I tend to smoke (shame on me ), so everything that vaguely looks like this looks like a lighter to me. Dave, what are you going to burn besides EPROMS?
----------------------------------------------------------------------------------- QLick here for the Back 2 the QL Blog http://backtotheql.blogspot.co.uk/
Sinclair keeping traditional hand solderers in work...
Mark
Standby alert
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer in Somerset later in the year
QL, Falcon, Atari 520STFM, Atari 1040STE, more PC's than I care to count and an assortment of 8 bit micros (Sinclair and Acorn)(nearly forgot the Psion's)
On US QLs, the interrupt runs at 50 Hz in monitor mode, and 59.94 Hz in TV mode, because their NTSC frame rate was 29.97 Hz interlaced, or 59.94 Hz. Their TV was also limited to 525 lines of which only 483 were displayable, so the JSU ROM had changes in font drawing and default channel positioning. It is something like the QL equivalent of reading a large print book.
Timing related functions behave differently in TV vs. monitor mode.
Dave wrote:On US QLs, the interrupt runs at 50 Hz in monitor mode, and 59.94 Hz in TV mode, because their NTSC frame rate was 29.97 Hz interlaced, or 59.94 Hz. Their TV was also limited to 525 lines of which only 483 were displayable, so the JSU ROM had changes in font drawing and default channel positioning. It is something like the QL equivalent of reading a large print book.
Timing related functions behave differently in TV vs. monitor mode.
The Cs across the RAM chips and CPU as well as the diodes on the 8301 are standard modifications to Samsung QLs, my German one has the same.
The piggy-pack board with the 74HCTsomething and the four blobs that I can't identify seems to be a special mod for US models. That's not in my Samsung QL.
tofro wrote:The Cs across the RAM chips and CPU as well as the diodes on the 8301 are standard modifications to Samsung QLs, my German one has the same.
The piggy-pack board with the 74HCTsomething and the four blobs that I can't identify seems to be a special mod for US models. That's not in my Samsung QL.
Tobias
The diodes across 8301 are protection diodes for RGB outputs to prevent spikes created by hot-plugging or unplugging the monitor cable from damaging them. The blobs are silicon glue to hold the board in place