Agilent / Keysight 6000A series - modern passive scope probes - Page 1
Forum section: electronics / testgear

author: zitt
author_rank: Regular Contributor
timestamp: April 12, 2018, 05:22:24 am
content: Can anyone offer advice on a modern passive probe to work with the 6000A series scopes?I'm thinking of buying one used without any accessories with 500MHz of bandwidth; but am kinda disappointed in the current Keysight design: N2843AI like the older probes which came with the 54832D scopes:1165A which had the easy click aritcheture but they seemed to go away from these in modern designs.Am I mistaken? Are they all "knob" based passive probes now?Can I use a 1165A as-is without issue on the 6000A series scopes?

author: Berni
author_rank: Super Contributor
timestamp: April 12, 2018, 05:40:24 am
content: I have such probes and they work just fine on my MSO6000. I like these more than the modern ones because in comparison they are a lot smaller and the cable is much more flexible while not being stubborn and coiling up the way it wants to.As far as i know there are still no electronics inside them so it detects it via a resistor on that ring pin just like all other passive 10x probes. In theory they work even on non Keysight scopes if it could physically fit on there, tho the probe auto detection wouldn't work.Where you have to watch it with old probes is when they are active ones. The old scopes used to be able to adjust the low voltage supply rail on the probe connector between 3 to 6V. A lot of non high end scopes (Such as the 6000 series) are missing this circuitry and will always provide only 3V. A lot of the newer active probes need 3V so they work fine but older probes need more. The scope is smart enough to know what probes it can work with by reading a little EEPROM inside and will refuse to work with those probes (But there are ways of making it work).

author: TheSteve
author_rank: Unknown
timestamp: April 12, 2018, 06:01:21 am
content: 1165A/1161A etc are the best passive probes HPAK ever made. Finding complete sets for a good deal on ebay takes time but is totally worth it. Forget the newer probes and buy them for your 6000A. I use them with my MSOX3000 series scope.

author: zitt
author_rank: Regular Contributor
timestamp: April 12, 2018, 04:51:45 pm
content: Thanks, great to hear. I'm looking for some 1165As.Does anyone know if the 1153A Diff Probe will work with the 6000A series?I bought one but the scope I had purchased had to be returned to seller for Infant mortality.

author: Keysight DanielBogdanoff
author_rank: Unknown
timestamp: April 12, 2018, 05:42:33 pm
content: In general, all passive probes are going to work with a 6000A. The little pin that connects to the scope is just an ID resistor to automatically set the scope to the right probe attenuation ratio. If you have trouble with a certain passive probe, you can always just pull that pin out with a pair of pliers and set the attenuation ratio manually.The 1153A is NOT compatible with the 6000A scopes.However, my comment on this thread discussing 1152A probes may be applicable. I haven't confirmed, though.https://www.eevblog.com/forum/testgear/agilent-mso-500060007000-anyone-hacked-these-scopes/400/The 1152A's needed +-4V, and the 1153A needs +-6V to operate.

author: Berni
author_rank: Super Contributor
timestamp: April 12, 2018, 06:09:19 pm
content: My trick of getting around that detection pin is to put some tape over it so that it doesn't make contact.I have tested my 1152A probes on a MSO6000 and MSOX3000, both work with the tape over middle pin trick. However the performance of the probe is degraded in that the signal from the probe gets clipped at high amplitudes and also you loose the DC offset removal feature. For looking at 3.3V logic signals it still has enough voltage swing so its still pretty usable.I have a 1153A too but i only used that probe on my MSO9000 (that officially supports this probe) so i have no idea how much the performance on it degrades when forced to work on the incompatible scope.

