Direct Test Mode modulation

[Mathieu Schneider]

Can't transmit a modulated carrier for FCC testing part: nRF52832

We are writing our own firmware to support FCC testing. We have been successful at controlling the chip to:

• continuously transmit an unmodulated carrier
• change channels
• adjust power levels.

But when we try to transmit a modulated carrier, we see that the signal is periodically off for roughly 100us.

The test lab requires our product sample to continuously transmit with the carrier modulated and unmodulated. Our test firmware is based on the “Direct Test Mode” firmware provided with the EV kit.

Any ideas on keeping the transmitter on 100% with modulated data?

[FormerMember]

For regulatory testing (like FCC), the easiest is to use the radio test example in the SDK. With the radio test example, you can fully control the radio; transmit unmodulated carrier, modulated carrier, control the output power, etc.