OPERATION, SAFETY, AND PROTECTION

In addition to recording and producing great video, every Beta VCR had to be smart. To keep on top of things, there were a number of sensors and switches whose job it was to monitor important operations. Integrated circuits used the information they provided to turn on the VCR, accept a cassette, control every tape motion, and handle all the various commands. Not only was this required for operation, but it was also necessary for protecting your precious tapes. All these components worked together to make possible the tape handling prowess and exceptional features for which the Beta format was famous. They were located throughout the VCR and are identified and described below.

BASIC OPERATION
Before anything happens.
1. Overload fuses: There are a number of these fuses located at critical points throughout the VCR. They protect its circuits from power surges that could cause damage to vital components. If the amperage or voltage going across the fuse becomes too high, it will open before a major meltdown can occur. Most of these are located in the power section where the various operating voltages are created. Others are positioned next to a group of circuits or a critical IC. Notation: These are single event protection devices and are not reversible. Their failure requires replacement (repair).
2. Overheat fuses: There are a number of solenoids in the VCR that perform various functions. Every one has a temperature and voltage-sensitive fuse wrapped within or next to its windings that will open if it gets too hot or too much voltage is applied. This cuts the power off to the solenoid and prevents possible combustion. Notation: These are single event protection devices that do not reverse. Their failure requires replacement (performed during repair).
3. ON/OFF button (switch): In the off mode, the VCR is basically a clock, but it has potential. Pressing the ON/OFF (or power) switch begins the basic operation of the VCR. Depending on the model, it can also be turned on by pressing the on/off button on the remote, by inserting a cassette, or pressing the SET TIMER button. Once the VCR is turned on, all the settings, functions, and features become accessible. It is now standing by to perform video magic. Pressing ON/OFF again stops all operation of the VCR unless it is in timer record mode. Notation: some models have separate buttons for ON and OFF.

