Heaven's VBXE works - after 6 hours on the CRT battlefield
- Published: Saturday, 26 December 2015 00:00
- Hits: 2373
At Revision in April 2015 Heaven gave me his Atari 130 XE and his Atari 65 XE with VBXE 2.0 installed. The first one had broken down at the party, the second one has a VBXE built in but not adapter cable to connect it to a TV. While the Atari 130 XE worked fine after a little cleaning and re-soldering, the VBXE machine turned out to have an Atari ST monitor connector and a complex switch built in. I sat down for some hours and traced the different signals through all the wires, the switch and the connector. I found that the way the wiring was, the connector can server as FBAS-SCART and RGB- SCART at the same time, depending on the switch position. But I didn't have a proper plug for the connector, so I first had to order one. I had to learn the hard way that there are different types of 8-pin DIN plug with slightly different pin arrangement, none actually fully matches the Atari ST monitor connector.
Months went by and finally I got a working plug, but I was frightened by the thought of soldering SCART cables with 21 pins into the damn tiny DIN plug, no knowing where color meant what and which pin is actually which (plug vs. connector, front-view vs. rear-view, ST plug vs. VBXE pinout, before the switch vs. after the switch....). And guess what: How right I was.
Today I was in the mood and decided to give it a try. 3 hours of soldering, measuring, desoldering, measuring, re-soldering, dozens of mapping lists and diagrams I finally made it. And then, when the cable was complete, I tested it. And it didn't work at all with my SABA CRT. So a started measuring, desoldering, measuring, re-soldering, checked the diagrams again and again. Then I tried the 2nd CRT (Goldstar). It gave a very dark b/w picture and no VBXE picture at all . The 3rd CRT (Grundig) gave the same result. Meanwhile I was 100% sure that the wiring was fine. CRT number 4 (Schneider) then gave a clear picture with greyscales - in red. IN RED ?!?! Back to the board, did I swap luma with red - no I'm not that stupid. Phew, no, I'm not. The 5th CRT (Sony Triniton) presented a totally distorted picture as it didn't detect that the input was on RGB and not FBAS. Finally I grabbed my (almost) last available CRT: The Phillips that had just left my living room before X-mas. I plugged it in and WHOOOA - it f-cking worked. It just worked and looked perfect. The cable had been correct right from the start, but it took 2 hours to find the TV that could actually handle RGB via SCART. Priceless. Merry Christmas Heaven, you'll get your present soon! Here's how CRT battlefield looked like.