Hi,   I have a HP 54501A 100MHz digitizing o’scope   Two  probes (notoriginal)   1ea  HP 54501ADigitizing O’scop Front panel Operation Reference   1ea  HP 54501ADigitizing O’scope Programming Reference   Screen is razor sharp. When first turned on a message shows in small type “cal ram checksumerror. Re-cal instrument”.  When thedigital dial is rotated, it disappears. I’m selling this as I will be moving inthe spring.   $240  plus shippingfrom 92220.   If interested please send me an ORIGINAL email because ifyou use the hyperlink on the address Yahoophoey will stack it up with otheremails which becomes a PITA to sort out.   Regards,   Perrier