Design allows for BUS MODS OR SIGNAL PASS THROUGH but must be jumpered to go downstream
Comments here
https://docs.google.com/drawings/d/1Lai ... sp=sharing
W.R. HS4/PROTOTYPING BUSBOARD
W.R. HS4/PROTOTYPING BUSBOARD
5-TS1000,UK ZX81<-Sheelagh, US ZX81, 2-TS1500/KDLX , 3-TS2040 printer, 2-TS2020 cassette decks, ZXPAND+AY, ZeddyNET, ZXBlast, UDG, ZX8CCB, AERCO, BUILDS/REPAIRS ZX Spectrum, ZX80 Minstrel, ZXMAX48 v1 v2, 2-TS-2068, ROM, 16kRAM