TRV900 Cleaning and Maintenance

The Cause of Tape Crinkles.
Jerry's Camera Cleaning for Crinkle Prevention
John's Illustrated Guide to Camera Cleaning
Steven's Head and Tape Path Cleaning, Step by Step
Solvents for Tape Residue, an Opinion
C-Mech Service Manual p.23: head cleaning
One Cause of Audio Dropouts (tape transport).
Another audio problem (internal mics).
How to replace TRV900 internal mics.
Tape Crease: a note
Sony Head Cleaning Tech Notes
VCR care suggestions at
Other Reports of tape crinkles
Help, I spilled soda on my camera
TRV900 internals photos of complete TRV900 disassembly (Dutch site) [NEW!]

On Nov. 2 1999, I had my TRV900 running unattended> recording a dance performance. It ran longer than expected so the tape ran to the very end. I was using a fresh Pansonic 60-minute tape just out of the wrapper, which had not been retensioned prior to use. After recording on the tape, I rewound to the beginning. I think the tape damage happened as I started to rewind: I was taking the camera off the tripod and may have been rotating the camera as it was rewinding.

The tape played back normally, but in the last five minutes of the tape playback (from about 0:55:00 to 1:02:00) there were quite a few audio dropouts and a few video dropouts. These were the first audio drops I've ever heard, having recorded over 50 tapes in my camera. When I started to rewind the tape after viewing, I immediately heard a "crinkle" sound, then almost immediately the tape stopped and the display flashed C:31:23. Error 23 means "S reel emergency during normal rotation" according to p.5-59 of the TRV900 service manual. I tried the eject switch at this point and got a flashing C:32:20. According to the error list this means "T reel side tape slacking when unloading" which apparently equates to "tape jammed". All controls were now inoperable.

Turning now to the regular user's manual, I observed on p. 130 that the C:31:xx and C:32:xx error codes indicate a "user servicible condition". It says to remove the tape and try again. No controls worked including tape eject, so that didn't help, but the second suggestion was to remove the battery and power cord, and plug it in again. I did this twice and the second time, the head made a clicking sound, the error message went away, and the eject switch became functional, allowing me to eject the tape. A few inches of tape were hanging out of the MiniDV cassette at this time. I rewound the tape onto the cassette with a pencil eraser against the takeup reel hub, but the tape was badly wrinkled as you can see in the images above.

Meanwhile, the camera appeared to function, with no error message, but again the eject button refused to open the (now empty) cassette compartment. I carried the camera around the next day using it as a digital still camera (that part worked fine), and that afternoon the eject switch suddenly worked- I have no explanation for this.

In order to rewind the above-pictured cassette, I had to manually wind the tape past the crinkled portion by releasing the reel lock (near the center of underside of cassette, between the two reel hubs) with a small stylus and simultaneously winding with the pencil eraser.

After this event, my camera was apparently working normally. However, it subsequently crinkled another tape during rewind, this time in the middle of the tape. After that I stopped using normal rewind and instead used 2x speed reverse play. Then, the camera crinkled a third tape in 2x reverse play mode. At this point I brought it into the Sony service center in San Jose (along with a printout of this web page). Sony advises that camcorder repairs normally take 10 working days, but around holidays (eg. Christmas) they are more busy and it takes longer. If you are looking for Sony service information, this site may help.

They fixed mine in six working days (I dropped off and picked up myself). The receipt states "CONSTANT IRREGULAR MOTION, MECHANICAL ADJUSTMENT, CLEANED AND/OR LUBRICATED". No parts were replaced. There was an attached note stating that tapes recorded previously may be unable to play back now, as the camera may have been previously functioning incorrectly. A handwritten addendum states: "Please do not play back the damaged or eaten tapes." So far the repaired camera plays back its prior (undamaged) tapes without problems, both in SP and LP mode. When doing FF or rewind, it seems to me the tape drive motion has a somehow smoother or cleaner sound to it, and by comparison it was wheezy or a touch rattley before. But I did not notice this specifically before the repair so it may be my imagination. The repair comes with a new 90-day warranty so I'll excercise the camera during that time.

