Originally Posted by systems2000
The Sunkey SK-801ATSC uses a 12VDC positive center plug at 0.8A.
Gosh, I know I'll catch crap for this...
but the fact the connectors sleeve is negative DOES NOT indicate a negative ground chassis!!!!
Sadly, a lot of eastern TV's use positive ground to save cost also, so you need to measure first, and apply power second.
No offense meant to you System 2000, I (Almost always) respect your posts.
But thats not the whole story. I wish more people would talk about external wall-wart-/power-brick CECB's and would measure their unit for true negative ground.
Does your SunKey measure a pure short from your input DC input's negative sleeve(/pin), to RF connector griound? (Assumption made you own one because your cited this item).
I say this because slightly older LCD displays (intended for american vehicle usage) are available for cheap (eBay, CraigsList.org, Etc.) ARE negative ground by design. They are intended as primary, 2nd, 3rd, Etc. displays units for (in-trunk/in dash) displays, and are eveywhere for cheap. They make awsome cost-conscious purchases to prepare for supply main loss outages (During storms, Etc.) and other outages.
I guess I should seize this opportunity to ask the kind of people that would open this thread in the first place,
to measure for a perfect short from the negative DC input lead (Collor/pin) to the RF (Ch-3/4) connector's threaded external ground (You know, the "Other" perfect short), for any externally powered CECB's with a 12-Volts DC (Or less) unit.
Thanks for feedback