Not long after the TS 2068 came out, some enterprising users figured out that they could replace the internal ROM with a Spectrum ROM and run almost all Spectrum software.
There were essentially two methods: replace the internal ROM chip with something like the ROMSWITCH or use a Spectrum ROM on a cartridge.
Initially both required an actual Spectrum ROM. Then folks figured out that they could program an EPROM with the Spectrum ROM.
Programming the EPROM, however, was not an easy task. The Timex/Sinclair’s non-standard bus and lack of standard serial or parallel ports meant options were limited to John Oliger’s EPROM Programmer. Or, if you had access to a university electronics lab or someone in industry, an EPROM programmer, like the Prompro-8 below.
Programming from the 2068
Some enterprising user figured out a way to read the contents of a Spectrum ROM into RAM and save it to tape for those who had an EPROM programmer for their 2068.
The cassette, which has the simplest instructions possible, is nothing more than a 16K CODE file.
Once loaded into RAM, the software to drive the Oliger would copy this code to the EPROM.
The EPROM would likely be used in one of the many EPROM cartridge boards available.
You can download this tape from archive.org.
