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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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How to Adjust the Tape Path Alignment on Newer VCRs
I found it difficult to find simple information on the internet on how
to adjust the tape path alignment. I read books in the library but they were all about vcrs built in the 80's and early 90's. They were more complicated than today's vcrs. First, before you think about aligning the tape path, do a thorough cleaning of the capstan and rubber pinch roller with isopropyl alcohol and Q-Tips. May have to clean the capstan a number of times as the tape oxide can be hard to get off. May have to let it set for awhile. Also, clean the A/C head, erase head, and any tape guide that has oxide on it. The tape guides usually stay clean. Don't clean the cylinder heads as they are self cleaning. Only clean the cylinder itself if you see oxide build-up but be very careful not to touch the heads. Now, you cleaned your vcr but your getting a noise bar at the top or bottom of the screen still with a known good tape from a known good vcr. It's time to do a tape path alignment. Noise is at the Bottom of the Screen: If the noise is at the bottom of the screen then you need to turn the take-up roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up higher on the screen. Now turn the roller guide in the direction that moves that noise down off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the bottom of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Let the vcr autotrack again and test the other direction with the tracking control. If you see noise at the top of the picture well before the whole screen turns noisy, you need to turn the supply roller guide, see below. Noise is at the Top of the Screen: If the noise is at the top of the screen then you need to turn the supply roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up lower on the screen. Now turn the roller guide in the direction that moves that noise up off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the top of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Slow Motion Tracking - Optional Not necessary, but here's how you do it. When you hit pause or slow motion you should not see any noise in your picture. Play the known good tape and while in slow motion adjust the tracking control to get the cleanest picture. Now, make a test recording with the vcr you have been adjusting in 6hr mode. Hit slow motion, but don't use the tracking control. There should not be any noise in the picture, if there is noise in the picture, carefully mark the position of the whole A/C head assembly with a permanent marker. Slightly loosen the assembly (usually 1 screw to the chassis on newer vcrs) and barely move it, less than 1/10th inch, one direction or the other until the noise moves off the screen; retighten screw. If you move too much, the noise will be gone but the voice will not match the lips (a multiple of 1/30th second off from the picture). If you move too much, simply start over from the original marked position. A/C Head – Azimuth, Tilt, Height, Should not need Adjusting The A/C head itself is usually ok and should not need adjusting. It needs adjusting if you turn off HiFi sound and can barely hear any sound, the tape is getting wrinkled along one edge, or the vcr can not determine the correct playback speed (2hr, 4hr, 6hr). Basically the A/C head should be as vertical as possible in both the X & Y axis. Again, usually it does not need adjusting. Mark screw positions with a permanent marker. Azimuth Azimuth is left and right tilting of the head parallel to the tape path. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). With a known good tape adjust the A/C azimuth screw for loudest possible treble (the screw is usually the farthest screw to the left or right side of the A/C head). It's ok to turn it quickly in and out a half turn or so to help you find the loudest sound. A scene with music is best for making this adjustment. An 1/8 turn can make a difference in the volume so try to find the best spot. Tilt Tilt is forward and backward tilting perpendicular to the tape path. If tilt is incorrect the tape edge will wrinkle. The tape should be as vertical as possible over the take-up roller guide, A/C head, and tape guide next to the capstan. Make sure the tape is not wrinkling especially at the tape guide by the capstan. You may have to fast forward and rewind an area of the tape a few times, then eject the tape and look at the tape edge to see if it is wrinkling. (Basically the A/C head should be straight up and down, not tilting forward or backward.) If necessary, fine tune the tilt screw (tilt screw is usually in front of the head) for best tape movement without wrinkles - half turn should be enough. Height If height is incorrect, the vcr won't be able to determine the correct tape speed. The tape should be in the middle of the A/C heads. To raise or lower the height all three screws have to be turned an equal amount. Too high or too low you will lose motor sync (the vcr can not determine the correct playback speed (2hr, 4hr, 6hr)). Once you have motor sync keep adjusting for loudest audio. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). If you lose track of your screw positions you can as a last resort tighten all 3 screws and then back them all out the same amount, about 2 turns. The head should be vertical again and this will give you a starting point. |
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#2
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How to Adjust the Tape Path Alignment on Newer VCRs
Jim:
Because of my long repair relationship with consumer VCRs since their introduction well over 20 years ago and with Broadcast 2" Quad and Helical VTRs, 1" and 3/4" Helical VTRs in the 60's and 70's I read your posted "procedure" with great interest..... BUT I am a little taken back by the fact that you did NOT mention the requirement for proper test equipment, factory alignment tapes, tension gauges, mechanical alignment jigs or even proper technical procedures. In order to do this kind of alignment task correctly, and to assure good interchange with all other properly aligned VCRs.... and with repeatability......... a genuine Factory Alignment Tape (expensive.... not just any movie tape or tape that is recorded from some another VCR), a wide band oscilloscope to monitor the RF envelope at the video and hi-fi audio head preamp and the A/C head signals, and the proper alignment tools, back tension gauges, deck plate height gauges, mechanical alignment jigs and the correct technical and mechanical procedures to assure proper adjustments. Also, most VCRs with "auto-tracking" have a procedure to disable the auto track circuitry in order to properly center the mechanical adjustments...... furthermore, the "Optional Slow Motion Tracking" adjustment and the A/C head "tilt" and "height" adjustment procedure as described in your post is something that only should be attempted with the proper deck plate alignment gauges and only after the pinch roller, capstan bearings, TU tension and back-tension are verified to be in completely proper order.... the procedures that you described are going to provide haphazard adjustments at best to these precise mechanisms.... they may make the VCR play, but complete and proper interchange and performance that is up to the specifications can not be assured with the "shade