On Mon, Nov 30, 2020 at 06:39 AM, ghnatiuk@... wrote:
What do you consider expensive?
Be careful on EBAY -? make sure probe tips are not broken.
?
I have an 8405, which came with working probes whose tips were worn/broken down.
After looking around for a while I tried ordering a set of replacement tips made by ProbeMaster, intended for their oscilloscope probes. Two sizes are available: 4981ST and 4882MT ("standard" and "micro"). The folks at ProbeMaster told me these have a 0-80 UNF thread, but didn't know if they would fit an 8405 probe.
They do, and they work. They're not identical to the original tips; the insulating bushing is of a larger diameter and it ends up snugging down against the end of the HP probe barrel rather than sliding inside. I don't think that's an issue as this probe position doesn't (I don't think) require a well-characterized transmission line impedance. The thread is a good match for the probe, and the tips seem well-made and sturdy.
At $3.75 each plus shipping, I think they're a very workable alternative to buying new-old-stock HP spares (if you can find 'em) and are more convenient than having to stick an 0-80 screw into a lathe and shave it down to a point.
ProbeMaster also makes a BNC adapter, intended to fit over the end of one of their probes and convert it to a BNC male workalike, using the probe tip as the center pin. These, alas, do not fit the 8405 probe - the diameter of the ground ring at the end of the probe is wrong. It might be possible to make some sort of shim, but I haven't done so.