author: MarkL
author_rank: Unknown
timestamp: April 12, 2018, 07:06:29 pm
content: Quote from: zitt on April 12, 2018, 05:22:24 amI found them disappointing also. I have four N2890A, the predecessor of the N2843A. They are really unsuitable for gentle and careful probing on dense boards. They don't exactly exude the usual HP/Agilent/Keysight quality.I replaced them with N2894A which is a 2.5mm probe (half the diameter). It has a replaceable pogo tip (and just the tip, not the whole cartridge), and you can get a boatload of different 2.5mm accessories depending on your probing needs. The cable is thinner and more flexible, but is still a little stiffer than some older probes I have from Tek, and I'm guessing the older 1165A.I believe the N2894A and others in the N2870A 2.5mm series are made by PMK (http://pmk.de), if you want to look for some of those at less cost.For active probes, the N2744A TekProbe adapter works well and is listed as supported on the 6000. It's a bit pricey, but can open the door to some great bargains on used Tek active probes.

author: zitt
author_rank: Regular Contributor
timestamp: April 12, 2018, 07:42:38 pm
content: Quote from: Keysight DanielBogdanoff on April 12, 2018, 05:42:33 pmGreat info; thanks.I saw your posts in that thread; but there was a lot of noise about other things as it was off topic in that thread.FYI: I bought the 6104A from Keysight (Malaysia - Fleabay) earlier today - so in some way Keysight is getting some money from me.Quote from: Berni on April 12, 2018, 06:09:19 pmGood to know. My real reason for purchasing the 1153A was to measure current across a sense resistor on the power rails of a Pinball Sound Card. I didn't want there to be a "scope" vs "pinball machine" ground reference issue since the only way to measure the rails is via a high-side sense resistor (too many paths to ground in this design).Quote from: MarkL on April 12, 2018, 07:06:29 pmGood to know. I'm trying to avoid manual twist type bnc connectors. Not sure why; but I like the idea of the spring loaded bnc which you just push on. I think the "higher tech" easy connect of the 1165As makes me feel like I'm using a modern, bleeding edge scope even tho the 6000A series is almost 10yrs old now.Quote from: MarkL on April 12, 2018, 07:06:29 pmOutside the Diff probe (1163A); I don't have any Active probe immediate needs.Lowercost is def a positive. So far I've only acquired one 1165A from Fleabay. I'd like to get a full set of 4 qty 1165As and maybe an active probe; however, my credit card will need some time to recover from the 6104A purchase.If you have some lowcost Tek probe suggestions; I'm certainly interested in the research value.

author: MarkL
author_rank: Unknown
timestamp: April 12, 2018, 09:29:37 pm
content: Quote from: zitt on April 12, 2018, 07:42:38 pmBest of luck to you on the set of 1165As.Some of the better deals on Tek probes are the single-ended 1GHz P6243 and 1.5GHz P6245. With some patience, they can be had for around $100 or less on ebay. I would get ones marked as 40V pk-pk max (later ones are 15V pk-pk). And I wouldn't buy them "As-is/Parts" because if the front-end in the tip is blown up, they are unrepairable.Other useful probes that come up from time to time are the P6247 1GHz and P6248 1.7GHz differential probe, P5205 HV differential probe, and TCP202 current probe.The N2744A adapter supports 15 or 20 different Tek probes, so what you consider a bargain depends on what you want to do and what HP/Agilent/Keysight options exist that can directly plug in.I like the Tek probes because you can also use them standalone on any equipment if you get a Tek 1103 probe power supply. It's just not as convenient as the N2744A adapter when using them with an Agilent/Keysight scope.

author: Berni
author_rank: Super Contributor
timestamp: April 13, 2018, 05:18:04 am
content: I say give the 1153A a try with the tape over middle pin trick and feed it from a signal generator first to see how well it works when running with too little voltage. You probably also have to test how high in common mode they can go too since that might be reduced. But i wouldn't expect the frequency response to be affected much at all.As for the 1152A, its a neat probe to pick up since they can sell for $100 on ebay and it works really well for probing digital circuitry. When using a passive probe that crocodile clip ground lead starts to ring and distort anything above 10MHz while using the little ground spring can be anoying. Due to the low input capacitance of the 1152A (I think about 0.7pF) there is so little return current trough the ground lead that you can have a 30cm(a foot) ground wire from the probe and even a 50MHz digital signal looks great and sharp. You still need the tiny ground spring to get the designed 2.5GHz out of it but not many have a scope that does 2.5GHz anyway.