After the camera came back from Sony I noticed that the steadyshot function was no longer working. I brought it in again and they fixed this for free, since it was under the 90-day post-service warranty, in 8 working days including return shipment. The receipt states "CONSTANT DATA INPUT/OUTPUT, RESOLDER, CLEANED AND/OR LUBRICATED".

NOTE:One user has reported apparently fixing the tape crinkle problem himself merely by cleaning the camera.

How do I avoid this happening with my camera? may be wondering.

According to my sources, tape crinkle damage can be caused by two things: 1) accumulation of "gunk" on the capstan shaft, and 2) insufficient takeup reel torque allowing the tape to slip off one of the tape guides (TG7, next to the capstan and pinch roller). I suspect the more common problem is (1) buildup of gunk, and you can clean the camera yourself if you wish (note: head-cleaning tapes clean the head, not the capstan, so they do not help with this particular problem). Gunk buildup was apparently the problem with my camera.

If the T-reel tension is too low (less than 0.69 mN*m), it can cause tape crinkle as the tape slides off the bottom edge of tape guide TG7 during rewind. Takeup reel torque is fixed at a Sony service center by replacing the T reel table. Sony originally specified 0.44-0.93 mN*m torque on the T-reel of the C-mechanism drive unit (TRV9, TRV900) but after the tape crinkle issue surfaced, this spec was changed to 0.69-1.32 mN*m (that happened on or before January 2000, I believe). This means that late-model TRV900 cameras should be less likely to suffer from crinkle cause (2). BUT crinkle cause (1), gunk build-up, can still occur. Sorry, I don't know the serial number beyond which this was implemented, and I personally suspect that all TRV900s are equally potential victims of cause (1) which is likely the dominant failure mechanism. It may be that residue build-up is increased by mixing tape brands, or by specific brands, or heat, humidity or other factors but I have no evidence of this myself. Just keep an eye on your capstan shaft and clean it, if necessary (see instructions for this).

Tape crinkle and tape jam happens most frequently, but not exclusively, at the last 5 minutes of a reel. The problem can occur just when rewinding, not necessarily when playing or recording. It is possible that it is not reported more frequently than it is (a handful of reports out of my 150+ respondent TRV900 reliability survey) because many users do not record to the absolute end of a tape.

I have reproduced a page of the service manual if you are interested. You can see a few other users' reports of this problem here.

Subject: Sony TRV900 and damaged tapes
Date: Tue, 9 Nov 1999 23:55:28 -0800 (PST)
Cc: beale (John P. Beale)

Dear Sony Customer Service:
Recently my Sony DCR-TRV900 MiniDV camera, which has sucessfully recorded
55 tapes over the past year, damaged one of my MiniDV tapes by wrinkling
the tape (apparently while rewinding, while near the end of the
cassette). This caused at first severe dropouts, and then an actual tape
jam. I describe the particulars of this incident on my TRV900 web page
including a picture of the tape in question. In my case this was a
Panasonic tape, although others have reported the same problem using Sony
tapes and other brands. Several people have had this problem and you can
see some of their experiences here:
In my case, I was able to clear the tape jam by removing power from the
unit and connecting it again (twice); however the tape and the video and
sound on it remain damaged. My experience and that of others has caused
understandable concern on the active TRV900 mailing list run by Chris
Current and prospective TRV900 owners are questioning the reliability of
the unit, the causes of this particular failure mode (causing wrinkled
tape) and what steps if any Sony plans to take in light of this
As you may know, I run a web page with information and a FAQ concerning the
TRV900. The page receives visits from several hundred people a day. I have
already posted my experience with the tape wrinkle issue on my page, and I
would like to also post your response to the problem. I invite you to
address these concerns either by replying to me, and/or addressing the
TRV900/PD100 mailing list directly.
Thank you for your time.
John Beale
TRV900 FAQ maintainer:

