Tektronix backwards probe compatibility

[Parak]

Anyone happen to know if the Tek 2xxx or even TDS series passive 10x probes are generally compatible with a Tek 485? As a new owner of the 485 without proper probes, I'd like to get some that better match its capabilities, and the probes for the later scopes are definitely easier to come by..

[mazurov]

I use P6139A on Tek 475A. Works quite well.

[stratogazer]

If input impedance = 1M ohm and capacitance is around 15 pF ( most Tek probes are) the compatibility won't be an issue.

[BravoV]

P6139A probe has compensation range only from 8pF up to 12pF, so if your scope input is 15pF, its out of range.

No biggie if you're not in precision measurements.

Edit :

Some references on old Tek probes  :

http://www.reprise.com/host/tektronix/reference/voltage_probes.asp

http://www.barrytech.com/tektronix/probes/tekprobes.html

[warywolfen]

View a square wave using the probe.  If you can make it look square by tweaking the compensation cap, it's OK.  If not, and you can take the probe apart without damaging it, try putting a little (say, 5 pF ) cap in parallel with the comp. cap.  By the way, whenever using a new probe with a 'scope, the compensation should be checked, and adjusted, if necessary.