tree mechanic" type procedure that is described..... .......and if one is not very careful, the machine can really be screwed up. These kinds of adjustments do not easily change by themselves and should not be twiddled with indiscriminately..... and should only be adjusted after things like tensions, pinch roller, capstan bearings, etc (things that do wear and change) .....are carefully checked first. Almost all of the machines that come into my shop that require a guide and head alignment are those that need key, critical mechanical or electronic parts replaced, or most usually have been tweaked and twiddled with by the novice home do-it-yourselfer. I applaud your do-it-yourself zeal but you might be best advised to obtain a Factory Service Manual or two for your favorite VCRs along with a good Factory Alignment Tape, wide band oscilloscope and the specified alignment jigs, tension gauges, and alignment tools that are indicated in the Service Manual Procedures...... you will be amazed with the precise and repeatability correct alignment job you can do with the proper equipment, tools and procedures. Best of luck to you on your endeavor to get the most out of your VCR...... -- Best Regards, Daniel Sofie Electronics Supply & Repair ------------------------- "Jim" wrote in message om... I found it difficult to find simple information on the internet on how to adjust the tape path alignment. I read books in the library but they were all about vcrs built in the 80's and early 90's. They were more complicated than today's vcrs. First, before you think about aligning the tape path, do a thorough cleaning of the capstan and rubber pinch roller with isopropyl alcohol and Q-Tips. May have to clean the capstan a number of times as the tape oxide can be hard to get off. May have to let it set for awhile. Also, clean the A/C head, erase head, and any tape guide that has oxide on it. The tape guides usually stay clean. Don't clean the cylinder heads as they are self cleaning. Only clean the cylinder itself if you see oxide build-up but be very careful not to touch the heads. Now, you cleaned your vcr but your getting a noise bar at the top or bottom of the screen still with a known good tape from a known good vcr. It's time to do a tape path alignment. Noise is at the Bottom of the Screen: If the noise is at the bottom of the screen then you need to turn the take-up roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up higher on the screen. Now turn the roller guide in the direction that moves that noise down off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the bottom of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Let the vcr autotrack again and test the other direction with the tracking control. If you see noise at the top of the picture well before the whole screen turns noisy, you need to turn the supply roller guide, see below. Noise is at the Top of the Screen: If the noise is at the top of the screen then you need to turn the supply roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up lower on the screen. Now turn the roller guide in the direction that moves that noise up off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the top of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Slow Motion Tracking - Optional Not necessary, but here's how you do it. When you hit pause or slow motion you should not see any noise in your picture. Play the known good tape and while in slow motion adjust the tracking control to get the cleanest picture. Now, make a test recording with the vcr you have been adjusting in 6hr mode. Hit slow motion, but don't use the tracking control. There should not be any noise in the picture, if there is noise in the picture, carefully mark the position of the whole A/C head assembly with a permanent marker. Slightly loosen the assembly (usually 1 screw to the chassis on newer vcrs) and barely move it, less than 1/10th inch, one direction or the other until the noise moves off the screen; retighten screw. If you move too much, the noise will be gone but the voice will not match the lips (a multiple of 1/30th second off from the picture). If you move too much, simply start over from the original marked position. A/C Head - Azimuth, Tilt, Height, Should not need Adjusting The A/C head itself is usually ok and should not need adjusting. It needs adjusting if you turn off HiFi sound and can barely hear any sound, the tape is getting wrinkled along one edge, or the vcr can not determine the correct playback speed (2hr, 4hr, 6hr). Basically the A/C head should be as vertical as possible in both the X & Y axis. Again, usually it does not need adjusting. Mark screw positions with a permanent marker. Azimuth Azimuth is left and right tilting of the head parallel to the tape path. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). With a known good tape adjust the A/C azimuth screw for loudest possible treble (the screw is usually the farthest screw to the left or right side of the A/C head). It's ok to turn it quickly in and out a half turn or so to help you find the loudest sound. A scene with music is best for making this adjustment. An 1/8 turn can make a difference in the volume so try to find the best spot. Tilt Tilt is forward and backward tilting perpendicular to the tape path. If tilt is incorrect the tape edge will wrinkle. The tape should be as vertical as possible over the take-up roller guide, A/C head, and tape guide next to the capstan. Make sure the tape is not wrinkling especially at the tape guide by the capstan. You may have to fast forward and rewind an area of the tape a few times, then eject the tape and look at the tape edge to see if it is wrinkling. (Basically the A/C head should be straight up and down, not tilting forward or backward.) If necessary, fine tune the tilt screw (tilt screw is usually in front of the head) for best tape movement without wrinkles - half turn should be enough. Height If height is incorrect, the vcr won't be able to determine the correct tape speed. The tape should be in the middle of the A/C heads. To raise or lower the height all three screws have to be turned an equal amount. Too high or too low you will lose motor sync (the vcr can not determine the correct playback speed (2hr, 4hr, 6hr)). Once you have motor sync keep adjusting for loudest audio. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). If you lose track of your screw positions you can as a last resort tighten all 3 screws and then back them all out the same amount, about 2 turns. The head should be vertical again and this will give you a starting point. |
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#3
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How to Adjust the Tape Path Alignment on Newer VCRs
Daniel Sofie,
I know where you're coming from and because vcrs are so cheap nobody will pay to have one fixed anymore. I know this technique works perfect for me in all 3 of my vcrs. I record and play tapes and they all play perfect no matter which vcr is used for the recording. The things you mentioned seem to date back when vcrs cost hundreds of dollars, not $69 for a 4-Head HiFi. This can help people save $69 if they wish to take the time to make the adjustment. What do they have to lose? |
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#4
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How to Adjust the Tape Path Alignment on Newer VCRs
Come now Dan, you know that the equipment to do it right costs thousands.