Date: Thu, 11 Nov 1999 15:28:29 -0500
To: "John P. Beale"
Subject: Re: Sony TRV900 and damaged tapes (KMM145168C0KM)
From: Custserv
Reply-To: Custserv
X-Mailer: Kana Customer Messaging System 3.0
Message-Id: <>

Dear Sony Customer:
Thank you for contacting Sony.
This situation would best be addressed by troubleshooting through the
Digital Imaging Hotline. They will be able to discuss this with you and
ask the pertinent questions necessary to discern the problem.
Please contact our Digital Imaging Hotline and speak with a
representative for assistance.
Digital Imaging Hotline
(phone) 1-888-449-7669
(hours - EST) M-F 8:30 a.m. - 6:00 p.m.
Sat 9:00 a.m. - 6:00 p.m.
I hope this information is helpful, and thank you for your interest in
Sony products.
Best regards,
Sony Internet Department

Phone call: 888-449-7669
Thursday Nov. 11 1999

I called the number in the message above, and got a response after about 5
minutes on hold. The tech indicated that this tape crinkle problem can be
caused by any contamination on the tape: "Any sticky substance, any water,
any foreign material can be picked up by the pinch roller and cause the
tape to wrap around it. But if you run a dry cleaning tape through the
mechanism that may clear up the problem. If it still occurs you may need to
bring the camera in for service." Ironically enough I had just run a dry
cleaning tape through the camera immediately before the tape crinkle
incident, and the crinkled tape was brand-new fresh out of the
wrapper. Anyway, that was all the information I could get out of him.

Subject: Tape crinkle reduces TRV900 to a lunch box full of pieces.
Date: Fri, 12 Nov 1999 16:55:23 +1100
From: Simon Plint
I dropped my TRV900 off at my local authorised repair centre yesterday. I
nearly wrote you then to tell of my concern about not being allowed to talk
to the service person and feeling completely at the mercy of the centre.
I had handed over my camera with a handful of pages, printed from this list,
thinking that they would go unread but, to the centre's credit, with a week
and a half of work already in progress the service person read the pages
last night, took my camera apart today then rang me to come in and have a
look for myself. I jumped in the car and raced in to the centre and was
presented with the reel table from the camera, one of the many other bits
lying in a plastic work bin nearby that, had they all been joined together,
would have been my TRV900.
He explained that the problem was that various rollers and a capstan all had
scum on them. I asked wether this would be enough to de-rail a tape and he
said that it was possible. He added that it would be more likely if the scum
were heated because then it actually sticks to the tape. I could see the
scum he was talking about and we then went on to discuss many things.
FWIW, I do recall that at the time of my incident I had the camera in a
vertical position on my copy stand with lights close by.
He explained to me firstly that the camera required cleaning, not repair,
and that SONY would not cover this under warranty. I asked wether he thought
this was an acceptable amount of scum deposit, considering that I had only
put about 10 60 minute tapes through the camera. He said he would be
concerned but then went on to explain how the scum gets there.
He explained that during manufacture the tape is actually cut from bigger
sheets of tape and, like when a knife cuts through a cake, small deposits of
the bonding agent are left on the edges of the tape. This is what creates
the scum.
I asked him about pre tensioning tapes and he explained that this was not
necessary with the TRV900 because of the magnetic clutch on the reel table
which allows for varying tensions.
Another interesting thing that he pointed out, that I did not realise
although I am sure it has been mentioned on this list, is that the TRV900
fully loads the tape around all the heads and stuff when ever the drive is
operated. This is so that the tape is ready to go as soon as you finish
rewinding and hit play. I thought that the tape would come away from the
heads during rewind (as opposed to Play/Rewind).
He suggested I give SONY tapes a try but admitted that he had used heaps of
the Panasonic tapes in various DV camera's, he has quite a few that he hires
out. He also supplies Panasonic tapes to all the students at the University
here and he has had no complaints.
As I have probably mentioned before, I have a TRV900 that I use at work and
I took that with me. The service guy had a look and said he could see a
similar build up on it's capstan as well.
I'm not saying that scum build up is the cause of the "tape crinkle" problem
but it is another view point and I think it's early days yet and a bit soon
to be talking of letters to SONY and class actions.
Let's let the dust (scum, sorry) settle and see what other service people
have to say.
Simon Plint
Thanks for The Memories.
thanks hunterlink net au

