VCRs in the 90's have really changed since the 80's. They are smaller, lighter and have fewer parts. On some, you actually have to hold them down with one hand while you push the front panel buttons with the other. Other wise, you may push it off what ever it is setting on.
The mechanical decks are much lighter. Metal is kind of getting scarce while more emphasis is being placed on plastics. Even though knowledge about plastic and it's reliability are increasing, there is still a lot in the realm of the unknown that can happen.
Other changes took place. For example, you no longer have major problems with the idler. There are still a few spot problems on some brands, but for the most part the idler has become almost trouble free. Trouble with end sensors and reel sensors are also gone.
Nearly everything has video muting, auto tracking and real time counter. Even the low end cheapies since the mid 90's.
The antenna connectors are now part of a package that contains the modulator, tuner, IF board and connection piece. If someone accidently yanks off an antenna fitting, you have to fix it because the cost of this assembly is prohibitively expensive. If it is unable to be fixed, you still have the option to use the VCR without the tuner.
These machines have problems that did not affect the older ones. Many of these newer VCRs have decks that offer limited access. For example, nearly every VCR before 1990 had an access plate on the bottom that got to everthing underneath easily. On newer VCRs, you have to pull the deck to get to the bottom side. With the deck out, it usually can not be powered up. Not much fun. Anytime you have a cassette stuck inside, you have really got your work cut out. Servicing can be tougher for the above reasons.
However, most of these VCRs can be fixed quickly and easily if you know what to do. Once you are armed with this powerful troubleshooting knowledge, you are in the driver's seat for making a lot of repairs. Just take the time to familiarize yourself with the parts in the VCR Mechanical Components section. No other experience is required.
The top 10 problems of the 90's are detailed below. Good luck!
1. DIRTY HEADS - nearly all VCRs made in the 90's have video muting. This causes your TV screen to go to a solid blue color if there is no video coming out. Often, this can be more difficult to troubleshoot than VCRs without this feature. The tough part is that there are other defects which can cause your monitor to go BLUE. Carefully looking at the following symptoms can quickly narrow it down.
Symptoms:
THE CURE - clean the heads. There are several ways this can be done. Believe it or not, the easiest, is to play an ordinary tape in the VCR for an hour. No, you won't be able to see the picture, so do something else to keep yourself occupied while it plays. Over a period of time the tape removes particles from the heads and restores your picture to normal. The scrubbing action of the video head spinning at 1800 RPM is what makes this possible. Surprisingly, this works about 2/3rds the time.
If that does not work, you will have to open it up and physically clean the heads with swabs and cleaning fluid. If done incorrectly, this can ruin the heads, so be sure to read the section on VCR CLEANING before proceeding.
2. INFRARED TRANSMITTER DIODE - A common problem with VCRs of the mid to late 90's, is this part. In the cassette sensing circuitry, this part transmits infrared energy to the tape end sensors. On older VCRs it was the end sensors that was a common failure. But on newer models, it is the Infrared transmitting diode instead.
It's common symptoms are that it spits the cassette out as soon as you insert it. Usually the VCR will load it up all the way but then issue an eject command. Other VCRs may let you see the movie for a while, and then suddenly it goes dead. On Funai, Hitachi, Magnavox, Philips, Symphonic and Sylvania the cassette ejects when you hit the power button after you noticed it went dead.
THE CURE - Replace the Infrared diode.
3. BELTS - newer VCRs for the most part have fewer belts than their older counterparts. Most of them have less than three. There are no more flat belts on the capstan and the tiny counter belts have vanished entirely. Fewer belts does mean fewer problems, however, pesky problems can still occur when the rubber becomes marginal.
Belts can cause a number of symptoms depending on which belt is failing. First inspect for belts that may have broken or popped off. Then closely scrutinize for cracks or glazing. Next, check for elasticity by streching them about 25% and and see if they return to their original size. If in doubt, you may want to replace all of them. They are now inexpensive and easy to replace on most models.
