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VCR, simple maintenance of

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Rigid

New Member
Greetings, engineers. A year has passed since I bought my VCR and lo, as the warranty expires, the problem starts - the same problem that caused me to ditch our last VCR - crap recordings that sound awful and seemingly can't track properly. I'm told it is probably a bit of dirt on the ACE assembly. Not sure what that is, but apparently cleaning it involves little more than a cotton bud and some meths. Can any enlightened one tell me what the ACE assembly looks like (it's a Toshiba VCR, but my guess is an ACE is an ACE), and how to clean it successfully without a) destroying the machine and b) killing myself with an electrical discharge. Thanks...
 

kinjalgp

Active Member
I don't know what ACE means but normally when you get poor sound/picture quality from VCR you have to clean its DRUM HEAD. Its a silver color part which reads the magnetic contents of TAPE. When dust covers its surface, the reading is not done properly and hence the poor result. Try cleaning this drum with either Head Cleaning Cassette or Speacial Head Cleaning Fluid easily available in Video Stores. You can see this drum exactly in front of the slot where you insert the cassette.
 

Rigid

New Member
Thanks, kinjalgp, but if the drum head was dirty wouldn't that also affect playback of pre-recorded tapes? The thing is, playback of bought tapes is perfect, only tapes we have recorded ourselves are bad. The guy I spoke to said something about the control pulse used to record nicam sound and the Acoustic - - (The A in ACE) component which MUST be perfectly clean to function properly. I wonder if a regular head cleaning cassette would reach this part...
 

margaret

New Member
vtr maintenance.

VTR maintenance for the average punter in my experience of 30 years of repairing them, (now old hat) is that when the video heads became clogged with iron oxide from tapes that were worn or maybe dust covered , near a source of heat, or alternatively worn video heads that were more prone to clogging because they had less surface area to bite onto the magnetic tape, this was usually the cause of no video,.. talking about magnetic tape it is heavy and if left flat (horizontally) tends to cone, in some vtr's this could effect the tracking,. some earlier vtr's had a separate pulse ctl head, also by itself the audio head, later both were combined in the same unit.

Common mistakes by punters were in the absence of video on screen the word on the street was to give the large chrome drum a good scrubbing, as time progressed the small coil encaptulated heads became common knowledge, this resulted in broken heads galore usually the head and lower drum were scratched.

ACE?..... common vtr's have combination audio / ctl heads, the erase head is to the left activated as pre-rec material enters the lacing procedure under the command record.
 

margaret

New Member
vtr maintenance.

Forgot to mention: basic cleaning methods that i have used for years with good results, tape cleaners can improve a situation but if you need to use these in the first place this could be a sign that the machine needs a more direct approach which will involve removing the top cover from the vtr.

Before you do this however, bear in mind that some parts inside are live and lethal, especially to someone "with respect" that throws caution to the wind and decides to clean the vtr with mains voltage applied, some earlier machines may have used a TX to drop the mains voltage to the psu, even so the mains input supply will still be at the primary of the TX ( mains transformer) with a supply of us/115vac or uk 250vac with a mains rated fuse on the primary side of the TX situated close by, carefull observation is required, in most modern machines a psu
(POWER SUPPLY UNIT) may use a SMPS, ( SWITCH MODE POWER SUPPLY) which is more lethal since some parts of the psu cct board are at mains potential, ...for cleaning maintenance remove the supply plug.


You are thinking by this time what has this got to do with giving a vtr a clean up, well some could be lulled into a false sense of security simply because electricity has no respect for anyone, being silent and invisible to us mere mortals conventially, never the less it is swift and could be deadly if mis-used, many years ago a nearby neighbour decided to extend his kitchen mains appliance skt's taking a spur from an existing skt for his washing machine, the simple error he made that day killed him months later when checking the inside of his faulty washing machine, ...he had switched the machine off at the skt leaving the plug in the :roll: skt thinking this was sufficient but his earlier DIY skt extension proved fatal simply because he had transposed the wiring in this extra skt so that where he thought the washing machine was isolated the live wire was still supplying the machine effectively bypassing the switch, contact with the metal body and a live internal part proved tragic.

NB: to be continued.
 

margaret

New Member
simple vtr maintenance part 2.

:D Continuing from where i left off, even in these times of dvd play/rec, the amount of vtrs still being used including myself must be many worldwide and a simple guide to maintain them may help some people who feel that the whirring and clicks from inside their machines is daunting.

Anything that moves wears, simple maintenance could help to reduce problems from occurring earlier than necessary the electronic side of vtrs are another matter all together.

Bearing in mind what was mentioned in part 1,... after removing the top cover lift the machine and turn it over, any foriegn bodies inside may fall out, eg. straws, badge's, coins, small toys, buttons, sweets, i could go on but these are just some of the things i have found inside vtrs that in most cases were the original cause of malfunction, :) small children like to use the vtr as a letter box when no one is looking.

The tape deck with it's factory settings ie certain screw adjustments must be left alone what we are concerned with is the manual cleaning of the deck and it's moving parts,.

VIDEO HEAD DRUM: a large chrome like cylinder that you can see easily,... depending on the machine you have, 2 or more video heads are sandwiched between the upper and "lower drum which remains static" the spinning heads are on the upper drum and are fragile.

TAPE GUIDES: small vertical pillars with white barrels that can be rotated.

ERASE HEAD: situated to the left of the drum.

AUDIO CTL HEAD: situated to the right of the drum.

CAPSTAN ROLLER: vertical black rubber roller rhs of drum.

The layout for these parts are well known and published graphically in many books.

To be continued.
 

john1

Active Member
Hi Margaret,

Yes, i know what you mean by 'transposing the wiring'
For those who don't quite see what is meant,
he got the live and neutral wires crossed over when
he ran in an extra socket as a spur.

Thing is, most electrical appliances will run just
the same, but in this case he was switching the power
on and off in the neutral line, which was wired to the
switch inside the socket, where the live should have
been. So it behaved in a normal manner.

Unfortunately for him, sockets rarely switch both the
live and neutral lines, he had switched off the neutral
and the live was still present.

I always carry a neon screwdriver. Its such a simple
thing, yet i am sure it has saved me many times.
I have even had instances where a spur has been wired
in correctly, and yet the live is on the neutral leg.
Which of course means that where it came from is wired
in wrongly, and has been maybe for years. A simple spur
turns into a fox-hunt for the location of the place
where the wiring error occurred. Getting the neutral and
live crossed is more common than many people realise.

waiting for continuation part three ...

John :)
 
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