If the guy can eyeball it and get acceptable results, why not tinker? It's not worth the time for an experienced tech to do a complete alignment anyway on any but the most expensive of consumer VCRs these days. If he screws it up he can replace it for what it would cost to have it aligned. Everything you said is correct, but in today's market simply your advice is simply unrealistic. A single test tape costs more than a VCR these days. The manufacturers don't even fix them at warranty rates, for the most part. Leonard "Sofie" wrote in message ... Jim: Because of my long repair relationship with consumer VCRs since their introduction well over 20 years ago and with Broadcast 2" Quad and Helical VTRs, 1" and 3/4" Helical VTRs in the 60's and 70's I read your posted "procedure" with great interest..... BUT I am a little taken back by the fact that you did NOT mention the requirement for proper test equipment, factory alignment tapes, tension gauges, mechanical alignment jigs or even proper technical procedures. In order to do this kind of alignment task correctly, and to assure good interchange with all other properly aligned VCRs.... and with repeatability......... a genuine Factory Alignment Tape (expensive.... not just any movie tape or tape that is recorded from some another VCR), a wide band oscilloscope to monitor the RF envelope at the video and hi-fi audio head preamp and the A/C head signals, and the proper alignment tools, back tension gauges, deck plate height gauges, mechanical alignment jigs and the correct technical and mechanical procedures to assure proper adjustments. Also, most VCRs with "auto-tracking" have a procedure to disable the auto track circuitry in order to properly center the mechanical adjustments...... furthermore, the "Optional Slow Motion Tracking" adjustment and the A/C head "tilt" and "height" adjustment procedure as described in your post is something that only should be attempted with the proper deck plate alignment gauges and only after the pinch roller, capstan bearings, TU tension and back-tension are verified to be in completely proper order.... the procedures that you described are going to provide haphazard adjustments at best to these precise mechanisms.... they may make the VCR play, but complete and proper interchange and performance that is up to the specifications can not be assured with the "shade tree mechanic" type procedure that is described..... ......and if one is not very careful, the machine can really be screwed up. These kinds of adjustments do not easily change by themselves and should not be twiddled with indiscriminately..... and should only be adjusted after things like tensions, pinch roller, capstan bearings, etc (things that do wear and change) .....are carefully checked first. Almost all of the machines that come into my shop that require a guide and head alignment are those that need key, critical mechanical or electronic parts replaced, or most usually have been tweaked and twiddled with by the novice home do-it-yourselfer. I applaud your do-it-yourself zeal but you might be best advised to obtain a Factory Service Manual or two for your favorite VCRs along with a good Factory Alignment Tape, wide band oscilloscope and the specified alignment jigs, tension gauges, and alignment tools that are indicated in the Service Manual Procedures...... you will be amazed with the precise and repeatability correct alignment job you can do with the proper equipment, tools and procedures. Best of luck to you on your endeavor to get the most out of your VCR...... -- Best Regards, Daniel Sofie Electronics Supply & Repair ------------------------- "Jim" wrote in message om... I found it difficult to find simple information on the internet on how to adjust the tape path alignment. I read books in the library but they were all about vcrs built in the 80's and early 90's. They were more complicated than today's vcrs. First, before you think about aligning the tape path, do a thorough cleaning of the capstan and rubber pinch roller with isopropyl alcohol and Q-Tips. May have to clean the capstan a number of times as the tape oxide can be hard to get off. May have to let it set for awhile. Also, clean the A/C head, erase head, and any tape guide that has oxide on it. The tape guides usually stay clean. Don't clean the cylinder heads as they are self cleaning. Only clean the cylinder itself if you see oxide build-up but be very careful not to touch the heads. Now, you cleaned your vcr but your getting a noise bar at the top or bottom of the screen still with a known good tape from a known good vcr. It's time to do a tape path alignment. Noise is at the Bottom of the Screen: If the noise is at the bottom of the screen then you need to turn the take-up roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up higher on the screen. Now turn the roller guide in the direction that moves that noise down off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the bottom of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Let the vcr autotrack again and test the other direction with the tracking control. If you see noise at the top of the picture well before the whole screen turns noisy, you need to turn the supply roller guide, see below. Noise is at the Top of the Screen: If the noise is at the top of the screen then you need to turn the supply roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up lower on the screen. Now turn the roller guide in the direction that moves that noise up off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the top of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Slow Motion Tracking - Optional Not necessary, but here's how you do it. When you hit pause or slow motion you should not see any noise in your picture. Play the known good tape and while in slow motion adjust the tracking control to get the cleanest picture. Now, make a test recording with the vcr you have been adjusting in 6hr mode. Hit slow motion, but don't use the tracking control. There should not be any noise in the picture, if there is noise in the picture, carefully mark the position of the whole A/C head assembly with a permanent marker. Slightly loosen the assembly (usually 1 screw to the chassis on newer vcrs) and barely move it, less than 1/10th inch, one direction or the other until the noise moves off the screen; retighten screw. If you move too much, the noise will be gone but the voice will not match the lips (a multiple of 1/30th second off from the picture). If you move too much, simply start over from the original marked position. A/C Head - Azimuth, Tilt, Height, Should not need Adjusting The A/C head itself is usually ok and should not need adjusting. It needs adjusting if you turn off HiFi sound and can barely hear any sound, the tape is getting wrinkled along one edge, or the vcr can not determine the correct playback speed (2hr, 4hr, 6hr). Basically the A/C head should be as vertical as possible in both the X & Y axis. Again, usually it does not need adjusting. Mark screw positions with a permanent marker. Azimuth Azimuth is left and right tilting of the head parallel to the tape path. