Hi, I haven't worked on VCRs for years, but I have a recent interest in 8mm
and Hi8 equipment lately, since the gear is so compact, and some of it
operates away from an AC power soure (DC powered) for remote use.
I still have enough test equipment and safe habits to get by with.

I spotted a used SONY EV C3 8mm VCR (approx 20 years old) at a recent
hamfest, and since it was only $5, I thought I'd get it to see if it was
going to be worthwhile to repair (the nice seller did at least inform me
that it did not work).
While this unit isn't commercial grade, it was cheap enough for curiousity's
sake anyway.

I've done some homework to look up SONY 8mm faults in the archives, and
believe the leaky smt electrolytics in the head amp (all 11 of 'em) repair
tip is definitely accurate for a deck of this vintage with the problem of
playing slow.
The other transport functions operate normally, except Eject. I haven't
tried recording yet, because there isn't much use in it's present condition.

Anyway, the interior of the unit seemed exceptionally clean, and testing
with a pre-recorded tape displayed poor video and audio (appears like very
bad tracking).. unsteady, slow and jittery.

From earlier experience with SONY 8mm gear, I was familiar with loose guide
posts and the resulting poor performance which has always looked as
described, but not necessarily playing slow.
The adjustable guide posts are loose enough to turn with fingertips, so
that's part of the playback problem.

The Unload/Eject problem has me confused (not a difficult situation anymore)
as the tape unloading operation is jerky, and the guide post blocks run back
'n forth while trying to accomplish unloading.
Some times, they stop in the middle and the power can be shut off, then
turned back on to retry Eject.
This might work in one try or may take 3 tries, but then the cassette ejects
quickly when the guide post blocks have reached the fully unloaded position.
There appears to be adequate lubrication on the underside of the mode gear
and associated parts, as I added just a very slight amount for surfaces of
the moving parts.

I don't understand the jerky, back 'n forth motion of the guide posts..
stopping and moving would seem normal, but running forward and reverse has
me baffled.
Would anyone care to enlighten me as to why this might be happening?

I haven't removed the mode switch for examination, but I did drip a couple
of drops of DeoxIT (not flooded) into the switch before running the
mechanism thru numerous cyles, with no change.

There appear to be only 2 very small/tiny cogged belts in this mechanism
(somewhere noted to be the U mechanism that's also used in commercial
units).

Thanks for any insight.

--
Cheers,
WB
...................

Hi David,

It's not as if this machine is very valuable (although it was originally
about $800, not a $50 VHS), but like you, I'd prefer to have it working
instead of laying in a landfill.

I received this response from David F regarding the VCR problems:

Hi WB,

For some reason, my news server didn't post my response to your question.
Basically, replacing the caps in the head amp will fix all the picture,
tracking, speed problems.

As far as the loading mechanism goes, remove a wire from the loading motor
and power it with a small amount of voltage from your power supply. When you
notice it doing something out of the ordinary, immediately remove the power
and investigate what might be causing it to jam. Perhaps a worn tooth on a
gear?

Good luck.

--
David Farber
David Farber's Service Center
L.A., CA




"Wild_Bill" wrote in message
...
--
Cheers,
WB
..................

I don't want to be unduly pessimistic, but Sony's 8mm transports are, to put
it kindly, delicate. I had the transport in a HandyCam and home VCR fail for
no obvious reason, with parts bending or breaking. The VCR is currently
non-functional, with erratic loading.

Narrow tape formats require small transport components, which are difficult
to make "robust".

I know what you mean.. I have a SONY 8mm camcorder with a short round
section of pin (approx 1/8" long) that separated from something in the tape
transport (which may be the only thing wrong with it), but I'm lacking the
enthusiasm to start disassembling the mechanism to see if it's original
location can be found.

The tape transport in the EV C3 VCR is described as being the same one used
in commercial 8mm decks, so it's not quite as flimsy as the consumer version
seen in camcorders, just not a lot better in design, though.

--
Cheers,
WB
..............


"William Sommerwerck" wrote in message
...
I don't want to be unduly pessimistic, but Sony's 8mm transports are, to
put
it kindly, delicate. I had the transport in a HandyCam and home VCR fail
for
no obvious reason, with parts bending or breaking. The VCR is currently
non-functional, with erratic loading.

Narrow tape formats require small transport components, which are
difficult
to make "robust".

