Learn to Fix Vintage VCRs
If you have been a ham radio operator for any length of time, it’s probable that most of your extended family and neighbors know it. Quite frequently you will become known as the electronics genius. With that title comes the probability that someone will ask you to something.
That something often turns out to be a VCR. Now what do you do? If you’ll follow the steps I outline below, the process will be a lot less painful, and often successful.
Here’s what I usually do:
l) Take the cover off. With the unit unplugged, take the bottom and top covers off. Than shake the unit. Quite often something will fall out. It might be a small part, but usually it is a foreign object.
I have found that children can all kinds of stuff through that little door. That includes pencils, toothbrushes, noodles, small toys, coins, etc. Make sure it all gets removed. If a tape is stuck inside, locate the small motor which operates the carriage, and try moving the gear or pulley with your thumb. This will often back the tape out. Sometimes you can connect a fresh nine volt battery to the motor pins, and get it to back out too. lf a tape was stuck inside, the cause is likely a small loading belt that is slipping. Replace it, along with other things I will point out here. But don’t stop yet, read on!
2) Plug the unit in, and see if it will accept a tape. If not, the cause could be a bent carriage, cracked gear, or a bad end sensor that thinks a tape is already in the VCR. Also, don’t forget that belt in step one. When the tape has been accepted, try to fast forward, then stop and rewind. A failure to do either or both of these is usually due to a worn out idler tire.
In many machines, this is quite visible from the top, on some from the bottom.
The newer VCR’s have plastic gears, driven by a belt. A worn out tire, or stretched belt will cause this problem. If you need to remove the carriage to get at the idler tire, it usually comes out after loosening four colored screws which anchor it to the frame. Do this only after power is off. The idler tires come off in different ways, and a service manual really helps if you're not familiar with that model. Also, during fast forward and rewind, check to see that the tape counter is moving. If not, this could indicate a stretched belt here too. When replacing belts and tires, it’s a good idea to get everything all at once.
(The common complaint is that the VCR was “eating tapes.”)
3) The next step is to clean the heads. Eject the tape, tum power off, and locate some rubbing alcohol and a good lintless cloth. Chamois skin is often used instead of cloth, but it is more expensive. Moisten the cloth with the alcohol, and holding the head drum still, rub sideways, back and forth only, using the tip of your index finger to press the cloth into the grooves. The heads are quite tiny, and can pick up a lot of dirt. Slowly tum the drum, to make sure you get all the heads clean. Do this at least three times, using a clean spot on the cloth and slowly rotating the drum. Never rub up and down, you might snap the head off.
If it is snapped, or broken, the edge will be quite noticeable on your finger tip. It may even snag the cloth. Drum replacement is the only answer then. Dirty heads usually cause a snowy picture, but on some models they can cause a blue screen. Once the heads are clean, also clean all the guide posts, the full track erase head, and the audio control head similarly. It’s also a good idea to clean the pinch roller, and the capstan shaft too.
4) Insert a tape and play it back. Check playback on all speeds. This can be accomplished if you use a good machine to record a few minutes at SP, then LP, and finally EP. Keep this as a test tape. I change channels every time I change speeds, so I know when the speed is supposed to change. Also, listen to the sound during playback. If it changes by speeding up, or slowing down, accompanied by pictures moving too fast, or slow, you may have a servo loop problem. Did you change all the belts and tires? These can often simulate a problem such as this. Don’t get fooled.
5) After the machine has checked out OK on playback of the test tape, you’ll want to take a blank tape and check record. Once again, do it on all speeds. A minute or so for each is fine. Then play it back. If it plays back normally, we’re almost done, Now, tune to an unused channel and erase what you just recorded. That means disconnect the antenna input, and record noise. Then play it back. There should be no trace of the previous recording. If there is, your erase head is clean. A non-working erase head can also simulate a servo problem.
Of course there are other problems that you may come across. I can’t list them all here, but I’ll give you a few more tips. On older machines, a small lamp was used to activate the end sensors. If that lamp burns open, the machine won’t work. An older machine which shows small white specks on recording and playback may have worn out heads, especially if it was used a lot. Newer machines have many gears in them.
Forcing a tape into it may strip or crack the gears, or cause them to jump timing. A service manual would then be necessary.
Small white streaks can usually be adjusted out with the tracking control. If it doesn’t help, the tape guideposts may have slipped to the wrong height. Look for tape edges curling as a clue to this problem. There are lots more, and I don’t know all of them, but hopefully this will give you some ideas. However, if you are new to this, and don’t know what you’re doing, ask someone who does. Good Luck.
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