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). With a known good tape adjust the A/C azimuth screw for loudest possible treble (the screw is usually the farthest screw to the left or right side of the A/C head). It's ok to turn it quickly in and out a half turn or so to help you find the loudest sound. A scene with music is best for making this adjustment. An 1/8 turn can make a difference in the volume so try to find the best spot. Tilt Tilt is forward and backward tilting perpendicular to the tape path. If tilt is incorrect the tape edge will wrinkle. The tape should be as vertical as possible over the take-up roller guide, A/C head, and tape guide next to the capstan. Make sure the tape is not wrinkling especially at the tape guide by the capstan. You may have to fast forward and rewind an area of the tape a few times, then eject the tape and look at the tape edge to see if it is wrinkling. (Basically the A/C head should be straight up and down, not tilting forward or backward.) If necessary, fine tune the tilt screw (tilt screw is usually in front of the head) for best tape movement without wrinkles - half turn should be enough. Height If height is incorrect, the vcr won't be able to determine the correct tape speed. The tape should be in the middle of the A/C heads. To raise or lower the height all three screws have to be turned an equal amount. Too high or too low you will lose motor sync (the vcr can not determine the correct playback speed (2hr, 4hr, 6hr)). Once you have motor sync keep adjusting for loudest audio. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). If you lose track of your screw positions you can as a last resort tighten all 3 screws and then back them all out the same amount, about 2 turns. The head should be vertical again and this will give you a starting point. |
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#5
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How to Adjust the Tape Path Alignment on Newer VCRs
Alcohol is old news & not a good cleaner if you want someting cleaned
right . In todays age their are better things . |
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#6
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How to Adjust the Tape Path Alignment on Newer VCRs
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#7
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How to Adjust the Tape Path Alignment on Newer VCRs
Leonard Caillouet:
So then the guy will be making archival tapes on machines with suspect interchange alignment and years from now he will not be able to play and track the tapes properly on another machine....... and because he tinkered with A/C head tilt to compensate for a worn pinch roller or bent guides he will have permanently edge-damaged his tapes and not the audio will be bad or the tape won't track at all because of the crinkled edges. ..... and whenever he rents or borrows a tape, he will return it with possible wrinkle and edge damage....... TERRIFIC. -- Best Regards, Daniel Sofie Electronics Supply & Repair --------------------------- "Leonard Caillouet" wrote in message news:rWZ2c.11712$fD2.9300@lakeread02... Come now Dan, you know that the equipment to do it right costs thousands. If the guy can eyeball it and get acceptable results, why not tinker? It's not worth the time for an experienced tech to do a complete alignment anyway on any but the most expensive of consumer VCRs these days. If he screws it up he can replace it for what it would cost to have it aligned. Everything you said is correct, but in today's market simply your advice is simply unrealistic. A single test tape costs more than a VCR these days. The manufacturers don't even fix them at warranty rates, for the most part. Leonard "Sofie" wrote in message ... Jim: Because of my long repair relationship with consumer VCRs since their introduction well over 20 years ago and with Broadcast 2" Quad and Helical VTRs, 1" and 3/4" Helical VTRs in the 60's and 70's I read your posted "procedure" with great interest..... BUT I am a little taken back by the fact that you did NOT mention the requirement for proper test equipment, factory alignment tapes, tension gauges, mechanical alignment jigs or even proper technical procedures. In order to do this kind of alignment task correctly, and to assure good interchange with all other properly aligned VCRs.... and with repeatability......... a genuine Factory Alignment Tape (expensive.... not just any movie tape or tape that is recorded from some another VCR), a wide band oscilloscope to monitor the RF envelope at the video and hi-fi audio head preamp and the A/C head signals, and the proper alignment tools, back tension gauges, deck plate height gauges, mechanical alignment jigs and the correct technical and mechanical procedures to assure proper adjustments. Also, most VCRs with "auto-tracking" have a procedure to disable the auto track circuitry in order to properly center the mechanical adjustments...... furthermore, the "Optional Slow Motion Tracking" adjustment and the A/C head "tilt" and "height" adjustment procedure as described in your post is something that only should be attempted with the proper deck plate alignment gauges and only after the pinch roller, capstan bearings, TU tension and back-tension are verified to be in completely proper order.... the procedures that you described are going to provide haphazard adjustments at best to these precise mechanisms.... they may make the VCR play, but complete and proper interchange and performance that is up to the specifications can not be assured with the "shade tree mechanic" type procedure that is described..... ......and if one is not very careful, the machine can really be screwed up. These kinds of adjustments do not easily change by themselves and should not be twiddled with indiscriminately..... and should only be adjusted after things like tensions, pinch roller, capstan bearings, etc (things that do wear and change) .....are carefully checked first. Almost all of the machines that come into my shop that require a guide and head alignment are those that need key, critical mechanical or electronic parts replaced, or most usually have been tweaked and twiddled with by the novice home do-it-yourselfer. I applaud your do-it-yourself zeal but you might be best advised to obtain a Factory Service Manual or two for your favorite VCRs along with a good Factory Alignment Tape, wide band oscilloscope and the specified alignment jigs, tension gauges, and alignment tools that are indicated in the Service Manual Procedures...... you will