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Documentation about the Vampire hardware

Vampire V600 HDMI Resistors/Capacitors

Leigh Russ

Posts 151
04 Jun 2018 13:14


Hi,

This is probably more a question for Majsta I guess.

After having got my Vampire pretty stable following the socket change, I would like to get the intermittent screen blackouts resolved as much as possible. Lower resolutions and pixel clocks partially resolve the issue but I have seen quite a few people have greatly improved this by changing the DIGITAL-VIDEO resisters from the current 270ohm values (more info here https://www.a1k.org/forum/showthread.php?t=61776)

I can see that the V500 and V600 v2.1 (and some v2 cards) has less of these blackout issues reported, and notice that they all have capacitors in place of these resisters.

So my question is what it is better to swap these to, 27ohm resisters instead of the 270ohm which better suits the DIGITAL-VIDEO signal level, or to swap them for capacitors. if capacitors then what value (I have seen 100nf mentioned).

Thanks.



Igor Majstorovic
(Apollo Team Member)
Posts 406
04 Jun 2018 19:44


I wouldn't recommend doing that replacement if you didn't work before with 0603 size. If you did then feel free to replace those resistors with 100nF caps. Please when you replace them measure everything in detail for the shorts.


Leigh Russ

Posts 151
04 Jun 2018 20:09


Yeah no problem, I haven't a problem doing it as used to work on SMD stuff and still dabble in rework and stuff now, was just checking what values were the preferred. Cheer Igor, much appreciated


Andrea Ottaviani

Posts 35
06 Jun 2018 06:49


Interested in reducing hdmi blackout roo, but can't access the forum posted above: which are the resistor to replace with 0603 caps?


Leigh Russ

Posts 151
06 Jun 2018 08:41


There's a PDF guide of fixes in the A1k forum post. To access it you just need to sign up.

It looks like someone shared it in the Vampire Facebook group too EXTERNAL LINK


Andrea Ottaviani

Posts 35
06 Jun 2018 18:01


Thank you.. Subscription to a1k forum are closed at the moment

posts 6