the Didaktik Gama and the ZX Spectrum 128K. Krišpín The Krišpín was a czechoslovakian clone of the ZX Spectrum, developed by František Kubiš at 1984, a student of EF SVŠT (Electrotechnical Faculty of Slovak Technical University) Bratislava. The ULA was designed using discrete 74xx ICs, which resulted in the screen part of RAM being synchronised perfectly, without CPU blocking. MISTRUM Another Czechoslovakian clone of the 48K ZX Spectrum, the MISTRUM, was supplied in kit form. The ROM was modified to include letters with Czech diacritic marks. An article on how to build a Mistrum was published in the Czechoslovak amateur radio magazine Amatérské Radio 1/89 – this article has since been translated into English. Nucleon The Nucleon was a Czech clone of the Pentagon 512K, made by CSS Electronics. Sparrow 48K The Sparrow 48K is the first modern clone of the ZX Spectrum designed to replace the original motherboard in standard and Spectrum+ case. Production commenced in 2013. In addition to the use of the original ULA chip, this clone was heavily modernised, replacing part of the larger glue logic with one CPLD chip, the entire main memory with one SRAM chip, and all 8 video memory chips with a second SRAM. The TV modulator has been dropped in favour of a video signal, and the PSU was changed and improved. The Sparrow also offers a larger ROM, which can be increased by 16 KB via a switch or a jumper. The successor is the Sparrow SX, with software ROM switching and RTC. East German RR-Spectrum The RR-Spectrum was a privately built East German clone of the ZX Spectrum. Spectral Spectral was another An East German clone of the ZX Spectrum. It came with a built-in joystick interface, and either 48 or 128 KB RAM. It was sold in kit form by Hübner Elektronik. Hungarian HT 3080C The HT 3080C was an Hungarian ZX Spectrum clone made by Híradástechnikai Szövetkezet (News Technology Cooperative), and released in 1986. It was the third computer from the company. The two first computers (HT 1080Z and HT 2080Z) were clones of the TRS-80, and were unsuccessful because of the poor graphics features and high price. They were both school computers. In 1986, Hungarian school computers were required to meet two criteria: produce high resolution graphics, and support letters with Hungarian diacritic marks. The HT 3080C was produced to satisfy both these criteria, and was