be amazed with the precise and repeatability correct alignment job you can do with the proper equipment, tools and procedures. Best of luck to you on your endeavor to get the most out of your VCR...... -- Best Regards, Daniel Sofie Electronics Supply & Repair ------------------------- "Jim" wrote in message om... I found it difficult to find simple information on the internet on how to adjust the tape path alignment. I read books in the library but they were all about vcrs built in the 80's and early 90's. They were more complicated than today's vcrs. First, before you think about aligning the tape path, do a thorough cleaning of the capstan and rubber pinch roller with isopropyl alcohol and Q-Tips. May have to clean the capstan a number of times as the tape oxide can be hard to get off. May have to let it set for awhile. Also, clean the A/C head, erase head, and any tape guide that has oxide on it. The tape guides usually stay clean. Don't clean the cylinder heads as they are self cleaning. Only clean the cylinder itself if you see oxide build-up but be very careful not to touch the heads. Now, you cleaned your vcr but your getting a noise bar at the top or bottom of the screen still with a known good tape from a known good vcr. It's time to do a tape path alignment. Noise is at the Bottom of the Screen: If the noise is at the bottom of the screen then you need to turn the take-up roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up higher on the screen. Now turn the roller guide in the direction that moves that noise down off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the bottom of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Let the vcr autotrack again and test the other direction with the tracking control. If you see noise at the top of the picture well before the whole screen turns noisy, you need to turn the supply roller guide, see below. Noise is at the Top of the Screen: If the noise is at the top of the screen then you need to turn the supply roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up lower on the screen. Now turn the roller guide in the direction that moves that noise up off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the top of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Slow Motion Tracking - Optional Not necessary, but here's how you do it. When you hit pause or slow motion you should not see any noise in your picture. Play the known good tape and while in slow motion adjust the tracking control to get the cleanest picture. Now, make a test recording with the vcr you have been adjusting in 6hr mode. Hit slow motion, but don't use the tracking control. There should not be any noise in the picture, if there is noise in the picture, carefully mark the position of the whole A/C head assembly with a permanent marker. Slightly loosen the assembly (usually 1 screw to the chassis on newer vcrs) and barely move it, less than 1/10th inch, one direction or the other until the noise moves off the screen; retighten screw. If you move too much, the noise will be gone but the voice will not match the lips (a multiple of 1/30th second off from the picture). If you move too much, simply start over from the original marked position. A/C Head - Azimuth, Tilt, Height, Should not need Adjusting The A/C head itself is usually ok and should not need adjusting. It needs adjusting if you turn off HiFi sound and can barely hear any sound, the tape is getting wrinkled along one edge, or the vcr can not determine the correct playback speed (2hr, 4hr, 6hr). Basically the A/C head should be as vertical as possible in both the X & Y axis. Again, usually it does not need adjusting. Mark screw positions with a permanent marker. Azimuth Azimuth is left and right tilting of the head parallel to the tape path. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). With a known good tape adjust the A/C azimuth screw for loudest possible treble (the screw is usually the farthest screw to the left or right side of the A/C head). It's ok to turn it quickly in and out a half turn or so to help you find the loudest sound. A scene with music is best for making this adjustment. An 1/8 turn can make a difference in the volume so try to find the best spot. Tilt Tilt is forward and backward tilting perpendicular to the tape path. If tilt is incorrect the tape edge will wrinkle. The tape should be as vertical as possible over the take-up roller guide, A/C head, and tape guide next to the capstan. Make sure the tape is not wrinkling especially at the tape guide by the capstan. You may have to fast forward and rewind an area of the tape a few times, then eject the tape and look at the tape edge to see if it is wrinkling. (Basically the A/C head should be straight up and down, not tilting forward or backward.) If necessary, fine tune the tilt screw (tilt screw is usually in front of the head) for best tape movement without wrinkles - half turn should be enough. Height If height is incorrect, the vcr won't be able to determine the correct tape speed. The tape should be in the middle of the A/C heads. To raise or lower the height all three screws have to be turned an equal amount. Too high or too low you will lose motor sync (the vcr can not determine the correct playback speed (2hr, 4hr, 6hr)). Once you have motor sync keep adjusting for loudest audio. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). If you lose track of your screw positions you can as a last resort tighten all 3 screws and then back them all out the same amount, about 2 turns. The head should be vertical again and this will give you a starting point. |
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#8
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How to Adjust the Tape Path Alignment on Newer VCRs
Ken G:
Alcohol is perfectly good as long as you stay away from the "cheap 70% (30% water) Isopropyl Alcohol you get at the drug stores..... I have regularly used either 91% (available at most drug stores) or even 99% if you can find it. . It has always worked great. Some of the "better things" in "today's age" can attack plastic and bonding agents..... and Freon, while safe on plastics and glue is good, it is not as nearly as good as universal solvent as alcohol to clean up sticky water based stuff like soda pop, coffee, food debris, spit, snot, etc...... all of these kinds of things end up on tapes and in the VCR. -- Best Regards, Daniel Sofie Electronics Supply & Repair -------------------------- "Ken G." wrote in message ... Alcohol is old news & not a good cleaner if you want someting cleaned right . In todays age their are better things . |
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#9
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How to Adjust the Tape Path Alignment on Newer VCRs
Like I said Dan, you are correct, just unrealistic in your suggestion. It
