→The Timex Machines
* The TS2068 is an American machine operating at 60Hz on a 110v power supply and generates an NTSC television picture (just like the Spectrums sold by mail order in the US by Sinclair) but with a [[Timex TS1000|TS1000]] (ZX81) compatible expansion bus.
There are also two modified versions of the TC2048; the TC2128 (Rebuiltion or similar) and the TC2144 (by Jarek Adamski). The TC2128 extends the TC2048 to 128K using the Spectrum 128 memory scheme. The TC2144 does the same but provides an extra 16K of memory between 0x8000 and 0xc000. Both upgrades allow the ULA to use the shadow screen in Bank 7 giving the machine a total of four screen areas.
Although the Timex machines are similar to the 48K machine there are some timing differences: