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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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VCR image only when fast-forwarding (tried cleaning heads)
Hi,
The VCR quit playing tapes (all of them), but the sound still works. When fast forwarding, the picture is crystal clear (except for the normal static bar). When I switch from fast-forward to play, the picture goes to 3/4 static (where I can still make out the picture, which is no longer fast-forwarding), for a half-second (or less), before going to full static, then just blue. I tried cleaning the heads, which had no effect. The VCR is as ESA. Any ideas? A note on head cleaning: Did I do it right? I must have spent an hour on Google trying to find a picture of VCR heads IN a VCR, before giving up. I had some VCR cleaning fluid and chamois cleaning sticks someone left behind long ago. So I just opened it up and guessed. There's a cylinder that has horizontal lines on the top half, with none at the bottom. At two points 180 deg. apart, in the middle of the cylinder, there are small openings. I assume those are the video heads. I moved the cleaning stick back and forth horizontally over these two areas, as I had read about (no pictures...). I tried this three times, checking with a tape in between. No effect. I still only get an image while fast-forwarding. (So I apparently didn't do additional damage...) I checked the manual, and this is supposed to be a 4-head VCR. Are the heads paired up, with two in each of those two small holes? |
#2
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tim:
Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym .. .. .. |
#3
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Try adjusting the tape guide posts, white plastic cylinders on chrome posts,
up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#4
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"nolsar" writes:
Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. DON'T touch the alignment! I'd quicker go with clogged heads if it's a 4 (or more) head VCR. Then, a different set of heads is used for normal play and FF, and for different speeds. Have you tried playing back tapes recorded at both SP and EP speed? --- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/ Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/ +Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm | Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html Note: These links are hopefully temporary until we can sort out the excessive traffic on Repairfaq.org. Important: Anything sent to the email address in the message header above is ignored unless my full name is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#5
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On Tue, 20 Sep 2005 06:14:18 -0400, "nolsar"
wrote: Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. Don't fiddle with those unless you know exactly what you're doing and have the necessary equipment. You'll only make things a lot worse. Are you sure you're actually cleaning the heads, not just polishing the drum? Again, if you don't know what you're doing, don't do anything. A professional clean is cheaper than new heads. |
#6
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Try adjusting the tape guide posts, white plastic cylinders on chrome
posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#7
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"nolsar" writes:
Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. DON'T touch the alignment! I'd quicker go with clogged heads if it's a 4 (or more) head VCR. Then, a different set of heads is used for normal play and FF, and for different speeds. Have you tried playing back tapes recorded at both SP and EP speed? --- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/ Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/ +Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm | Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html Note: These links are hopefully temporary until we can sort out the excessive traffic on Repairfaq.org. Important: Anything sent to the email address in the message header above is ignored unless my full name is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#8
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#9
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nolsar wrote: Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . There doesn't seem to be a way to adjust that. Like the heads, I can't find a picture of "guide posts" with Google. Are you talking about those two pieces that move to push the tape against the cylinder? Those seem to be fixed, and I don't see any other parts that could effect the tapes position on the cylinder. |
#10
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DON'T touch the alignment! I'd quicker go with clogged heads if it's a 4 (or more) head VCR. Then, a different set of heads is used for normal play and FF, and for different speeds. Have you tried playing back tapes recorded at both SP and EP speed? The VCR quit recording 3-4 months ago, and there isn't another VCR around to make a tape to test SP/EP. This VCR was junk right out of the box - see my reply to the first reply in this thread. |
#11
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Are you sure you're actually cleaning the heads, not just polishing the drum? Again, if you don't know what you're doing, don't do anything. A professional clean is cheaper than new heads. I don't know. That's why I included all those details. Are the heads 180 deg apart in the middle of the drum? There are only two "holes" in the drum, and it's supposed to be a 4-head VCR. |
#12
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????? why would anyone tell a non-technical person who is having difficulty
with a simple task of cleaning the heads tell them to adjust the roller guides or alter any other critical alignment???? More than likely the heads are still dirty or clogged.... or have been damaged by improper cleaning or a defective tape? -- Best Regards, Daniel Sofie Electronics Supply & Repair - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "nolsar" wrote in message eenews.net... Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#13
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#14
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Bad advice. Unless one understands the principles of operation quite well,