is a fact of the market. Leonard "Sofie" wrote in message ... Leonard Caillouet: So then the guy will be making archival tapes on machines with suspect interchange alignment and years from now he will not be able to play and track the tapes properly on another machine....... and because he tinkered with A/C head tilt to compensate for a worn pinch roller or bent guides he will have permanently edge-damaged his tapes and not the audio will be bad or the tape won't track at all because of the crinkled edges. ..... and whenever he rents or borrows a tape, he will return it with possible wrinkle and edge damage....... TERRIFIC. -- Best Regards, Daniel Sofie Electronics Supply & Repair --------------------------- "Leonard Caillouet" wrote in message news:rWZ2c.11712$fD2.9300@lakeread02... Come now Dan, you know that the equipment to do it right costs thousands. If the guy can eyeball it and get acceptable results, why not tinker? It's not worth the time for an experienced tech to do a complete alignment anyway on any but the most expensive of consumer VCRs these days. If he screws it up he can replace it for what it would cost to have it aligned. Everything you said is correct, but in today's market simply your advice is simply unrealistic. A single test tape costs more than a VCR these days. The manufacturers don't even fix them at warranty rates, for the most part. Leonard "Sofie" wrote in message ... Jim: Because of my long repair relationship with consumer VCRs since their introduction well over 20 years ago and with Broadcast 2" Quad and Helical VTRs, 1" and 3/4" Helical VTRs in the 60's and 70's I read your posted "procedure" with great interest..... BUT I am a little taken back by the fact that you did NOT mention the requirement for proper test equipment, factory alignment tapes, tension gauges, mechanical alignment jigs or even proper technical procedures. In order to do this kind of alignment task correctly, and to assure good interchange with all other properly aligned VCRs.... and with repeatability......... a genuine Factory Alignment Tape (expensive.... not just any movie tape or tape that is recorded from some another VCR), a wide band oscilloscope to monitor the RF envelope at the video and hi-fi audio head preamp and the A/C head signals, and the proper alignment tools, back tension gauges, deck plate height gauges, mechanical alignment jigs and the correct technical and mechanical procedures to assure proper adjustments. Also, most VCRs with "auto-tracking" have a procedure to disable the auto track circuitry in order to properly center the mechanical adjustments...... furthermore, the "Optional Slow Motion Tracking" adjustment and the A/C head "tilt" and "height" adjustment procedure as described in your post is something that only should be attempted with the proper deck plate alignment gauges and only after the pinch roller, capstan bearings, TU tension and back-tension are verified to be in completely proper order.... the procedures that you described are going to provide haphazard adjustments at best to these precise mechanisms.... they may make the VCR play, but complete and proper interchange and performance that is up to the specifications can not be assured with the "shade tree mechanic" type procedure that is described..... ......and if one is not very careful, the machine can really be screwed up. These kinds of adjustments do not easily change by themselves and should not be twiddled with indiscriminately..... and should only be adjusted after things like tensions, pinch roller, capstan bearings, etc (things that do wear and change) .....are carefully checked first. Almost all of the machines that come into my shop that require a guide and head alignment are those that need key, critical mechanical or electronic parts replaced, or most usually have been tweaked and twiddled with by the novice home do-it-yourselfer. I applaud your do-it-yourself zeal but you might be best advised to obtain a Factory Service Manual or two for your favorite VCRs along with a good Factory Alignment Tape, wide band oscilloscope and the specified alignment jigs, tension gauges, and alignment tools that are indicated in the Service Manual Procedures...... you will be amazed with the precise and repeatability correct alignment job you can do with the proper equipment, tools and procedures. Best of luck to you on your endeavor to get the most out of your VCR...... -- Best Regards, Daniel Sofie Electronics Supply & Repair ------------------------- "Jim" wrote in message om... I found it difficult to find simple information on the internet on how to adjust the tape path alignment. I read books in the library but they were all about vcrs built in the 80's and early 90's. They were more complicated than today's vcrs. First, before you think about aligning the tape path, do a thorough cleaning of the capstan and rubber pinch roller with isopropyl alcohol and Q-Tips. May have to clean the capstan a number of times as the tape oxide can be hard to get off. May have to let it set for awhile. Also, clean the A/C head, erase head, and any tape guide that has oxide on it. The tape guides usually stay clean. Don't clean the cylinder heads as they are self cleaning. Only clean the cylinder itself if you see oxide build-up but be very careful not to touch the heads. Now, you cleaned your vcr but your getting a noise bar at the top or bottom of the screen still with a known good tape from a known good vcr. It's time to do a tape path alignment. Noise is at the Bottom of the Screen: If the noise is at the bottom of the screen then you need to turn the take-up roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up higher on the screen. Now turn the roller guide in the direction that moves that noise down off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the bottom of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Let the vcr autotrack again and test the other direction with the tracking control. If you see noise at the top of the picture well before the whole screen turns noisy, you need to turn the supply roller guide, see below. Noise is at the Top of the Screen: If the noise is at the top of the screen then you need to turn the supply roller guide, usually less than 1/4 of a turn. Use the tracking control on your remote to make the noise show up lower on the screen. Now turn the roller guide in the direction that moves that noise up off the screen. (Try not to push down to hard when you turn the roller guide. You can notch out an old screwdriver or use 2 screwdrivers to turn it.) Adjust tracking again until you see the noise again. You know when you have adjusted enough when the whole screen starts to get noisy almost the same time you start seeing the noise at the top of the screen. Now let the vcr auto track (pwr off/on) and use the tracking control again to check. It should