Symptoms:
4. CPU RESET - do you know where the reset button is on your VCR? If you say there is no such thing, we have a surprise for you. No, it's not a red button on the back, but you can still operate it without even openning your VCR. Simply by removing the AC power plug for about 30 seconds and then plugging it back in again. This resets the CPU. Turning the VCR off with the power button won't work; it must be unplugged.
This can solve a number of problems. Any time your VCR appears to be dead or doesn't respond to anything, try resetting it. Any time it behaves weird, like your channel indicator locks up or your clock goes to all 8's, try resetting it. This phenomenon occurs a lot more often than most people think. The primary cause is believed to be static electricity and power surges. You know that feeling you get when you walk across a staticy carpet and touch something like a door knob. It seems like it shocks your finger tip off. This electricity can also rearrange the digits inside your VCRs CPU. Fortunately, resetting fixes most of these problems.
5. CAPSTAN BEARINGS - symptoms:
6. ANTENNA BLOCK - symptom: coax connector falls off. This can happen if someone yanks on the coax cable a little too hard. Also some VCRs are manufactured so cheaply these days that it is possible they can fall off all by themselves over time. Unfortunately, you just can not glue these back on again.
Nearly all VCRs made in the 90's have the modulator incorporated inside the tuner. That means you have one of the tougher jobs on your hands. If you do have a seperate tuner and modulator, go to Antenna Block on VCRs of the 80's.
Even if you do have a good wholesale source on parts, you are still going to pay at least $70 to $80 or more for this part. So in other words, you are going to have to fix the modulator in order to use the VCR the way you do now. If you can not fix it, you can still use your VCR with the direct video jacks instead. Most of the newer cable boxes and TV's have them. If your TV does not have direct video jacks, you can use an external modulator instead.
To fix it, pull the Tuner-Modulator assembly out of the VCR. It is a lot less crowded when this is the only part on your bench. Remove the covers. You will need a soldering iron that is hotter than what you would use for circuit soldering. Using solder wick, unsolder all points on the board that connect to the frame. If the solder wick has a tendency to stick to the frame, you may need a hotter iron. Also unsolder any points that connect to fittings. Remove the board. Install the new fitting, then reassemble in reverse order.
7. FOREIGN OBJECTS CAUGHT IN MECHANISMS - these objects come from two different sources. Those that get in there by accident, like labels comming off cassettes; and things that get in there by small kids, things like toys, rocks, crayons and food. When one kid was asked why he put a sandwich inside the VCR, his answer was he did not want the cat to get it. Top loaders are more prone to strange objects because whatever is on top has a chance of accidently falling in. Usually these objects cause mechanism jams that trip your VCRs shutdown mechanisms. Anything caught in the roller guide slides will not allow the guides to load up correctly, causing a poor jumpy picture with noisy lines in it. With the cover off, a careful examination of the mechanical mechanisms will usually reveal any foreign objects that do not belong inside. Simply removing them is usually all that is necessary to comeplete the repair.
8. CASSETTE CARRIAGES - symptoms:
In binding situations, carriage may have been bent by some heavy object on top of the VCR. Often, it can be bent back easily. In cases of broken parts see if they can be repaired or glued if replacements are not available.
The easiest solution is to replace the entire carriage. It's an easy task on most VCRs. Most retail in the $25 - 35 range. I would not waste much time on trying to salvage one if knew I could buy a new one at these prices. But if it starts getting over $40, you might want to try harder to salvage the defective unit. For further information see Trouble Shooting the Cassette Carriage.
9. MODE SWITCH - the mode switch is a sensor that reports to the CPU. It senses all the positions of the moving mechanism. An average VCR mode switch has three switches in a sealed unit (that is why it's called a switch). As the mechanism moves, the switches open and close at different intervals. The CPU sees this as three channels of pulsed data and can determine what position the mechanism is in from this. If this sounds a little complicated, all you really need to know is what the symptoms are when it fails.
