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hodgey 02-03-2021 07:09 AM

There is some difference in brightness/contrast between the clips. The ATI-600 is darker, I didn't check whether it's clipped at Y=16 (some capcute cards do) in the file or just during the rgb conversion on playback. For an very detailed judgement you would have to test it with some test patterns but from a first glance the GV doesn't seem to look any worse than the ATI. I also remember from a previous post that it seemed to have proper brightness/contrast adjustments for the input rather than just messing with the digitized signal like on many other USB dongles (which can result in banding).

As for the menu, the menu output in the JVC (and maybe others as well) is a bit non-standard. Firstly it's a 288p signal (a "trick" of sorts) to make a CRT screen draw each video field at the same spot. It's done by messing with the vertical synchronization signal, so it can confuse some capture devices that don't recognize it. It was commonly used in game consoles to avoid vertical jitter which can get quite noticeable on sharp text and computer graphics. Additionally, from what I've found the VCR will output the color signal on the brightness channel as well when in the menu, which is what causes the background to have a dot or line pattern. (I think the OSD chips technically only have one in/output so they just output the same on both channels). Different capture devices will react differently to this depending on how they filter the input.

I have an AVE5, in some ways it works as a TBC though I haven't stress tested it on a bunch of different inputs. It is pretty old and didn't seem entirely transparent, though I don't know to what extent it's due to aging components and to what extent it's down to just the old hardware in the one I have.

The AVT and Datavideo thingies are well tested, though hard to get and expensive.

The Philips one looks like one of the funai DVDRs. They use a panasonic chip and may have some stabilization built in, though from what others hare reported they are known to suffer from an overactive automatic gain control that can cause flickering.

If using a dvd-recorder note that they often put macrovision on the output if the input has it, so whatever capture device you use will need to be able to deal with that. Macrovision on the input will also cause the automatic gain control to go wild in dvd-recorders even if you can capture the output fine, especially in older models.

I would maybe look for DVD that helps correct horizontal jitter in any case, the TBC in the JVC/Philips VCR can sometimes be a bit unreliable if the tape signal is very unstable like with a camcorder tape with lots of movement.


My Panasonic ES15, EH-65 & EH495 have the same performance.
Hm, I have an ES10 and an EH57, I've only ever seen a slight difference on an extremely bad tape with very messed up vsync area.

I've also found that all DVD-recorders I've tested will digitize the signal on passthrough (though the panasonics like to turn off the analog outputs if there is no input for whatever reason.) They will all do something, though there are some do a very shoddy job at it. I have a store-brand unit with a TVP5146 (LSI branded) and LSI chipset which seems to easily loose sync, and a Daewoo dvd/vcr recorder combo with a mediatek chipset which is absolutely dreadful and wiggly on anything from tape sources, so that's something to avoid. Both the hardware itself and how it's set up will determine how well a unit works though.

I've noted the same things with the Sony/Pioneer and JVC ones. When re-testing the JVC DR-MH300 I have it seemed to act much worse than I remembered on bad input, I tested with the s-video out this time and HDMI out last time so maybe there's a difference between the outputs on those?

archivarious 02-18-2021 10:03 AM

5 Attachment(s)
Managed to get my hands on a few possible TBC options.

Did a quick test using s-video in and out. Encountered one blown capacitor on a TBC-1000. Suggestions on how to proceed?

- a Panasonic WJ-AVE5 video mixer. Passthrough works.
- a Panasonic DMR-EH49. Pass-through works.
- a Datavideo TBC-1000. Pass-through works.
After a few minutes: capacitor next to power BLEW with a loud audible pop. Images of blown capacitor, and the liquid burst on the roof of the device attached. Motherboard has no leakage, and is currently held upside down to prevent further damage. See pictures attached.

bookemdano 02-18-2021 10:21 AM


Looks easy enough to replace since it's through-hole design. Not sure if you have or are willing to buy a soldering iron, but I guess that would be my suggestion (unless of course you paid big bucks for the TBC-1000 and want to try to return it as defective).

If you have a multimeter you might want to measure the voltage coming from the TBC-1000's AC adapter just to make sure it's in-spec.

archivarious 02-18-2021 10:46 AM

Soldering then. Any idea why this specific one blew, should the other big ones similar to it also be replaced preventively?
Is there a way to test if all is OK? No burn smell.

bookemdano 02-18-2021 11:06 AM

I confess to having no personal experience with the TBC-1000, so maybe LordSmurf or others who have used/serviced them can comment. But from what I remember reading, capacitors aren't a common problem. That's why I suggest making sure your AC adapter is putting out the proper voltage. In addition, you should put the TBC on a power conditioner and/or UPS to help protect it from supply voltage variations/surges.

To the best of my knowledge, there is not really a good way to test capacitors while they are wired into the circuit. You can get an ESR meter but you have to unsolder each capacitor to test it. Otherwise, you can usually see bad capacitors by looking for bulged tops like the one in your photos. I don't know if you had a chance to look at it before it blew, but if so did you notice whether the top was bulging?

In the US, is a good source for electrical components. All the specs you need to replace that capacitor are printed on the side of it. If you're in Europe or elsewhere then I'm not sure what sources are available--maybe someone else can comment on that.

Edit: Looks like bad power supply caps are indeed an issue that can happen with these. See this thread for more info (including the link to another forum discussion about it):

archivarious 02-18-2021 11:18 AM

Didn't check before. Lesson learned :)
After the pop device seemed to be working still. Unplugged soon after.
I have one of those plug-in surge protectors. Would that be sufficient? I can get a UPS otherwise. Am in Europe, some local shops could help with getting the right capacitor(s)

bookemdano 02-18-2021 03:58 PM

I would get a true UPS (consider the value of the TBC-1000 alone!), but a high-quality surge protector is better than nothing.

Best of luck with the repair--the TBC-1000 is worth it! I hope you will post an update with your progress/results.

archivarious 02-27-2021 12:50 PM

2 Attachment(s)
Preparing for sending the TBC-1000 into repair at a local business.

Here's some test captures of the TBC-1000 (before the cap burst). TBC was added and removed.
Adding (TBC ON): result is slightly softer image. Removing (TBC OFF): slightly sharper image.

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