Video Heads and Upper Cylinders
	18.1) What is a Video head?
	18.2) Are your videos heads really bad?
	18.3) Need for video head cleaning
	18.4) Video head cleaning technique
	18.5) Advanced video head testing techniques
	18.6) Where to obtain replacement video heads
	18.7) Video head replacement technique
	18.8) Can I substitute a video head from another VCR?
	Chapter 19) Tape Path Alignment and Backtension Adjustment
	19.1) General tape path alignment problems
	19.2) Adjustment of A/C head - problems with tracking or sound (linear audio)
	19.3) Roller guide height adjustment
	19.4) Likely causes for sudden change in tracking behavior
	19.5) Backtension adjustment
	Chapter 20) VCR Sensors and Tape Counters
	20.1) Tape start/end sensors
	20.2) Start/end sensor testing
	20.3) Tape counters
	20.4) Reel rotation sensors
	20.5) Reel rotation sensor testing
	Chapter 21) Motors and Rotors
	21.1) Types of motors in VCRs
	21.2) Repairing small motors
	21.3) Capstan problems
	Chapter 22) Items of Interest
	22.1) Why is a tracking control needed
	22.2) Old clunkers and the march of technology
	22.3) Can I add an S-Video input to my VCR?
	22.4) Can a VHS VCR record single video frames at a time?
	22.5) Why is a special VCR needed for multiple video standards?
	22.6) What is a delay line and where is it used?
	22.7) Why are there so many different design for VHS transports?
	22.8) Service center honesty?
	22.9) IR detector circuit
	22.10) VHS specifications
	22.11) Luminance Specifications for various VCR technologies
	Chapter 23) Service Information
	23.1) Advanced VCR troubleshooting
	23.2) FCC ID Numbers of VCRs
	23.3) Determining belt, tire, and pinch roller specifications
	23.4) Interchangeability of components
	23.5) Suggested Parts Suppliers
	23.6) Other Sources

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