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Just been given an older 1740 (not the 1740A) vector scope. Has a Y channel fault, and also NTSC (I need PAL). I believe that there is a combined 1740 series manual available covering both standards and wonder if just the schematic might be available.
Replaced the 3.58 with 4.43 Mhz xtal, and chroma locks OK, so I don't think I am being (too) crazy with hope of converting...