ADVANCED OPERATION
All the sensors and detectors that are listed next ensure that everything performs correctly and that you have an outstanding Beta experience.
4. Cassette-detection switch: For front-loading VCRs, this switch recognizes that a cassette has been inserted and to start the loading process. If a cassette is inserted at an angle or is not placed far enough inward (to securely locate it inside the loading mechanism), the detection switch will not be activated, and loading will not begin. If the cassette is obstructed going in, after a set time interval, the cassette will be ejected. Notation: For proper loading, the cassette should be pushed gently inward near the center following it forward slightly with your fingers. This is so it goes in squarely, all the way forward, then down into the compartment. This follow-through allows the rubber cassette grippers on the sides of the loading assembly to securely capture the cassette. If it is discovered that there is an obstruction preventing forward engagement, it must be removed. Repair might be needed if the cassette continues to load improperly. For top-loading portable Betas, the detection switch activates when the cassette is all the way down and correctly seated upon the location bosses (or guide pins). Once in proper position, the tape will automatically be (safely) drawn from inside the cassette and into the tape path.
5. Cassette-down switch: This switch recognizes that the cassette has been received, traveled inward, and is now seated inside the tape compartment on the locating bosses (also called guide pins). Only then can tape threading begin. If there is an obstruction that prevents the cassette from going all the way down, this switch will not be activated and after about seven seconds, the threading attempt will be aborted. Failure will normally cause loading to reverse and the cassette to be ejected. If this problem continues, repair might be needed. Notation: For portables this function begins when the cassette is all the way downward and the lid is locked in the closed position.
6. End-of-threading switch: Once threading of the tape begins, the main processor allows approximately 3-5 seconds for tape threading to be completed. If this end-of-threading switch is not activated in this allotted time, threading will stop and then reverse, and the cassette will be ejected. This action usually is an indication that it could not be completed for some reason. Notation: If it continues to happen, correcting this problem usually requires repair.
7. Splice-avoidance routine: Once a cassette has been loaded, threaded, and secured in the tape path, the VCR uses the rewind stop sensor to detect if the foil end leader at the beginning of the tape has been drawn out from inside the cassette. This leaves the splice-to-tape joint out in harms way, and possibly onto the surface of the video drum. If the splice is out in the path, the VCR will perform the splice-avoidance routine. The take-up reel will rotate slowly forward and pull the tape and back into the cassette until the foil leader clears the end sensor. The video disk (heads) does not spin while this is being completed. Notation: This safety procedure prevents the splice between the foil leader and the videotape from passing around the video drum when play or record is requested. This slice could damage the delicate video heads. None of the function buttons will respond until this operation is over. This splice-avoidance routine commonly occurs when a new or fully rewound cassette is loaded into the VCR. This routine is normal and not a defect.
8. Tape-recognition sensor: Some models have an LED emitter and detector that senses if the tape is located in the correct position before threading can occur. If the tape does not break the light beam between the two sensors, the cassette will be ejected. Notation: This is an indication that the tape has either threaded incorrectly and missed the detector or it is separated. This problem requires using a different cassette, or if it continues with all tapes, repair.
9. Record-lockout switch: This switch checks to see if the cassette has been prevented (protected) from being recorded. It looks to discover if the record prevention tab has been removed. If recording is attempted using a cassette that is missing its safety tab, the VCR will prevent it. Depending on the model, it will either do nothing and wait for you to discover the problem or eject the cassette. If there is a "cassette inside" indicator in the display it might flash to show that it cannot be recorded. The talking Betas will announce: "The safety tab in the cassette is missing" while the icon flashes. Notation: To record over a protected cassette, place a strip of tape over the protection hole. This will defeat the protection feature.
10. Capstan-rotation sensor: If play or record is requested and the capstan cannot turn, the VCR will shut down. To detect and execute this safety feature, the capstan uses a rotation sensor. It informs the main processor that it is successfully turning. Failure to rotate can be caused by a damaged cassette, damaged capstan, or tape wrapped around the spindle. Another culprit might be that the cassette is not going down completely flat inside the tape compartment due to an obstruction. Notation: Capstan monitoring is necessary to prevent the tape from bunching up inside the machine and causing damage. In most cases after a rotation failure, only the power or eject switches will function. The VCR also knows when the VCR is in pause mode and the capstan is not supposed to be turning. If the machine remains in pause for over eight minutes, play or record will resume. If the capstan fails to turn after pause shutdown will occur. (See item 14 below.) If the capstan continues to cause a problem repair is needed.
11. Tape-slack-sensor: During play or record, if the tape becomes too loose in the path, the VCR will shut down. The slack sensor detects if it is not traveling properly and informs the main processor that forward tension has been lost. This can be caused by a damaged cassette, damaged capstan, reel rotation failure, or a broken tape. Notation: Tension monitoring is necessary to prevent the tape from bunching up inside the machine and causing damage. In most cases after a tape slack failure, only the power or eject switches will function. If tape tension cannot be properly maintained repair is needed.
