Frank,Wow a fellow TDS694C owner at last.I never get anwers when I ask about this scope.Well don't have your probe type .I got these and they work for what I use them for (up to 148 mhz.62456205Both are fet probes.About the 6158The 6158 probe is x 20. Limit is 22 v rms, low input impedance.Alas it goes to 3 ghz.So it all depends on what you intend is.The goid thing is that they where designed for this scope series.RaySent from my T-Mobile 4G LTE device------ Original message------From: fauffing via groups.ioDate: Tue, Sep 8, 2020 07:19To: [email protected];Cc: Subject:Re: [TekScopes] Tek TDS694C advice plsHave you used the P6158 probes with this scope, and if you have, what are the drawbacks of the P6158 compared to the P6249?