Probemaster 4232 Differential Probe for Audio Measurments / BTL Amplifiers

[Farley]

I would be interested in hearing of anyone's experience with the Probemaster 4232 Differential Probe (http://probemaster.com/4232-differential-probe-1-10-100-25-mhz-1400v/). I'm considering it for measurements of BTL / Class D audio amplifiers.
This particular model appears to be available under different brand names.

[saturation]

Yes, its a rebrand for Testec? Sapphire SI 9001 as the OEM.

I prefer the older design Pintek DP 25 which does the same thing and is cheaper.  They have similar specs.  I think both have been reviewed on the forum in the past as well as tear downs.

The main advantage of the Sapphire version is its slim profile and battery power.

What I've seen happen over time is just through daily wear and tear, the cables are damaged.  Since they are integrated into the hardware, its a bigger pain to replace.

The Pintek types uses standard probes and cables which means easy to replace and so you also have the whole breath of accessories for such.  Also stores more neatly since probes can be removed.

The Pintek is brick powered, and somehwat thicker, a design has been around for ~15+ years.

https://www.eevblog.com/forum/testgear/teardown-pintek-dp-25-differentail-probe/

Sapphire teardown:

https://www.eevblog.com/forum/blog/eevblog-932-how-does-a-hv-differential-probe-work/

[Farley]

Thanks saturation for the detailed response.

After reading the links you provided it appears the Pintek DP-25 should be more than suitable for my intended use.

I like the removable probes on the Pintek.  Having the power brick for power is OK with me except that it appears from reading the links you provided that Pintek have reversed the polarity on the DC barrel connector, placing the positive voltage on the outside. I've seen that done before. I don't understand the logic behind that decision.

I haven't yet found a U.S. distributor for the Pintek. It does appear that the Rigol RP1025D is a rebranded version and is easily available here in the U.S. at almost twice the price of an original. I'm guessing Rigol has an agreement with Pintek involving distribution of their probes. I do find the Pintek listed on eBay and AliExpress though.

[saturation]

Its hard to check for the rebrands, because you don't know what brand name is for the Pintek clones.

I found AideTek US seller is a clear rebrand for as low as $180 for NJ shipment and the same from a China source, but that was last year.  This year so far price is as example:

http://www.ebay.com/itm/New-Pro-Differential-probes-DC-25Mhz-Max-Voltage-1300V-Tektronix-OEM-Taiwan-CAT3-/290711961811?hash=item43afc880d3:g:~3oAAOSwD0lUhK~W

The brick power supply, besides the polarity issue, is also another tiny con if it injects some noise into your system as the brick ages or if it fails or partially fails.  In reality, such low power bricks rarely fail and Taiwan does make better quality stuff.

You can get a nice case from Flambeau, I forget what size I used, to keep everything together for under another $20 delivered.  Either tradesman or merchant models with foam are dirt cheap and built very very well.

https://www.flambeaucases.com/index.php/site/products/cases/tradesman-cases