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extended BOM added
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@@ -183,3 +183,6 @@ The only difference with the ZX-81 hardware wise that for PCB needs to be fixed
# Correction in placement file swapping the values of R56 and R59 for better tape loading and saving
I was told that a Facebook poster in the ZX-81 owners group claimed he found an error in the component placement drawing, after investigation I found not one, but two errors! The creating of this drawing is a completely manual process, so human errors can occur, and in fact the drawing has been repaired several times. This latest drawing now show that the resistor that is R59 and was labelled 47K was in fact 10K, and the resistor R56 that was labelled 10K was in fact 47K. So I wisakenly swapped the two resistor values, because I mis-identified them while creating the drawing. These two errors change the levels of the output voltage and input voltage (needed) for the cassette input and output levels, so if you have difficulty with loading or saving please check you have placed the right resistor values for R59 and R56. The component placement drawing is now correct (March 17, 2024) the values in the schematic, and BOM remain correct. I'm now a member of the ZX-81 owners facebook group, so you can ask me questions there!
# Second extended BOM (bill of materials) to find hard to get parts.
This BOM has multiple suppliers, so improve the chance of finding a part you need. Created because a builder complained he could not find a part anywhere, so I added two ther suppliers to farnell, namely mouser and reicelt. It can also be used to compare the same part from to suppliers, so you can order his part from any other supplier. The new BOM is called "EXTENDED ZX81plus38_BOM_with multiple suppliers revision 1.10.ods" it can be opened with the free and open source spreadsheet open office, or any other spreadsheet that can handle .ods spreadsheet.