Subject: [TRV900] Tape crinkle: A solution?
Date: Mon, 15 Nov 1999 09:45:30 -0600
From: Jerry Anderson
I had shot about 30 tapes on my TRV-900 without suffering the tape crinkle
problem until last night. I had 6 tapes that I had recorded to the end and
never rewound. The first two tapes crinkled and jammed badly as soon as I
hit rewind. After the first wave of panic subsided I decided to try to
think out the physics of the problem and see if there was something I could do.
Here are the items that I thought could be behind the problem:
1. The take-up reel motor is obviously pretty powerful so it can still move
the tape when the take-up reel is full, therefore there must be a lot of
torque applied to the take-up when it is empty as is the case when you have
recorded to the end of a tape.
2. If anything is preventing the tape from moving easily during a rewind
operation something has to give, and of course it will be the tape.
3. One thing that could keep the tape from moving easily is if the tape on
the supply reel is sticking to the inside of the tape housing. This often
happens with audio cassettes that haven't been played for a long time and
have been exposed to temperature and humidity changes. The tight tolerances
inside a mini-DV tape could cause this to happen even after slight changes
in temperature or humidity. My tapes had not be subjected to any unusual
conditions but uneven winding of the tape could also be the cause.
4. Another thing that could keep the tape from moving easily from the
supply reel is if the movement lock is still engaged inside the housing.
Mini-DV tapes, like VHS tapes, have an internal lock that keeps the tapes
from moving when the cassette is not loaded inside a tape drive. A small
sliding lever inside a hole in the bottom center of the cassette frees the
lock from the tape reels. If this lock is sticking, even a little, this
could be the problem. I have had this happen with cheap VHS tapes. Possibly
the tape load mechanism in the TRV-900 doesn't fully disengage the movement
5. The last possibility I could imagine concerns the record head. When a
tape is loaded into the camera it is wrapped around the record head.
Normally when the tape is moving this head is spinning at high speed which
causes a thin film of air to move between the tape and the record head
lubricating movement of the tape. I believe that the tape stays wrapped
around the head during rewind and playback. When you first hit rewind it
sounds to me that the record head is not spinning so the lubricating layer
of air would not be present and the friction of trying to drag the tape
across the record head as it is pulled by the take-up reel would cause the
tape to crinkle. It is possible that the tape head is supposed to start
spinning during rewind but doesn't get going fast enough for a film of air
to always develop before the take-up reel motor has done it's damage.
I decided the following the following procedures might be a solution:
1. I gently wrapped both flat sides of the cassette down on a flat hard
surface to help be sure the tape was wound flat and not sticking to the
sides of the cassette.
2. I wiggled the visible tape hubs to verify that they were moving loosely.
3. Using a pen point I slid the tape movement lock lever to be sure it was
moving freely.
4. I loaded the tape and first pressed 'play'. This was to ensure that the
record head was spinning. As soon as the tape started moving I pressed and
held down on the rewind button. Now the tape was fast scanning backwards. I
went backwards this way for about five minutes of tape time.
5. I then hit stop and very quickly hit rewind. Now that I knew the tape
was moving freely and the record head was spinning there should be nothing
to keep the tape from rewinding smoothly. Also by having rewound five
minutes of the tape the torque on the take-up reel would not be as great.
What happened?
I was able to rewind the other four tapes without incident. In fact I then
used the same procedure to rewind the first two tapes that had initially
jammed. They also rewound now without further incident.
This is not an exhaustive experiment but give it a try and give your
feedback. I suspect one or more of the things I have listed here is the
root of the problem.
Addition comments on the quality control of the TRV-900.
1. On my camera the button to seek to the end of the recorded segment on
the tape only works about 1 time in 10.
2. My microphones are very unbalanced. I almost exclusively use external
microphones so it doesn't effect me very much.
3. As part of reviewing the above 6 tapes I heard sound drop-outs near the
end of one of the tapes. They did not seem to repeat in exactly the same
places when I replayed the tape. I had heard other people report this
problem but never observed it myself.
4. I have had a lot of problems working around the very noisy microphone
pre-amps when plugging in external mics.
I am shocked that a reputable company like Sony would release a camera that
has so much promise but that seems to have so many flaws.