Failure is caused by one or more of the intermal switches not making reliable contact. It affects the travel of the moving mechanism. Usually if the CPU gets bad data during loadup, it will issue an unload command. The tape appears to be loading normally and then mysteriously unloads. It always starts out intermittant, and progressively gets worse. Sometimes, however, the mechanism will load up but stop in the wrong place without unloading. It may play at the wrong speed, the tension arm may not be correctly positioned causing picture distortions or it might just shut off. Repeatedly pressing play may get it to work in early failure stages, but eventually it will fail comepletely.
The key symptom to look for is "incomplete travel of the moving mechanism". A simple test is to locate the master cam gear (usually the largest gear in the VCR) while the failure is still intermittant and see if it stops in the same place everytime. Making reference marks (a magic marker is best) on the gear after pressing play and again after pressing eject makes this easier to see. Now load and unload the tape by pressing play and eject about 20 times (yes, this takes a while). If the gear stops in a different place just once, the mode switch is most likely defective.
10. Capstan Pulley - underneath the Capstan motor is a pulley for the belt that goes to the reel drive mechanism. This pulley cracks and can do many strange things. When it falls off, it is easy to figure out. But before it does, be on the lookout for these symptoms:
The mechanical decks are much lighter. Metal is kind of getting scarce while more emphasis is being placed on plastics. Even though knowledge about plastic and it's reliability are increasing, there is still a lot in the realm of the unknown that can happen.
Other changes took place. For example, you no longer have major problems with the idler. There are still a few spot problems on some brands, but for the most part the idler has become almost trouble free. Trouble with end sensors and reel sensors are also gone.
Nearly everything has video muting, auto tracking and real time counter. Even the low end cheapies since the mid 90's.
The antenna connectors are now part of a package that contains the modulator, tuner, IF board and connection piece. If someone accidently yanks off an antenna fitting, you have to fix it because the cost of this assembly is prohibitively expensive. If it is unable to be fixed, you still have the option to use the VCR without the tuner.
These machines have problems that did not affect the older ones. Many of these newer VCRs have decks that offer limited access. For example, nearly every VCR before 1990 had an access plate on the bottom that got to everthing underneath easily. On newer VCRs, you have to pull the deck to get to the bottom side. With the deck out, it usually can not be powered up. Not much fun. Anytime you have a cassette stuck inside, you have really got your work cut out. Servicing can be tougher for the above reasons.
However, most of these VCRs can be fixed quickly and easily if you know what to do. Once you are armed with this powerful troubleshooting knowledge, you are in the driver's seat for making a lot of repairs. Just take the time to familiarize yourself with the parts in the VCR Mechanical Components section. No other experience is required.
The top 10 problems of the 90's are detailed below. Good luck!
1. DIRTY HEADS - nearly all VCRs made in the 90's have video muting. This causes your TV screen to go to a solid blue color if there is no video coming out. Often, this can be more difficult to troubleshoot than VCRs without this feature. The tough part is that there are other defects which can cause your monitor to go BLUE. Carefully looking at the following symptoms can quickly narrow it down.
Symptoms:
- Sound is OK
- TV screen is solid blue.
- It happened suddenly. It did not start out a little snowy and get progressively worse over a period of months. Everything was fine and suddenly the picture went blue.
- Picture went out when tape got snarled up in the machine.
THE CURE - clean the heads. There are several ways this can be done. Believe it or not, the easiest, is to play an ordinary tape in the VCR for an hour. No, you won't be able to see the picture, so do something else to keep yourself occupied while it plays. Over a period of time the tape removes particles from the heads and restores your picture to normal. The scrubbing action of the video head spinning at 1800 RPM is what makes this possible. Surprisingly, this works about 2/3rds the time.
If that does not work, you will have to open it up and physically clean the heads with swabs and cleaning fluid. If done incorrectly, this can ruin the heads, so be sure to read the section on VCR CLEANING before proceeding.
2. INFRARED TRANSMITTER DIODE - A common problem with VCRs of the mid to late 90's, is this part. In the cassette sensing circuitry, this part transmits infrared energy to the tape end sensors. On older VCRs it was the end sensors that was a common failure. But on newer models, it is the Infrared transmitting diode instead.
