What VHS error is this? Would TBC fix it?
 

So it was all going well until it wasn't.

I've gone through quite a few tapes with my Panasonic NV-830 + ES10 setup and it has been wonderful. No dropped frames or anything. Now I have this tape which clearly has some sort of issue. What actually causes this? Would a TBC be even able to fix this?

Here's an uncompressed clip:
https://send.firefox.com/download/3b...y98Zkp1h_CILTA

It appears to be a compounded error. Bad tracking has overrun the minimal TBC(ish) abilities of the ES10. External framesync TBC would probably resolve some of it, but tracking obviously us the task of the VCR.

It may be misalign recorded, meaning a misaligned deck is required. But do NOT misalign a Panasonic, leave that task for specific JVCs, probably low-end models. (I use an SR-V101 for misalignment, but I also have many VCRs.)

So I can take one of my old VCR from storage, try and find an alignment guide on YouTube and try and track it that way?
Pity I'll have no access to my older VCR for a while with lock-down, but I'd definitely be up for trying this! Cheers for the advice lodsmurf :D

I went and bought a remote for the VCR so I could enable manual tracking. I was able to get it into a stablish state and got a half decent capture for it. Audio is still very "warbily" though.

The link has expired, but yeah, if it's a misaligned recording, you can try to realign a cheaper VCR to it, if it works it will probably look better than a misaligned recording from the SVHS deck, provided you have the ES10 in the chain.

I want to make an update on this as it might be helpful to someone else. I got another around 25+ year old tape and it had the exact same issue. I was starting to wonder if maybe the same VCR was used for both.

Anyway, I tried my tracking trick, no dice. Didn't make a difference. When I started to think back to how I fixed the last one, I played it a load of times trying to get it right. On a hunch, I high speed fast forwarded and re-winded the tape a bunch of times. Issue is now mostly fixed!

Are the tapes just jammed up and it's actually the fast forward/rewind that's fixing it?

That is a possibility. "Stiction" is the term I've heard used in TV(which is my industry). The tape could, by either being slightly sticky or even "packed" strangely on the supply reel, have caused enough of a tension error to contribute to a problem. In the late 90's, I know for a fact that we had that issue with Digital Betacam 2-hour tapes. If we didn't fast forward and then rewind them, we often had issues with mistracking on playback.