> Subject: Tape crease
> Date: Wed, 10 May 2000 00:44:29 -0400
> From: Douglas Morse
> Is tape crease (which I seem to have) different from the infamous tape
> crinkle and can anyone suggest remedies?
I believe it is. I believe it is a manufacturing fault which is more common
than people think. I have experienced it on 5 tapes now (out of 100) and it
seems to occur in the last 5 minutes of the tape. Brands or tape quality do
not seem to be a factor.
I showed one of my creased tapes to the techo at my SONY authorised repair
centre and he agreed that it was different from tape crinkle and offered to
replace the tape. I don't think that there is much you can do about. I think
that it is one of those things that SONY would address on an individual
basis but overall they could claim that they were within spec.
Another side to this issue, and this is pure speculation on my part, is that
I believe that it is possible for tape crease to cause a tape to become
I would go as far as to say that you can not rely on the last 5 minutes of
any tape. If you are filming an event and you get down to the last 5 minutes
of the tape then put a new one in if possible. A creased tape can ruin
footage and it can not be good for the heads.
Whilst we are on the subject of creases and crinkles I used the search
function last night while the camera was in Rec. mode and it made the same
sound it made just before I had my first tape crinkle. I think what was
actually happening was that the tape was bunching up at the capstan. I think
that when using the search buttons it is possible for the tape to be fed to
the capstan faster than it can handle it. Again this is my speculation but
perhaps others might care to comment.
I am not sure wether the tape was damaged before but when playing it back I
saw waves across the screen. I ejected the tape straight away and found
scrub marks on the surface of the tape.
So there seems to be 3 forms of tape problems that can occur, tape crinkle,
tape crease and tape scrub.

Subject: SONY statement on tape crinkle problem of TRV900
Date: Wed, 07 Jun 2000 15:43:34
From: Peter Plewka (dk6hq at freenet de)
After reading the newsgroup I wrote a letter to SONY in Cologne Germany
and asked them what they intend to do about the tape crinkle problem.
Today they called me and here is what they say:
Tape crinkling can occur with any kind of device that uses tape. Also
other cameras like Panasonic and JVC have this problem if the user does
not clean the tape path from time to time. Cleaning the tape path is very
important to keep the tape running where it should. It also is noted in
the service manual.
SONY suggested to use Isopropyl Alcohol (90%) and a cotton stick first and
after waiting a minute to have a run with the SONY cleaning tape.
I asked for a time interval for this procedure and the answer was: Always
then when residue is to be seen on the capstands and guides of the tape
path. As the user can easily take a look at the tape path when removing or
loading a tape, a view into the tape path takes place in very short
intervals. Thus tape crinkle can not happen.
If it should in spite of all these precautions SONY invited me to send the
camera to the SONY Service Center in Germany. The gentleman at SONY
admitted, that there is a slight possibility of misadjustment on the tape
path. He said that they had some cameras with this problem. During the
warranty time (1 year by SONY and another year by the shop I got it from
in Germany) they will fix this within ten days absolutely free. If the
problem does not occur during the time of warranty SONY invited me to send
the camera in anyway if I fear that something might be wrong. They will
check the TRV900 completely and send it back to me within ten days. If
there would be anything to adjust or repair they would do so at no cost
for me because of the existing warranty. If everything is ok with the
camera they would not do anything to it and send it back to me with a test
report. This also is a free service of SONY.
So I will go on to enjoy my TRV900 and before the warranty time is over I
will take the camera to the SONY service center and have it checked.
Peter Plewka

By the way, not everyone has experienced the tape crinkle problem. An inquiry on the TRV900 mailing list generated about 20 replies from people who had never had the problem, including these:

