eSAP-30 is a high-performance, battery-powered active oscilloscope probe that’s both portable and packed with features. Designed for engineers, researchers, and technicians who work with RF, sensitive analog, and high-speed digital electronics. eSAP-30 bridges the critical gap between expensive, brand-locked active probes and traditional passive probes.
After a year of intensive development and over ten front-end design iterations, we’ve achieved our goal: an accessible, professional-grade tool that doesn’t compromise performance or flexibility.
With a bandwidth of 3 GHz and low input capacitance, eSAP-30 delivers precise measurements for high-speed signals such as clocks and fast transitions to ensure accurate signal integrity analysis. It’s compatible with any oscilloscope brand that provides a 50 Ω input (or a 1 MΩ input with an external attenuator). Enjoy maximum flexibility, and avoid being tied down by proprietary designs.
This probe is an essential tool in high-speed digital-system design. It enables precise measurements of high-frequency signals with minimal loading effects, making it ideal for signal integrity, jitter, and timing analysis. The low input capacitance and high input impedance make it suitable for analyzing advanced logic levels, sensitive analog circuits, and high-bandwidth data transmission standards while ensuring accurate and reliable signal fidelity.
Portability and reliability are at the core of this design. Powered by an internal battery, eSAP-30 facilitates fieldwork by eliminating the need for an external power source. It is also a reliable and well-documented tool. Each probe undergoes rigorous quality assurance, including individual functional tests and S-parameter (S21) measurements with a test report.
In the box you will find a USB charger and cable for charging the battery or updating the probe’s firmware. Be aware that the ground of the USB charger is the same ground as the input/output of the probe. A full charge will take around 10 hours with the probe ON and about six and a half hours with the probe OFF. Charging current is limited to 500 mA so eSAP-30 can be charged through any aailable USB port.
The plastic housing and tripod are 3D printed with resin. If we sell a sufficient number of probes through the campaign, we will produce a polycarbonate (PC) injection-molded housing instead, which will guarantee consistent dimensions and wall thicknesses as well as a flawless surface finish.
The internal battery is a standard 18650 lithium cell, and only four screws must be removed to replace it.
We believe in creating tools that are repairable. You should be able to maintain your probe and extend its life well after the end of its warranty period. To that end, we have sourced high-quality components from well-known manufacturers and have committed to releasing the design files at some stage. eSAP-30 is a reliable, future-proof solution for your lab and fieldwork needs.
The probe comes with several accessories. You can use the MMCX or U.FL connector directly on your DUT or use a small FR4 PCB with magnet wires. We are also including two flex PCBs that you can solder directly to your DUT. Because the FR4 and flex tips are consumable items, we’ve published their design files in our GitHub repo. The required components and approximate costs are outlined below.
The probe was not designed to be handheld and is best used in combination with the included tripod, which can be positioned at several different angles by rotating the orientation of its legs. This allows you to position the measurement point as close as possible to the DUT. You can also convert the tripod to a bipod by removing a leg.
You can leverage the flexibility of MMCX by using either the MMCX-to-U.FL cable or the MMCX-to-MMCX cable if input capacitance will not influence the load you are measuring. Or you can use the header to have less than 1 pF of input capacitance for high-frequency and low-load measurements.
eSAP-30 is already fully functional. Over the past several weeks, we’ve prototyped a number of units in-house and sent them to various testers for feedback. Their suggestions and insights on usability will help us make final adjustments before the production run.
| eSAP-30 | eSAP-30h | Tektronix TAP2500 | Tektronix TAP3500 | Siglent SAP2500 | Keysight N2796A | PICO TETRIS 2500 | |
|---|---|---|---|---|---|---|---|
| Attenuation | 10:1 | 10:1 | 10:1 | 10:1 | 10:1 | 10:1 | 10:1 |
| Output | MMCX/BNC | MMCX/BNC | TekVPI | TekVPI | SAPBus | Keysight Scope | BNC/SMA |
| Bandwidth | 3 GHz | 3 GHz | 2.5 GHz | 3.5 GHz | 2.5 GHz | 2.5 GHz | 2.5 GHz |
| Input Voltage Range | ±25 V | ±25 V | ±30 V | ±30 V | ±20 V | ±20 V | ±20 V |
| Input Impedance | 1 MΩ | 1 MΩ | 40 kΩ | 40 kΩ | 1 MΩ | 1 MΩ | 1 MΩ |
| Input Capacitance | ≤3 pF | ≤1 pF | ≤0.8 pF | ≤0.8 pF | 1.1 pF | 1 pF | 0.9 pF |
| Power Supply | 18650 battery | 18650 battery | Proprietary for scope | Proprietary for scope | Proprietary for scope | Proprietary for scope | Wall plug |
| Price | $999 | $999 | $9,217 | $12,544 | $1,998 | $3,613 | $2,235 |
We believe in longevity, transparency, and the right to repair. To that end, we are committed to releasing the design files for eSAP-30. This will include schematics, board layout files, and case design files. We designed eSAP-30 with repairability and longevity in mind. It features a standard, replaceable 18650 lithium-ion battery and easy-to-service electronics that can be accessed by removing just four screws.
We are also publishing the design files for various accessories so that our community can reproduce them or create variations that better suit their measurement applications. Our software will also be released under an open source license to enable customization and development of new features.
After the campaign ends, we will order components, including PCBs, cables, carrying cases, screws, and other accessories. (If we sell enough probes during the campaign, we will also begin production of an aluminum mold for the housing, which will likely take about two months.) To speed things up, we will begin coordinating with our partners while the campaign is still live so we can align the plastic housing, the carrying case, and the cables.
When we receive the PCB and electronic components here in Switzerland, we will begin final assembly and testing.
After our production run is complete, we will pack everything up and send it along to Crowd Supply’s fulfillment partner, Mouser Electronics, who will handle distribution to backers worldwide. You can learn more about Crowd Supply’s fulfillment service under Ordering, Paying, and Shipping in their guide.
Our biggest concern at this stage has to do with the aluminum injection mold in which we hope to invest if there is sufficient interest in eSAP-30 during the campaign. Should the manufacture and testing of this mold require several iterations, it could increase our costs and perhaps even delay fulfillment slightly.
Produced by Euler Precision in Grabs, St. Gallen, Switzerland.
Sold and shipped by Crowd Supply.
Active oscilloscope probe. Comes with carrying case, battery, charger, USB cable, input and output cables, a small box with tips, and an SMA-to-MMCX adapter.
We are a small group of passionate electronic engineers who focus on designing and delivering high-quality instruments.
