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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Orihalcon on December 02, 2024, 10:23:03 pm

Title: Advice on where to add S-Video output lines to Betamax player?
Post by: Orihalcon on December 02, 2024, 10:23:03 pm
Hello all, I want to try "S-Video Output Modding" a Sony SL-HF900 Super Betamax player, but I need help determining where I'd need to actually tap luma and chroma for the mod (and if any other components need to be added such as 0.1uf capacitors to the chroma and luma lines).

I've attached a truncated service manual that only shows information that should pertain to an S-Video mod. I can see several candidates of where you'd tap as the service manual does show various separated chroma and luma signals. The ones we are interested in are the "PB" chroma and luma levels as that is for "Playback". "REC" levels aren't useful here because that would be levels to record onto a tape and these days betamax is mainly used to capture video from rather than make new betamax recordings.

Would love to try different suggestions and I'll report back if the S-Video mod was successful!
Title: Re: Advice on where to add S-Video output lines to Betamax player?
Post by: coromonadalix on December 04, 2024, 02:40:30 am
you received answers on this forum i think

https://www.digitalfaq.com/forum/vcr-repair/14789-betamax-video-mod.html (https://www.digitalfaq.com/forum/vcr-repair/14789-betamax-video-mod.html)
Title: Re: Advice on where to add S-Video output lines to Betamax player?
Post by: NiHaoMike on December 04, 2024, 03:04:56 am
If you're trying to archive videos, consider a mod to digitize the raw signals instead.
https://github.com/oyvindln/vhs-decode
Title: Re: Advice on where to add S-Video output lines to Betamax player?
Post by: Orihalcon on December 04, 2024, 10:19:07 pm
Nah, nothing useful in those replies. hence why I'm posting here where there's more likely to be an EE that is familiar with composite/S-Video circuit design.  I feel like all the information needed to come up with the solution is present in that attached PDF, I just do not have the expertise to know how to hook it up exactly without harming the equipment or if additional components should be placed in line and why.
Title: Re: Advice on where to add S-Video output lines to Betamax player?
Post by: jh15 on December 04, 2024, 10:28:40 pm
An external comb filter? In some video displays, years ago, the comb filters did a great job internally. I wonder if there are external comb filters to split the luma and chroma signals.
Title: Re: Advice on where to add S-Video output lines to Betamax player?
Post by: Benta on December 04, 2024, 10:58:31 pm
Quote from: Orihalcon on December 02, 2024, 10:23:03 pm
Hello all, I want to try "S-Video Output Modding" a Sony SL-HF900 Super Betamax player,
Could you explain the rationale for this "mod"?
In my experience, the S-Video output from VCRs is not as good as the normal CVBS, and my reconding/conversion devices often complain.
S-Video is great when delivered directly from the source (eg, video cam), but inferior in other situations.