The recent topic about the THS720/THS720A encourages me to submit an issue that I've had with my THS720A for some time.
The instrument is in pristine condition, both cosmetically and technically. Unfortunately, some time ago I could not resist the temptation to "upgrade" it to a THS730A by moving a few resistors, as described somewhere on the 'net.
Basically, it sort-of worked (both bandwidth and samples/sec) but it slowly filled the error log so I restored it to its original state as a THS720A.
Since then, it has been fine except for the old entries in the error log, which I haven't been able to clear. It's ugly but not a real problem of course.
I'm wondering if the error log can be cleared independently, i.e. without calibrating first (it doesn't need any adjustments) and if so, how, and if not, is calibration of the 'scope-part i.e. leaving the DVM as-is possible and sufficient? I don't have any of the special DC voltage generators needed and I'm not looking forward to set the voltages ad hoc on a normal voltage source.
Thanks in advance for any info!
Raymond
Raymond Domp Frank