William Sommerwerck wrote:

I don't want to be unduly pessimistic, but Sony's 8mm transports are, to put
it kindly, delicate. I had the transport in a HandyCam and home VCR fail for
no obvious reason, with parts bending or breaking. The VCR is currently
non-functional, with erratic loading.

Narrow tape formats require small transport components, which are difficult
to make "robust".



Its too bad that there wasn't cross-licensing with Exabyte; the EXB8900
transport is the model of robustness and elegance with few moving parts
beyond motors. It could have been the basis for 8mm video products as
well. I recommend reading the patent literature online for detailed
descriptions of the Mammoth transport.

Michael

"Meat Plow" wrote in message
...

I just sold a Sony Digital 8 camera I bought in 2000 that was well
used but perfect in function. If the mech is treated with respect and
warnings followed there isn't any reason it should unduly fail under
normal use for many years. I would say this is the case in the
majority the minority being misuse and manufacturing QC.

I wish that were so, but I've had two analog units fail -- and I'm not aware
of having abused them. In both cases, the failures were abrupt, and not
preceded by any action that might have caused them (that I'm aware of).

For what it's worth... I rarely have problems with any of my electronics or
photographic equipment.

If anyone has a SONY service manual for the EV C3 model and the U mechanism,
and/or the tiny belts and pinch roller, that they would like to sell, please
let me know.
wb(underscore)wildbill at yahoodotcom

I tried using a small 2-AA battery holder with plain leads to check the tape
loading motor operation of running the guide bloks forward and back several
times, and noticed no resistance to movement or jamming.

Then I made a 3-AA tester "motor exerciser box" using a battery box and a
DPDT and a momentry switch, with clip leads, for easier/more reliable
reversing of the motor, and ran it thru many more cycles with the same
results.
There is no tape in place for these tests, since I would need to have
control of more functions of the Syscon board, such as the reel spindles and
possibly brakes.
I did try putting a rubber band on the guide posts (individually) to add a
little load, but the guide post blocks still operated as they should.

As mentioned earlier, the weird operation is the tape guide blocks running
back 'n forth while trying to unload the tape (before Syscon even activates
Cassette Eject).

It looks as if Syscon can't make up it's mind which way to move the tape
guide blocks to unload the tape.

Unload tape, Start
Starting, OK
Wait a sec, other way
Other way, OK
Uh-oh, wrong way
Huh?
Go back
Going back, OK
No wait, reverse
Reversing, OK
Nevermind, taking too long
Nevermind, OK
Quit now
Quit, OK
Breaktime!
Naptime, OK

As anyone knows that's ever serviced these small machines or camcorders,
it's difficult to run the mechanisms thru the various functions to see
what's happening, if one doesn't have all the various extension cables to
enable the mechanism to run outside of the main unit chassis.

Reel sensors were cleaned? with gas duster, although the interior of this
machine was extremely clean.
Mode switch had a couple of drops of DeoxIT applied, not removed for
examination, although it's probably the next best place to look for
trouble.. damage/wear, dirt or oxidation.
Mechanical load parts have had a minute amout of grease added after cleaning
off excess. The underside of the mechanism appears to be undamaged.
The reel spindles turn freely with the machine off and unloaded.

It looks a little odd, that if I stop one guide post block (with tension on
the rubber band), the guide post block on the other side continues to
travel.. I dunno if that's normal or not.

--
Cheers,
WB
..............

As this project continues (drags on).. I disovered that the bottom large
board swings out, so there is fairly good visual access to the bottom of the
transport mechanism, after the Servo/Syscon board is also swung out of the
way.

With the top and bottom covers off, and the unit standing up on it's right
side (facing the front), the bottom board is attached to hinged signal
connectors, so it can swing down to the benchtop after 2 screws are removed.
Then the Servo/Syscon board directly under the mechanism can be unlatched
and swung down after removing 1 screw, and releasing the capstan motor
harness from the plastic anchor.

It may be necessary to connect some temporary jumpers from the pads where
the removed screws would ground the boards, to the chassis, in order for the
board grounds to be maintained.
I thought I had them both grounded properly, but the key funtions (FF, Rew
etc) didn't work while I had the boards dropped down.
However, Eject did work smoothly a few times, without floundering.

After this initial test, I put the boards back in place with the screws, and
tested cassette loading and numerous Eject cycles without any problems.

