BVM-A20F1M Sega consoles Sync problems

[jwrose]

Ugh, that's a bummer. The main reason I got a multi-format monitor was to use it with a Dreamcast in 480p mode. Is there no known solution for this with the clone board?

It’s possible that running it through one of Extron’s signal processors might fix it. Years back I had done that for my Neo Geo AES to fix a similar issue with the stock board. I think I had to use a processor that had the SERR feature- but I cannot guarantee that it will fix this issue. For example, my SMS doesn’t play nice with my BVM either and that same signal processor was no help fixing it.

[daty2k1]

I need to test it again but from what I remember, I don't have this issue with the clone board. Bear in mind that I have the "Xtreme" version. I use a SCART cable from RGC that can switch between 480i and 480p.

[DuxPrime]

For those coming to this thread looking for a solution, I was able to solve my Dreamcast 480p issue using this cable from Retro Access. Previously, I had been using the Mamba from Behar Bros.

I'm not sure what the important difference is. They're both 75 ohm, shielded coaxial cables with tantalum capacitors and selectable video modes. The secret sauce must be in the signal processing circuit, as the one from Retro Access uses a design by citrus3000psi.

[kamiboy]

I can confirm that using a Extron RGB 580xi you can connect both a Dreamcast and a Wii to a A20 via the original BKM module without any warping or other problems.

I am a bit miffed about having to use an extra device with the added cables and general clutter. I am tempted to sell both the Extron and the BKM to buy the reproduction BKM with various inputs and reduce the clutter to just one cable.

I wonder if one could connect one device to each inputs on that reproduction BKM and just use one at a time to get the benefit of additional inputs.

Are there any drawbacks to going with a reproduction BKM input on a BVM A series over the original?

[daty2k1]

I've had the bkm-68xtreme for over a year now (had the v1 before) and for me it's a clear upgrade over the original.

I've had zero sync problem with any console (AES, Dreamcast and Master System included) and using a VGA connection from the SVS is really convenient. Price is also not too bad now that they can use a cheaper FPGA.

Edit: I would say the only drawback could be if one needs BNC connectors in case they are daisy chaining from another pro monitor.

[kamiboy]

Do I remember wrong or did I hear mention of the reproduction BKM lacking support for some geometry stuff?

[daty2k1]

Never heard of this to be honest and there is no mention of it on the github page but I didn't verify it. Based on the following, it should not affect anything:

The digital section consists of a FPGA (efinix Trion T8Q144) with a buttload of schmitt triggers and line drivers, all replicated from the original 68X service manual. The card thus tries to be electrically similar to the original, at the interface level.