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.