take about 3 or 4 seconds of holding down the tracking control before you see the whole screen become noisy. Slow Motion Tracking - Optional Not necessary, but here's how you do it. When you hit pause or slow motion you should not see any noise in your picture. Play the known good tape and while in slow motion adjust the tracking control to get the cleanest picture. Now, make a test recording with the vcr you have been adjusting in 6hr mode. Hit slow motion, but don't use the tracking control. There should not be any noise in the picture, if there is noise in the picture, carefully mark the position of the whole A/C head assembly with a permanent marker. Slightly loosen the assembly (usually 1 screw to the chassis on newer vcrs) and barely move it, less than 1/10th inch, one direction or the other until the noise moves off the screen; retighten screw. If you move too much, the noise will be gone but the voice will not match the lips (a multiple of 1/30th second off from the picture). If you move too much, simply start over from the original marked position. A/C Head - Azimuth, Tilt, Height, Should not need Adjusting The A/C head itself is usually ok and should not need adjusting. It needs adjusting if you turn off HiFi sound and can barely hear any sound, the tape is getting wrinkled along one edge, or the vcr can not determine the correct playback speed (2hr, 4hr, 6hr). Basically the A/C head should be as vertical as possible in both the X & Y axis. Again, usually it does not need adjusting. Mark screw positions with a permanent marker. Azimuth Azimuth is left and right tilting of the head parallel to the tape path. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). With a known good tape adjust the A/C azimuth screw for loudest possible treble (the screw is usually the farthest screw to the left or right side of the A/C head). It's ok to turn it quickly in and out a half turn or so to help you find the loudest sound. A scene with music is best for making this adjustment. An 1/8 turn can make a difference in the volume so try to find the best spot. Tilt Tilt is forward and backward tilting perpendicular to the tape path. If tilt is incorrect the tape edge will wrinkle. The tape should be as vertical as possible over the take-up roller guide, A/C head, and tape guide next to the capstan. Make sure the tape is not wrinkling especially at the tape guide by the capstan. You may have to fast forward and rewind an area of the tape a few times, then eject the tape and look at the tape edge to see if it is wrinkling. (Basically the A/C head should be straight up and down, not tilting forward or backward.) If necessary, fine tune the tilt screw (tilt screw is usually in front of the head) for best tape movement without wrinkles - half turn should be enough. Height If height is incorrect, the vcr won't be able to determine the correct tape speed. The tape should be in the middle of the A/C heads. To raise or lower the height all three screws have to be turned an equal amount. Too high or too low you will lose motor sync (the vcr can not determine the correct playback speed (2hr, 4hr, 6hr)). Once you have motor sync keep adjusting for loudest audio. (HiFi machines - use the SAP/HiFi on the remote and turn the HiFi off). If you lose track of your screw positions you can as a last resort tighten all 3 screws and then back them all out the same amount, about 2 turns. The head should be vertical again and this will give you a starting point. |
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#10
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How to Adjust the Tape Path Alignment on Newer VCRs
"Ken G." wrote in message ... Alcohol is old news & not a good cleaner if you want someting cleaned right . In todays age their are better things . Like what? Leonard |
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#11
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How to Adjust the Tape Path Alignment on Newer VCRs
Leonard G. Caillouet:
Hopefully, for the customer's (and I have quite a few regulars who want to do this) who still want their top of the line VCR repaired and are willing to pay the price, particularly for the terrific machines from the early 90's ..... Sony, JVC, Mitz, etc....... that there are still shops with experienced techs that they can go to that do the repair and alignment correctly with all the proper procedures and not with "seat of the pants" methods that may produce inferior performance, tape damage and poor interchange. For the home do-it-yourselfer, I suppose it is fine, after all it is their machine and hopefully it's their tapes...... but for a real shop that has a reputation to hold up.... they better do it right....... and no, Leonard, it DOES NOT cost "thousands of dollars" for the right equipment to do it right. I do understand that for the cheapie $39 VCRs.... almost any repair doesn't make sense..... I have seen customers throw them out just because the heads became clogged after playing a dirty and damaged tape..... just to end up putting that same tape into their new replacement VCR and have it happen all over again. They won't even pay for a $20 cleaning at a shop...... not much need for that "customer." Would you take your modern car to a mechanic who does not have the proper, mandatory and necessary computer interfaced diagnostic equipment to make software adjustments for the fuel injection, engine timing, etc? -- Best Regards, Daniel Sofie Electronics Supply & Repair - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "Leonard G. Caillouet" wrote in message Come now Dan, you know that the equipment to do it right costs thousands. If the guy can eyeball it and get acceptable results, why not tinker Like I said Dan, you are correct, just unrealistic in your suggestion. It is a fact of the market. Leonard |
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#12
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How to Adjust the Tape Path Alignment on Newer VCRs
In article ,
Sofie wrote: I applaud your do-it-yourself zeal but you might be best advised to obtain a Factory Service Manual or two for your favorite VCRs along with a good Factory Alignment Tape, wide band oscilloscope and the specified alignment jigs, tension gauges, and alignment tools that are indicated in the Service Manual Procedures...... In doing this, you will spend enough money to put the video in a chaffeur driven hire vehicle, have it taken to a dump at the other end of the country, pay for disposal, tip the driver, and replace the video twice over. Anyone considering buying all the correct equipment as advised above would need to be servicing videos on a professional basis, for money, in volume. So for the DIYers, following the posted instructions and "bodging on through" with a bit of common sense is the only alternative. Or taking it to a service place for them to do it, which may not be financially worthwhile. Mike. -- --------------------------------------+------------------------------------ Mike Brown: mjb[at]pootle.demon.co.uk | http://www.pootle.demon.co.uk/ |
