Amiga Syncdoubler This circuit allows the Amiga users to kostenguenstige way A PalHiresScreen on a VGA monitor display. The Darzu Amiga line synchronous pulse phase doubled. Technical: The Amiga Hsync triggers IC1a and IC1b with the positive edge, is Ic1a 4us set approximately equal to the VGA Sync, IC1b at 32us. After these 32us (Half Amiga line!) Will be triggered Ic1 again, and that was it! Line X Line X+1 ______________________________ _______________________ Amiga Hsync: __| |__| Xa Xb X+1a X+1b _ _______________ _______________ ____________ _______ gen. VGAsync: |_| |_| |_| |_| ________________ ________________ Pin13 | |_______________| |_________ None Image None Image Construction: The construction is happening fastest in a matrix board, dimensions: Approximately 2.5 x 5 cm if one takes spindle trimmer (recommended). A layout, which aetzen and to build on a matrix board - Is suitable, is attached. In the AmigaVGAAdapter now needs only the Hsync - Trace followed with a combined Syncdoubler (pin or 11 pin 10, compsync). The 5Volt for power supply are simply picked from the IC. Functional Test: If you are not so sure whether the built now that's what it will , The following can function test durchfuehren: the two C's will 470uF with ueberbrueckt and at the output (pin 12) is a light-emitting diode . This muesste then burn (VCC = 5Volt not forget!). Per Hand is a positive change flank simulated. The Leuchdiode should now Twice in a row and acceptable. Balance: To balance reaches a multimeter. In the adjoining state and the Amiga Sync at the entrance, the voltage at the output of IC1a (Pin13) 2.5 Volt (half VCC) is set, then the equivalent of a Tastverhaeltnis 1:1. On the second Poti (2K of IC1b) is rotated until now to the VGA Monitor synchronized. Now must the left and the right half of the Amiga ueberlagert screens on the monitor to see. To the two sides And selected separately to see, you need the following addition: Three transistors (BC 547), about three Vorwiderstaende (1K) IC1a activated (pin or 13 pin 4), depending on the pin is the left or the Bildhaelfte right watch, a once switcher provides for the selection. The transistors close the RGB signal short (of mass emitter, collector An R, G and B). Compositions list: 1x74Ls123 2x10nF 1xSpindeltrimmer 2K 1xSpindeltrimmer 5K 1x100nF 3x1K 3xBC547 1XUmschlter 1xLochrasterplatine 2.5 x 5cm Pin from the video port: Red 3 4 Gruen 5 blue 10 compsync 23 5V 16-20 Mass This circuit has been successfully in an A4000 with a VisionMaster17 And in a Yakumo tested. The Syncdoubler has the following features: - Extremely preisguentig Compatible with any software as hardware - Compatible with doublePal, MultiScan Standard Parts Just the left - This hardware is mail product, send me mail if your ne uses when There are suggestions, or just so. Bye, Dirk Fido 2:2432 / 360.6 BBS: 0515598138 InterNet Dirk_Duesterberg@p6.f360.n2432.z2.ftg.donut.de