It's common symptoms are that it spits the cassette out as soon as you insert it. Usually the VCR will load it up all the way but then issue an eject command. Other VCRs may let you see the movie for a while, and then suddenly it goes dead. On Funai, Hitachi, Magnavox, Philips, Symphonic and Sylvania the cassette ejects when you hit the power button after you noticed it went dead.
THE CURE - Replace the Infrared diode.
3. BELTS - newer VCRs for the most part have fewer belts than their older counterparts. Most of them have less than three. There are no more flat belts on the capstan and the tiny counter belts have vanished entirely. Fewer belts does mean fewer problems, however, pesky problems can still occur when the rubber becomes marginal.
Belts can cause a number of symptoms depending on which belt is failing. First inspect for belts that may have broken or popped off. Then closely scrutinize for cracks or glazing. Next, check for elasticity by streching them about 25% and and see if they return to their original size. If in doubt, you may want to replace all of them. They are now inexpensive and easy to replace on most models.
Symptoms:
- Reel belt - an early sign of reel belt weakness is when a T-120 cassette (6 hours) during rewind shuts off before it rewinds all the way. Cassettes with less tape work normal. This belt causes few other problems.
- Tape load belt - this belt is by far the biggest trouble maker. VCR may load tape around video drum. At that point insufficient traction results in not being able to complete the load cycle. CPU then issues a shutdown command. Sometimes these belts may squeel when slipping.
- Cassette carriage belt - rarely ever fails.
4. CPU RESET - do you know where the reset button is on your VCR? If you say there is no such thing, we have a surprise for you. No, it's not a red button on the back, but you can still operate it without even openning your VCR. Simply by removing the AC power plug for about 30 seconds and then plugging it back in again. This resets the CPU. Turning the VCR off with the power button won't work; it must be unplugged.
This can solve a number of problems. Any time your VCR appears to be dead or doesn't respond to anything, try resetting it. Any time it behaves weird, like your channel indicator locks up or your clock goes to all 8's, try resetting it. This phenomenon occurs a lot more often than most people think. The primary cause is believed to be static electricity and power surges. You know that feeling you get when you walk across a staticy carpet and touch something like a door knob. It seems like it shocks your finger tip off. This electricity can also rearrange the digits inside your VCRs CPU. Fortunately, resetting fixes most of these problems.
5. CAPSTAN BEARINGS - symptoms:
- VCR may be playing fine and then suddenly the tape speed slows and eventually shuts off (noise bars are traveling though the picture vertically when this is occurring). The audio slows and may waver.
- The picture may also suddenly freeze (as if someone pressed the pause button), and then shut off.
- Press play and the VCR will go again, but for a much shorter time and stop again.
- The problem always appears on the SP speed and almost never on the EP speed.
- bearing may emit a squeaking noise
- put a drop of oil on the bearing and run it a few minutes. If a substance that looks like black pepper comes up out of the bearing, you definately have a bad bearing.
6. ANTENNA BLOCK - symptom: coax connector falls off. This can happen if someone yanks on the coax cable a little too hard. Also some VCRs are manufactured so cheaply these days that it is possible they can fall off all by themselves over time. Unfortunately, you just can not glue these back on again.
Nearly all VCRs made in the 90's have the modulator incorporated inside the tuner. That means you have one of the tougher jobs on your hands. If you do have a seperate tuner and modulator, go to Antenna Block on VCRs of the 80's.
Even if you do have a good wholesale source on parts, you are still going to pay at least $70 to $80 or more for this part. So in other words, you are going to have to fix the modulator in order to use the VCR the way you do now. If you can not fix it, you can still use your VCR with the direct video jacks instead. Most of the newer cable boxes and TV's have them. If your TV does not have direct video jacks, you can use an external modulator instead.
