* - ZX97 ROM Image can be downloaded from this LINK (Zipped) 

** - This IC is used for the keyboard matrix input port and for tape input. In certain situations it may be recommended to use a LS IC because these have a different input impedance which may positively affect maximum keyboard cable length, (capacitive load/coupling of longer wires) as well as regular program loading from audio tape or other audio sources in combination with the analog filter circuits (as described in the ZX97 Lite schematic). 

*** - These single line connectors and jumper headers can easily be made by cutting up precision IC sockets to fit the PCB positions. Similar sized pieces of precision IC sockets can be used as connectors for example for power, keyboard etc if you solder flatcable or other wiring in the IC holes. Make sure you insert the self-made connectors in a IC socket when you solder them or else the soldering heat may draw out the pins. 
From two loose precision IC socket pins you can easily make jumpers for example for the memory option or character/BG select options. Just insert two of them next to each other in a precision IC socket and solder them together using only soldering tin by holding the soldering iron between the pins while adding tin until they are merged. This should be relatively easy, at least that's my experience. 

**** - These resistor networks can easily be made by soldering precision IC sockets in their place since they are DIP devices. You can simply use 1K 1/4W resistors, bend the legs in a straight angle, cut the legs to length so they can be inserted into the DIP IC sockets. Try to keep the legs as long as possible while still inserting the resistors closely to the DIP sockets, thus getting maximum contact and mechanical stability. 
 
 

With questions I can be contacted by email

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