Had the machine since 1/99...500+ hours...cleaned professionally at 430 crinkle (knock on wood)...mostly Sony tape, a few JVC...
-Al Swett, 29 June 2000

[...] I have a crinkle-free TRV900 that I purchased
in late September 1998. I have shot about 80 tapes, and frequently use the
camera for playback while out on shooting trips. I have had no problems
whatsoever with this camera, which replaced a somewhat trouble-prone Canon
A1 Digital that endured the same usage pattern, albeit for eight years.
I have used primarily Sony, JVC, and Fuji tapes, purchased in USA (and about
10 Sony and JVC tapes purchased in China) and have never had a problem,
although I am going to heed the advice of this list and perform a camera
cleaning soon. I never have cleaned the camera before. I have noticed very
occasional dropouts, but usually only near the very beginning of a tape. I
do shoot my tapes to the end, but I frequently rewind and play back mid-tape
before reaching tape-end.
I have not posted to this list before, but I was an early user of the John
Beale TRV-900 Site of Sites, which has been and continues to be tremendously
useful to me.
- A Happy TRV-900 consumer, Greg (6/29/00)

Subject: Timecode resets, matching cleaning tape brands
From: Dave Millman
Date: Oct. 19 2001
The resetting timecode problem drove me crazy for months. Sometimes it
would reset while the camera was on standby in between shots! I also
started getting the cleaning cassette message every hour or less of usage.
I religiously use just Panasonic tapes. I discovered to my dismay that my
cleaning cassette was Sony brand. You can read on John Beale's site about
the problem of mixing tape brands.
Anyhow, I switched to a Panasonic cleaning cassette. I have not had an
instance of time code reset or cleaning cassette message since then. I
speculate that mixing Panasonic tapes with Sony cleaning cassette was
causing a problem.
I also wet clean my tape path according to the instructions on the Beale
site, but do not touch the video heads.
Dave Millman

Subject: Soda spilled on camera
Date: Oct. 25 2001

My kids spilled soda all over my Sony camcorder. I sent it away to be fixed but they sent it back saying there was nothing that can be done. I don't trust techs that much. Is there a way I can fix it myself?

Most soft drinks contain phosphoric acid. If it gets inside the camera, the acid can etch copper circuit traces away, as well as serve as an electrolyte which permits electrochemical corrosion if the camcorder had a battery installed at the time. Also, the sugars/syrup can gunk up any moving parts: mechanical switches as well as the tape transport, to say nothing of the lens surfaces and zoom motor.

If the camera has been declared a total loss, I suppose there's no harm in trying, anyway. You might get lucky. What you can try is to rinse off the camera in absolutely clean water (preferably distilled water) to remove all sugary residues and ionic contamination from all affected surfaces, circuit boards, and components. Note, if the internal (electret) microphones get wet they may be permanently damaged, and have to be replaced. After cleaning let everything dry THOROUGHLY before attempting to apply power. It may well not be possible to really clean it without disassembling it pretty completely- this can be done by anyone with a screwdriver, but you must take a great deal of care to keep track of all the tiny screws, small parts, and where each one goes and the order in which they are assembled. The internal circuit boards are connected with very fine, fragile ribbon cables; re-connecting them probably requires tweezers and some manual dexterity (and patience).

If you are very lucky the camera might work, but you'll still need to clean the heads, if those got dirty or wet at any stage during the initial spill or subsequent cleaning efforts. If the soda spill or cleaning has removed various lubricating oil films on the motor transport, this lubrication ought to be replaced, but I don't know how this might be accomplished. You must be careful not to let any oil or grease contaminate the tape path or heads. I have not heard from anyone who has tried this kind of cleaning. Good luck.

The Cause of Tape Crinkles.
Jerry's Camera Cleaning for Crinkle Prevention
John's Illustrated Guide to Camera Cleaning
Steven's Head and Tape Path Cleaning, Step by Step
C-Mech Service Manual p.23: head cleaning
The Cause of Audio Dropouts.
Tape Crease: a note
Sony Head Cleaning Tech Notes

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