To fix it, pull the Tuner-Modulator assembly out of the VCR. It is a lot less crowded when this is the only part on your bench. Remove the covers. You will need a soldering iron that is hotter than what you would use for circuit soldering. Using solder wick, unsolder all points on the board that connect to the frame. If the solder wick has a tendency to stick to the frame, you may need a hotter iron. Also unsolder any points that connect to fittings. Remove the board. Install the new fitting, then reassemble in reverse order.
7. FOREIGN OBJECTS CAUGHT IN MECHANISMS - these objects come from two different sources. Those that get in there by accident, like labels comming off cassettes; and things that get in there by small kids, things like toys, rocks, crayons and food. When one kid was asked why he put a sandwich inside the VCR, his answer was he did not want the cat to get it. Top loaders are more prone to strange objects because whatever is on top has a chance of accidently falling in. Usually these objects cause mechanism jams that trip your VCRs shutdown mechanisms. Anything caught in the roller guide slides will not allow the guides to load up correctly, causing a poor jumpy picture with noisy lines in it. With the cover off, a careful examination of the mechanical mechanisms will usually reveal any foreign objects that do not belong inside. Simply removing them is usually all that is necessary to comeplete the repair.
8. CASSETTE CARRIAGES - symptoms:
- You hear a clicking noise when power is applied or inserting a cassette.
- Cassette tray on carriage is crooked. If you are lucky, maybe a carriage gear just jumped a tooth.
- Cassette does not go all the way down.
- Cassette does not seat firmly on gaging pins after loading.
- You see broken pieces in carriage assembly.
- Cassette binds, or does not go in when trying to insert.
- Cassette binds or gets stuck while loading under power.
- Cassette does not eject all the way.
- Cassette lid does not open. Cassette opener spring may have sprung.
- Cassette motor is defective.
- Someone forcibly removed a cassette that would not eject.
In binding situations, carriage may have been bent by some heavy object on top of the VCR. Often, it can be bent back easily. In cases of broken parts see if they can be repaired or glued if replacements are not available.
The easiest solution is to replace the entire carriage. It's an easy task on most VCRs. Most retail in the $25 - 35 range. I would not waste much time on trying to salvage one if knew I could buy a new one at these prices. But if it starts getting over $40, you might want to try harder to salvage the defective unit. For further information see Trouble Shooting the Cassette Carriage.
9. MODE SWITCH - the mode switch is a sensor that reports to the CPU. It senses all the positions of the moving mechanism. An average VCR mode switch has three switches in a sealed unit (that is why it's called a switch). As the mechanism moves, the switches open and close at different intervals. The CPU sees this as three channels of pulsed data and can determine what position the mechanism is in from this. If this sounds a little complicated, all you really need to know is what the symptoms are when it fails.
Failure is caused by one or more of the intermal switches not making reliable contact. It affects the travel of the moving mechanism. Usually if the CPU gets bad data during loadup, it will issue an unload command. The tape appears to be loading normally and then mysteriously unloads. It always starts out intermittant, and progressively gets worse. Sometimes, however, the mechanism will load up but stop in the wrong place without unloading. It may play at the wrong speed, the tension arm may not be correctly positioned causing picture distortions or it might just shut off. Repeatedly pressing play may get it to work in early failure stages, but eventually it will fail comepletely.
The key symptom to look for is "incomplete travel of the moving mechanism". A simple test is to locate the master cam gear (usually the largest gear in the VCR) while the failure is still intermittant and see if it stops in the same place everytime. Making reference marks (a magic marker is best) on the gear after pressing play and again after pressing eject makes this easier to see. Now load and unload the tape by pressing play and eject about 20 times (yes, this takes a while). If the gear stops in a different place just once, the mode switch is most likely defective.
10. Capstan Pulley - underneath the Capstan motor is a pulley for the belt that goes to the reel drive mechanism. This pulley cracks and can do many strange things. When it falls off, it is easy to figure out. But before it does, be on the lookout for these symptoms:
- Rewind can be intermittent.
- Rewind may not work at all.
- The search mechanism can behave weird. Check the operation of the pause and search keys.
- May eat tape.
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