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#13
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How to Adjust the Tape Path Alignment on Newer VCRs
I use 99% Isopropyl Alcohol I buy from Longs Drug Store. Works pretty
good. I also tried the 70% Isopropyl Alcohol once but it takes a lot more scrubbing to clean the oxide off. |
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#14
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How to Adjust the Tape Path Alignment on Newer VCRs
I've posted this befo gasoline antifreeze, like the brand name 'Heet' are
usually 99.?% pure alcohol. I picked up a couple of bottles on closeout for a quarter apiece a few years ago, and I'm still using them up. Check the label for contents, some brands may be different. (I used the 'Heet' brand name by default--only one I could think of at the moment--I'm not sure of the contents of that particular brand; but it's probably the same.) jak Jim wrote: I use 99% Isopropyl Alcohol I buy from Longs Drug Store. Works pretty good. I also tried the 70% Isopropyl Alcohol once but it takes a lot more scrubbing to clean the oxide off. |
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#15
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How to Adjust the Tape Path Alignment on Newer VCRs
"jakdedert" wrote in message = . .. I've posted this befo gasoline antifreeze, like the brand name = 'Heet' are usually 99.?% pure alcohol. I picked up a couple of bottles on = closeout for a quarter apiece a few years ago, and I'm still using them up. I hope you realize that 'Heet' is methanol not isopropyl alcohol. Much = to reactive for VCR cleaning. Dave |
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#16
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How to Adjust the Tape Path Alignment on Newer VCRs
Thanks for the heads up. The label on the bottles I bought are long gone,
but it seems I remembered otherwise...not 'Heet' brand...still, I suspect you are right. OTOH, I've not had any trouble with the stuff melting anything. jak "David" wrote in message om... "jakdedert" wrote in message . .. I've posted this befo gasoline antifreeze, like the brand name 'Heet' are usually 99.?% pure alcohol. I picked up a couple of bottles on closeout for a quarter apiece a few years ago, and I'm still using them up. I hope you realize that 'Heet' is methanol not isopropyl alcohol. Much to reactive for VCR cleaning. Dave |
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#17
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How to Adjust the Tape Path Alignment on Newer VCRs
I would like to remind people that they should mark the original
position of the roller guides with a permanent marker so they know where they started from. |
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#18
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How to Adjust the Tape Path Alignment on Newer VCRs
I would like to remind people that they should mark the original
position of the roller guides with a permanent marker so they know where they started from. |
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#19
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How to Adjust the Tape Path Alignment on Newer VCRs
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#20
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How to Adjust the Tape Path Alignment on Newer VCRs
twilson wrote:
Will this procedure help correct the tracking problems I'm having with VHS tapes of family videos created in the early 80's? I have tried playing the video tape on a couple of 4 head hi-fi vcr's and the tracking at the bottom of the screen is horrible. I want to play the video on a vcr, and then send the output to my PC for capture and subsequent writing to DVD. Just a guess, but were these videos recorded at the EP (SLP) speed? |
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#21
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How to Adjust the Tape Path Alignment on Newer VCRs
ric wrote in :
twilson wrote: Will this procedure help correct the tracking problems I'm having with VHS tapes of family videos created in the early 80's? I have tried playing the video tape on a couple of 4 head hi-fi vcr's and the tracking at the bottom of the screen is horrible. I want to play the video on a vcr, and then send the output to my PC for capture and subsequent writing to DVD. Just a guess, but were these videos recorded at the EP (SLP) speed? Exactly. LP, and SLP on a RCA Selectavision. |
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#22
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How to Adjust the Tape Path Alignment on Newer VCRs
twilson wrote:
Just a guess, but were these videos recorded at the EP (SLP) speed? Exactly. LP, and SLP on a RCA Selectavision. And do the VCRs that you are trying to play these tapes back on use 19 micron heads? Probably. Try an older VCR that doesn't have 19 micron heads. |
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#23
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How to Adjust the Tape Path Alignment on Newer VCRs
ric wrote in :
twilson wrote: Just a guess, but were these videos recorded at the EP (SLP) speed? Exactly. LP, and SLP on a RCA Selectavision. And do the VCRs that you are trying to play these tapes back on use 19 micron heads? Probably. Try an older VCR that doesn't have 19 micron heads. Yes. One of them is a Sharp with 19u head. Not so sure about the other one, but it's also a newer 4 head hi-fi. Will try out your suggestion of using an older player. Thanks. |
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#24
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How to Adjust the Tape Path Alignment on Newer VCRs
Sounds like the vcr tape path was off on the vcr you used in the early
80's to record your family videos. What you could try: Mark the position of the take-up roller guide and then turn it clockwise to see if you can move the noise down below the screen. Do your PC capture and then move the guide exactly back to its original position. Jim Will this procedure help correct the tracking problems I'm having with VHS tapes of family videos created in the early 80's? I have tried playing the video tape on a couple of 4 head hi-fi vcr's and the tracking at the bottom of the screen is horrible. I want to play the video on a vcr, and then send the output to my PC for capture and subsequent writing to DVD. |
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#25
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How to Adjust the Tape Path Alignment on Newer VCRs
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