Frequently asked questions on the eoSense instrument

The purpose of these Frequently Asked Questions (FAQs) is to answer most of questions in order to help you to better understand the measuring performances and advantages of using Kapteos technologies inside the applications.

FAQS on eoSense instrument

General frequently asked technical questions

The main question to ask yourself is the frequency bandwidth of the electric field to be measured.
To date, 7 choices of instruments are available:

  • 40 Hz to 30 MHz (eoSense LF-30S)
  • 1 kHz to 1 GHz (eoSense MF-01U)
  • 100 kHz to 10 GHz (eoSense HF-10)
  • 10 kHz to 10 GHz (eoSense HF-10V)
  • 100 kHz to 20 GHz (eoSense HF-20)
  • 10 kHz to 20 GHz (eoSense HF-20V)
  • 20 kHz to 40 GHz (eoSense HF-40)

Whichever version of the chosen instrument, the probe will work on any of the instrument (after calibration at Kapteos).

Before an eventual purchase, Kapteos offers 3 possibilities of service:

  • A theoretical approach based on a simulation software
  • The rental of an equipment
  • The measurements made by Kapteos in your application (in your premises or in an already installed application)

If the required document is not available on our website, please contact your local supplier or Kapteos by email at, or by telephone at +33 (0)4 79 62 88 34 from Monday to Friday from 9:00 to 12:00 a.m. and 2:00 p.m. to 5:00 p.m.

The instrument is routinely calibrated on delivery. A calibration certificate is supplied with the unit. This certificate is valid for 2 years. It is strongly recommended that a calibration renewal request is applied at least 2 months before the expiry date as the renewal procedure requires the return of the equipment at Kapteos and involves a complex tooling.
In no event, the calibration is done by the customer or by Kapteos at the customer’s plant.

At maximum, the eoSense instrument can measure 3 channels, so 3 probes (one channel = one probe). If you need to connect more than 3 probes, Kapteos proposes eoSwitch. This accessory (under development) enables up to 48 probes to be connected to a single eoSense instrument.

No because of the calibration procedure. A probe must be always connected to the same input channel. On top of that, the real-time antenna factor correction involves to have always the same probe at the same input channel.

A user guide shows all the conditions of use of the instrument and particularly thermal conditions which must be between 15 and 30 °C. The maximum and minimum temperatures must be respected because they strongly affect the correct functioning of the system.

This is a very important point in the operation of the eoSense instrument.
As a matter of fact, the antenna factor enables:

  • To calculate in real time the absolute value of the electric field
  • To correct in real time all the errors due to the measurement chain (from the probe to the instrument output) due to the environment of the measurement (temperature, humidity …). This correction also takes into account almost all the frequency band to be measured and not a single frequency.

With this performing system, the eoSense instrument allows the electric field measurement outside a laboratory temperature-regulated room and thus make extremely repetitive field measurements.
This antenna factor is available through an analogue electrical signal for each channel of the device.

To go technically further in the antenna factor/normalisation factor

The E-field is calculated as follows: E (V/m) = E ref / NF * V out with

  • E (V/m) = measured electric field in volts per meter (V/m)
  • E ref = the calibration value of the eoSense instrument related to the concerned channel (one E ref per channel)
  • V out = voltage available on the bottom channel connector of eoSense which is connected to your instrument (oscilloscope, VNA, spectrum analyser…). This voltage is an analog value always present and is a proportional value to the measured electric field.
  • NF out = voltage available on the upper channel BNC connector of eoSense. This voltage is an analog value always present and is related (for each channel) of the losses, drifts, frequencies….

So, to measure an electric field in V/m, you have to:

  • Connect V out (bottom output connector of eoSense) to your instrument to channel 1 for exemple
  • Connect NF out (upper output BNC connector of eoSense) to your instrument to channel 2 for exemple
  • Apply the above formula

If you do not have enough inputs on your instrument (oscilloscope for exemple), you may follow the following steps:

  • Connect V out (bottom output connector of eoSense) to your instrument to channel 1 for exemple
  • Perform the measurement
  • Export the antenna factor (AF) values (values shown on the main software window) of eoSense
  • Synchronise (with the time) the file from the measured values V out with the exported file from eoSense
  • Apply the following formula E (V/m) = AF * V out

The following elements are available for sale:

  • Accessories
    • eoSwitch to connect from 4 up to 48 probes onto an eoSense instrument
    • eoP-EXT to extend the fibre optic length between the instrument and the probe
    • eoAcq to record the measured signal (for eoSense LF version)
  • In option, the eoSense instrument can integrate:
    • AMP: to amplify the analogue output of eoSense and thus increase the minimum measurable E-field (for eoSense MF and HF versions)

For further information on these items, please contact Kapteos by email at, or by telephone at +33 (0)4 79 62 88 34 from Monday to Friday from 9:00 to 12:00 a.m. and 2:00 p.m. to 5:00 p.m.

When Kapteos develops a new software version of the instrument, this one is sent by email to the customer.
A PDF installation guide is provided to help you in the few installation steps.

Yes. This 2-hour training is a free service. This can be done remotely (with Skype or similar) or at the customer’s plant thanks to the user friendly control software of the eoSense instrument.

For customers who want to maximize the measuring performances of probes, Kapteos offers on-demand trainings at the customer’s plant in order to understand all the possibilities offered by the many features of the eoSense instrument.

For further information on these trainings, please contact Kapteos by email at, or by telephone at +33 (0)4 79 62 88 34 from Monday to Friday from 9:00 to 12:00 a.m. and 2:00 p.m. to 5:00 p.m.