Hello Mickle,   many thanks for these documents!   Do you know, whether Datron 1271, 1281 are identical in hardware, and Fluke 8508A very similar to the Datron instruments, concerning the main PCB? Maybe differences between 8508 and 1281, only concerning volt references and user inetrface?   Frank --- Alle Postfächer an einem Ort Jetzt wechseln und E-Mail-Adresse mitnehmen! Rundum glücklich mit freenetMail