tweaking alignment on a VCR is almost certainly not going to solve a problem. If the guides are loose, that needs to be fixed, not just adjusted. Likely still a clogged head or a damaged head. Leonard "nolsar" wrote in message ... Try adjusting the tape guide posts, white plastic cylinders on chrome posts, up or down may need tightening with small flat screwdriver or hex tool, sometimes they become loose and the picture will be half missing. wrote in message oups.com... tim: Either the heads are still dirty or clogged..... or the heads are damaged or broken. An improper or haphazard cleaning can easily damage the fragile head chips. A quick examination by a service shop tech can give you the answer.... many times a small shop can give you a fairly inexpensive diagnosis for the price of a cleaning or less.... and if it just needs to be cleaned, it will be done properly and safely by a shop tech.... and of course, expect to be charged for a cleaning.... and then your VCR will work properly. electricitym . . . |
#15
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writes:
When fast forwarding, the picture is crystal clear (except for the normal static bar). When I switch from fast-forward to play, the picture goes to 3/4 static (where I can still make out the picture, which is no longer fast-forwarding), for a half-second (or less), before going to full static, then just blue. The problem you described certainly sounds like dirty heads, and guck that gets into heads can sometimes be difficult to remove, so it's not all that unusual that your first attempt at cleaning didn't do the job. A note on head cleaning: Did I do it right? I must have spent an hour on Google trying to find a picture of VCR heads IN a VCR, before giving up. Try http://images.google.com and search for vcr heads. So I just opened it up and guessed. There's a cylinder that has horizontal lines on the top half, with none at the bottom. At two points 180 deg. apart, in the middle of the cylinder, there are small openings. I assume those are the video heads. Yes, that's where the heads are. As you guessed, many 4-head VCRs have two openings with two heads each. I moved the cleaning stick back and forth horizontally over these two areas, as I had read about (no pictures...). I've personally found the "dry paper" method very effective for removing really stubborn dirt. In the usual version, one presses a dry strip of plain white (copier or laser printer) paper against the drum and applies moderate-to-strong pressure while turning the drum by hand back and forth to bring the heads across the paper horizontally. In the "I don't care if I break this crappy VCR" variation that I use, I press the strip of paper against the drum while the tape is playing and the drum is spinning normally. In using this version, one must pay attention to which way the drum is spinning (because catching the edge of the paper with a head would be bad) and to the pointy bits on top of the drum (which are flying around at 1800 RPM ready to shred an unwary knuckle). A note on head cleaning: Did I do it right? I must have spent an hour on Google trying to find a picture of VCR heads IN a VCR, before giving up. Try: http://images.google.com/ and search for "vcr heads". Also, see the VCR FAQ he http://www.repairfaq.org/sam/vcrfaq.htm which has a whole chapter devoted to video heads including a description of the dry paper method. -- Kevin |
#17
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To get those heads clean put in a good movie get it playing then hold an
ordinary pencil erasor against the gap on the spinning heads somewhere at the back where no tape is in the way . |
#18
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Ken G. wrote: To get those heads clean put in a good movie get it playing then hold an ordinary pencil erasor against the gap on the spinning heads somewhere at the back where no tape is in the way . Hi Ken... You have a real good name, but I'd sure like to disagree with you anyway I suggest that if you do that, you'll instantly destroy both the heads and the 'good movie'. Clean them properly and thoroughly instead. Piece of chamois, little bit of isopropyl alcohol. Clean gently, look at the gap with a good magnifying glass and flashlight. Repeat as necessary. Give it a few minutes to dry before putting a tape in it. Take care. Ken |
#19
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Agree fully. A pencil eraser on the heads, spinning or not, will
usually result in destroyed head chips..... electricitym |
#20
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You are both wrong . I have done this more times than i can remember on
very stuborn dirty heads . You dont force the erasor in there like shoveling dirt .. you set it on there very light and let it rub for a bit and watch the picture come back . Have you ever tried it ?? no .. so you dont know . It does not hurt the movie tape either . Alcohol is useless to clean anything its just like using water .. throw it out and forget it thats why many people dont get vcr heads clean . The little heads on vcrs are only a problem if the rub up &down across the gap instead of with the gap or push to hard and gouge . They will not melt or absorb anything . I have repaired vcr`s sence the beginning of the boat anchor top loads and work on brand new stuff of today and not a drop of alcohol around . |
#21
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It may work, but why use a dry method that is likely to leave little bits of
eraser in the unit when you can use a chamois or other cleaning products that will hold alcohol and leave no residue. Why take the risk? As for alcohol not being an effective cleaner, I have to differ. It is a lot better than water or dry methods. What do you use to clean the ridges of oxide off of the capstan? I have cleaned many hundreds of VCRs, also since the earliest days of the product, and have found denatured alcohol or isopropanol to be very effective. Leonard "Ken G." wrote in message ... You are both wrong . I have done this more times than i can remember on very stuborn dirty heads . You dont force the erasor in there like shoveling dirt .. you set it on there very light and let it rub for a bit and watch the picture come back . Have you ever tried it ?? no .. so you dont know . It does not hurt the movie tape either . Alcohol is useless to clean anything its just like using water .. throw it out and forget it thats why many people dont get vcr heads clean . The little heads on vcrs are only a problem if the rub up &down across the gap instead of with the gap or push to hard and gouge . They will not melt or absorb anything . I have repaired vcr`s sence the beginning of the boat anchor top loads and work on brand new stuff of today and not a drop of alcohol around . |
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