12. Tape-movement sensor: These are rotation sensors that detect if the tape reels are moving correctly as it travels through the VCR. A failure here causes it to shut down, and in most cases, only the power and eject buttons will work. This rotation shutdown is usually caused by a take-up reel that fails to turn properly. The cassette also might not be going down completely flat inside the tape compartment due to an obstruction. Notation: With models that have Step-motion in reverse, the supply reel is also monitored. Continued rotation problems indicates repair is needed.
13. Tape tracking controls: The tracking adjustment is used to achieve tape interchangeability between VCRs. Technically not a sensor but important when playing back tapes that were recorded on another Beta VCR. Turning this control or pressing the tracking buttons will slow and speed up the capstan slightly. This removes unwanted noise from the picture caused by the minor mechanical differences in machines. Tracking has no effect during recording, only playback. Notation: Adjustment is normally not needed when playing back tapes recorded on the same VCR. If a model features single-frame, slow-motion or Step-motion playback, it could also have a separate tracking adjustment for these special modes.
14. Pause time-out circuit: Detects if the VCR has been held in the pause mode for too long (over eight minutes). This is done to prevent damage from heat caused by the spinning video heads rubbing against the tape. A timing program in the main processor tells the VCR to abort pause and return to playback or record. It can also default to the stop mode. Notation: Prolonged pause can cause excessive heat to build up in the heads and on the surface of the tape. This is because they are repeatedly striking in the same area. Excess heat will cause the tape binder to soften and deposit itself on the head surfaces. It then becomes bonded to the video heads, causing picture problems. Cleaning or repair is usually needed if this happens. If the heads will not come clean, then replacement will be needed.
15. Tape-end stop sensors: There are usually two of these sensors, one for each direction. These detect the foil (film) tape leader attached to each end of the tape. When this foil passes by the end sensor (coil device), it causes a change in conductivity in the coil and that triggers a circuit that stops the tape's movement. Once terminated, depending on the model, the tape will be rewound. If the end is reached during timer recording the machine usually stops, then turns off. When the foil passes by the rewind sensor the tape stops. These sensors are located on either side of the tape path near the cassette openings. Notation: Failure can cause the machine to continue to run when it should stop or rewind. If this happens, the tape movement sensor (see 12 above) will step in and shut the machine off. If it occurs during winding it can be very abrupt, and damage to the tape or the machine could result. Repair is usually needed if a tape-end sensor fails.
16. Motor-overload sensor: During rewind and fast-forward, the force required to turn the reel drive motor and pull the tape is monitored by the motor servo processors. If the rotation effort exceeds a certain limited amount, they will stop the motor to prevent it from overheating (see 2 above). Notation: After a shutdown usually only the power and eject buttons will work. Continued failure indicates repair is needed.
17. Tape unthreading sensor: When eject is requested, the tape is threaded back into the cassette, which is then lifted up and out of the tape compartment. The end of unthreading sensor verifies that the tape threading components have successfully parked in their correct locations and the tape is inside the cassette before the loader lifts the cassette up and then out. Notation: Portables Betas will open the cassette receiver when unthreading is completed. If the position is not satisfied, the tape will re-thread, and the VCR will wait for further instructions. Continued failure to unthread and unload requires a repair.
18. End-of-eject switch: Usually the same switch that is used to recognize a cassette is also used to detect if it has been successfully ejected. When this switch opens it tells the CPU that the cassette is resting in the entryway to stop turning the eject motor (ejecting). Notation: Failure here will cause the loader to reverse and send the cassette back into the VCR. Usually an ejection problem requires repair.
19. DEW sensor: It detects when DEW (condensation) has accumulated on the surface of the aluminum video drum. One of the physical traits of aluminum is that it can attract moisture if there is a sudden change in temperature and there is humidity present. If the drum becomes damp, the thin ribbon of the videotape will stick to it and will not move. This can cause tape damage or mechanical failure. A special condensation sensor conducts when it gets wet and alerts a circuit to shut down operation until a certain standard is met. Notation: Some Betas will only indicate that DEW has been detected, and others will alert and then prevent operation until it is gone. The DEW indicator with shutdown feature is most common in portable Betas because they are easily moved from one environment to another. Some Betas have a drum heater to accelerate the drying time. How the DEW function behaves depends on the model. Consult the VCR's description to see if it has the detection sensor and/or heater function. Always give your Beta VCR about an hour to acclimate itself after it has been moved from a warm to cold climate or vice versa. Not all Betas have a DEW sensor; it depends on the model.
20. Reset switch: Pressing this switch restarts the VCR from a total shutdown condition. If it should become unresponsive or fail to program correctly, pressing thus switch erases all circuits and returns the VCR to a neutral or powered-down state. If an event continues to occur that requires a RESET to recover then repair is needed. Notation: very few Betas came with a reset switch. Unplugging the VCR and waiting several seconds will also initiate a reset condition or startup routine.

Memorandum: From the beginning, many safeguards and circuit protectors were hardwired into every Beta VCR. The very first Betas (like the ones with the piano-type keys) didn't have as many as those as the models that came later. As Beta matured, more safety and operation features were added and became standard. To find out about the other ways that Beta VCRs strived to enhance your home video experience, open the "Auto functions" panel here or on its link in the features list. Also refer to the "Features and Benefits" panel that highlights the beauty of the Beta format by clicking here.

If you have a Beta and you feel repair is indicated, click here to go to my form for getting service. It will appear in the browser window.


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