VHS tape goes black every few seconds?
 

hello everyone:)
i have a aiwa g100 vcr. when playing in some vhs tapes video and audio plays for couple of seconds then things go black then i see some line noise in the whole screen and this cycle repeats mean while the tape is rolling and its not stopped. i have a lots of tapes that plays fine without any problem. when this problematic vhs tapes are playing the tape speed indicator on vcr screen is constantly changing between LP and Sp and there is incensement of noise from vcr periodically. the situation does not change weather the vcr is in auto tracking mode or manual. the strange thing is that when i fast forward everything plays normal and there is no black/noise part.
i have tried to change the tape frame to one of the other working tapes but that didnt do anything also tape of problematic vhs look fine to me.

any advice on why is this happening and how to fix it is appreciated

This is either a tape format your VCR cannot playback (PAL, SECAM, NTSC, PAL M, MESECAM ....) or one of the oddball low speed recorded on another VCR that your actual VCR cannot handle it, Low speeds are not part of the original VHS standard so every manufacturer had their own tolerances.

im certain that all the footage were recorded with a Panasonic slim palm recorder (NV-RX10EN) which works in PAL and according to my vcr manual it support PAL/MESECAM.
i think they were converted from VHS-C to Vhs by pluging the camera to Tv and recording with the same vcr. the only other possibility is that the VHS-C was put into a cassette adaptor and then it was put into vcr(1) and out put of vcr(1) was recorded by vcr(2).
with all that said is what you suggested still a possibility ?

Typical problems you encounter from going VHS-C to full VHS or vise versa, It's explained here.

what i dont understand is that why is this happening only to some tapes and not the others seeing that all were VHS-C and were converted in the same manner.

I don't buy the "VHS-C to VHS conversion" as being the problem here. Or really a problem ever.

That's a multisystem Aiwa, right? Same as Samsungs and Panasonics. Lots of issues with those. Most issues disappear entirely when played in quality NTSC or PAL decks (JVC S-VHS with line TBCs models). The reason I bought a PAL deck decades ago was because the Samsung was giving me poor playback on some tapes, randomly.

Don't be too certain about tapes. People misremember all the time. No label/notes with the tape, you really have no idea anymore.

First put the capture gear a side, you need to hookup to a TV to see what noise pattern you have, Post a short clip with the phone from the TV screen, If the noise pattern is miss tracking then you will have to find a cheap VCR and try to re-align it to get better playback, You get a better chance if the the VHS-C tape was recorded in SP, LP complicates things due to way VHS-C is recorded with a small video drum, Good luck.

Or pay somebody to do it.

The problem with cheap VCR is then playback quality. Not that that Aiwa was much better, lousy player, no TBCs, lots of other quality issues. The video honestly sucks.

I have a JVC S-VHS decks (with line TBC) that I misalign for problem tapes.

Btw, PAL people do not need to buy , they can rent quality VCRs from VCRshop.nl

@lordsmurf
@latreche34
Thanks for your help.
I attached a Short Sample that i recorded with my phone.
I think Lordsmurf is correct that this is a vcr problem because i found some of the vhs-c tapes and they play fine with a adaptor. and i think (im not sure) i used to play some of these now problamatic tapes before with out any issues.
Attachment 14730

The sample confirms that it is not an alignment problem so you're lucky, but the VCR is not locking on that tape speed, This doesn't mean the VCR is bad, it is just not recognizing the tape as a standard within its scope as I explained in post #2.