Hi y'all - my Aiwa VCR, which up until today had been playing tapes without issue, has developed this static-positioned distorted horizontal line across all tapes I've tried. It actually appears more like clustered small vertical lines spread out horizontally across the screen. Standard play, EP or LP, commercial tapes/any tapes - some form of this distorted line exists, in the upper half of the screen.

Here is a link to a video with an example of the problem - https://www.dropbox.com/scl/fi/o786mf9l0cl06kkjgw98u/20261022_213211_394_657.mov?rlkey=chq9plchd7k40em0 0syfkirv8&st=w38u8h44&dl=0

I have thoroughly cleaned the head and all guides and areas the tape interacts with. Adjusting tracking does not help. Some tapes worse than others, although haven't sorted out a pattern.

Are one of the heads just wearing down? Possibly something deeper stuck there? Hoping there might be some insight from someone who has experienced this before.


Cheers

A fixed vertical position would be related to a problem at a fixed position on the head drum, not a head. Looking at the position of the disturbance on the screen should give you an idea of where around the drum the problem is.

Second thought: instead of a defect on the stationary part of the drum, could it be a defect in the signal coupling mechanism from the rotating drum to the rest of the circuitry?

Hopefully soeone with more experience will chime in. Good luck!

.

This describes the signal transfer from the heads:
https://en.wikipedia.org/wiki/Rotary_transformer
Could still be dirty heads, or try demagnetizing the heads with a small
pencil sized tape head demagnetizer. I had one from Radio Shack,
looked like a pencil. We use to clean the heads on the drum with
Alcohol first, then a VRC Q-Tip full of Freeze (in those days Freon)
Worked well..... I think the cold temps caused the contaminants
to flake off the heads - Company Reps said to do it that way
so that's what we did....

https://www.ebay.com/itm/178145532551

VCR Q-Tips seemed to be made of the softer part of Velcro
not the hook part, and they were flat, and after Freezing
it, you placed it on the drum before the head and moved
it past the head with the direction of rotation only, not
up and down but moving as if it was the video tape
on the heads in normal operation.

You'll want to watch the system in operation as well,
be sure the tape is not being bent as it moves
past all of the tape guides. By Bent I mean
if a guide is moved, it's limits may push
on the top or bottom of the tape and you
can see the tape distort from it's flat
orientation as it moves... Not likely.
Don't turn anything.....

Anyway, the noise is hitting the blue key
on the piano, so it's got a specific
frequency note to it.... Check
the plug for the pickup where
it goes to the main board.
Dirty noisy contacts.

.

For my enlightenment:

Is the rotating part of the head drum powered in any way, or is it only coupling the low level head signals?

.

In everything I have seen the spinning tape head is attached to the motor shaft,
and the motor body with all the works is mounted to the main metal frame to
the VCR. Motor is multi-pole brushless etc.

.

I meant, is there powered video circuitry on the rotating part of the drum?

.


The rotating part of the drum only has the tape heads and the transfer
coupling transformer parts on the underside. The Rotary Primary
Side I guess you would call it.... Secondary would be
mounted under the drum not visible.



.

.

The rotating part of the drum only has the tape heads and the transfer
coupling transformer parts on the underside. The Rotary Primary
Side I guess you would call it.... Secondary would be
mounted under the drum not visible.

.

Thanks

.

This describes the signal transfer from the heads:
https://en.wikipedia.org/wiki/Rotary_transformer
Could still be dirty heads, or try demagnetizing the heads with a small
pencil sized tape head demagnetizer. I had one from Radio Shack,
looked like a pencil. We use to clean the heads on the drum with
Alcohol first, then a VRC Q-Tip full of Freeze (in those days Freon)
Worked well..... I think the cold temps caused the contaminants
to flake off the heads - Company Reps said to do it that way
so that's what we did....

https://www.ebay.com/itm/178145532551

VCR Q-Tips seemed to be made of the softer part of Velcro
not the hook part, and they were flat, and after Freezing
it, you placed it on the drum before the head and moved
it past the head with the direction of rotation only, not
up and down but moving as if it was the video tape
on the heads in normal operation.

You'll want to watch the system in operation as well,
be sure the tape is not being bent as it moves
past all of the tape guides. By Bent I mean
if a guide is moved, it's limits may push
on the top or bottom of the tape and you
can see the tape distort from it's flat
orientation as it moves... Not likely.
Don't turn anything.....

Anyway, the noise is hitting the blue key
on the piano, so it's got a specific
frequency note to it.... Check
the plug for the pickup where
it goes to the main board.
Dirty noisy contacts.

.

Would a demag tool used for cassette tape heads be alright? I have one of those.

Contacts from the head to the board seem to be alright but I unplugged and cleaned them all for good measure. Observing the tape while playing all looks clean too, smooth, no bends. Audio is fine. Tracking otherwise good save for this half-inch distorted bar.

I will try the freeze on the heads. Is it just resting the VRC q-tip against it after spraying on the freeze? Or any type of motion against them?

Thanks in advance

.

After Freezing The Q-Tip, you place it on the drum before the head and move
it past the head with the direction of rotation only, not up and down but
moving as if it was the video tape on the heads in normal operation.

Demagnetize The Head using a Cassette demagnetizer tool just as you would
a regular cassette player head, move across the VCR heads each one and
move away from the entire unit before turning it off. Same as if you
were degaussing a picture tube.

If all this does not work, you have to play a tape and disconnect the pickup from
the tape head and see if it still makes noise in that spot. If the head connections
can be disconnected before the Rotary Coupling Transformer that might be a
good thing to try....

After that, you could get a service manual and see if there is a gain control
that you can try and tweek on it.... Some units have several controls
as mini pots that can increase gain & stuff like that.... Last resort.

.

NO Q-Tips near the video head! Use a folded piece of copy paper saturated in the purest alcohol you can get. Freon TF has been gone for many years. It did not freeze the heads. It was an excellent solvent. I've never seen any cleaning sticks made from velcro. I have seen them made from chamois.