With a little more manipulation, the ribbon cable in the corner of the
Servo/Syscon board can be coaxed to come out of the corner where it's folded
over, so some more range of movement is possible to get the board down and
away from the transport mechanism.
The Mode Switch still isn't visible, as it's view is blocked by the small
board at the front, but the majority of the mechanism is visible.

While examining the bottom large board (Video, Video I/O, RF Block, Jog), I
noticed that C219 470uF 10V (Red case, Long Life brand) was wet around the
seal. This cap is a radial lead type, but the leads are bent 90 degrees, so
it will lay on it's side on the board.
After replacing C219, I put a little DeoxIT on the hinged connectors along
the edge of the board, since moving the board after so long could cause bad
connections.

So, without knowing what was the cause of the problem of the floundering
guide post blocks, the proper operation of tape loading and unloading during
Eject has been restored.

After replacing the leaky surface mount caps in the head amp, and an
adjustment/alignment of the tape path, this machine may just operate again.

--
Cheers,
WB
..............

I have an EV-C3 which needs help. We'd love to get it running again sowe can view some of military time footage. Can you help? Or know a source of help. Thanks. Bill


On Tuesday, June 16, 2009 at 1:30:27 AM UTC-4, Wild_Bill wrote:
Hi, I haven't worked on VCRs for years, but I have a recent interest in 8mm
and Hi8 equipment lately, since the gear is so compact, and some of it
operates away from an AC power soure (DC powered) for remote use.
I still have enough test equipment and safe habits to get by with.

I spotted a used SONY EV C3 8mm VCR (approx 20 years old) at a recent
hamfest, and since it was only $5, I thought I'd get it to see if it was
going to be worthwhile to repair (the nice seller did at least inform me
that it did not work).
While this unit isn't commercial grade, it was cheap enough for curiousity's
sake anyway.

I've done some homework to look up SONY 8mm faults in the archives, and
believe the leaky smt electrolytics in the head amp (all 11 of 'em) repair
tip is definitely accurate for a deck of this vintage with the problem of
playing slow.
The other transport functions operate normally, except Eject. I haven't
tried recording yet, because there isn't much use in it's present condition.

Anyway, the interior of the unit seemed exceptionally clean, and testing
with a pre-recorded tape displayed poor video and audio (appears like very
bad tracking).. unsteady, slow and jittery.

From earlier experience with SONY 8mm gear, I was familiar with loose guide
posts and the resulting poor performance which has always looked as
described, but not necessarily playing slow.
The adjustable guide posts are loose enough to turn with fingertips, so
that's part of the playback problem.

The Unload/Eject problem has me confused (not a difficult situation anymore)
as the tape unloading operation is jerky, and the guide post blocks run back
'n forth while trying to accomplish unloading.
Some times, they stop in the middle and the power can be shut off, then
turned back on to retry Eject.
This might work in one try or may take 3 tries, but then the cassette ejects
quickly when the guide post blocks have reached the fully unloaded position.
There appears to be adequate lubrication on the underside of the mode gear
and associated parts, as I added just a very slight amount for surfaces of
the moving parts.

I don't understand the jerky, back 'n forth motion of the guide posts..
stopping and moving would seem normal, but running forward and reverse has
me baffled.
Would anyone care to enlighten me as to why this might be happening?

I haven't removed the mode switch for examination, but I did drip a couple
of drops of DeoxIT (not flooded) into the switch before running the
mechanism thru numerous cyles, with no change.

There appear to be only 2 very small/tiny cogged belts in this mechanism
(somewhere noted to be the U mechanism that's also used in commercial
units).

Thanks for any insight.

--
Cheers,
WB
..................

There are a number of potential problems with this mostly due to age. What is the problem? Also, where are you located? There are some of us able to repair these, but a location is required.

Thanks,
Dan

wrote in message
...
There are a number of potential problems with this mostly due to age.
What is the problem? Also, where are you located? There are some of us
able to repair these, but a location is required.

The older VHS decks had a "lighthouse" bulb sticking up into the cassette
for end sensors at each side to detect the clear leader at the ends of the
tape - what it does when the bulb blows depends on the firmware. A common
symptom is; won't come out of standby.

Later ones had an LED on the post, which almost never failed.

No idea whether the 8mm has one - but I'd look to see.