Flex 6500 transmitting popping sound

Bob KN4HH

This morning, I checked into my local AM net and I was told that a continuous popping noise was heard in my audio. I tried SSB and received the same report. I then disconnected the microphone and the popping can still be heard. I disconnected all peripherals leaving only DC power, LAN connection, and RF cable. The popping can still be **** the carrier. I disconnected the antenna and transmitted into a dummy load and the popping is still present. I watched the transmit waveform on the SmartSDR display. When I transmitted, I noticed that the popping was present on the baseline and did not affect the carrier itself as if the popping was a form of modulation. I tried all bands and all transmit modes with the same result.

I performed a complete factory reset and nothing changed.

Any suggestions would be appreciated.

Alan

Bob

On the Node-Red Ham Radio group, we found if we send a command to the Flex API with a Carriage Return/Line Feed included in the command, the Flex Server seemed to halt sending the VITA 49 packets, for a brief moment. This "halt" created an obvious, interruption and "popping" in the TX stream. It would be very pronounced on AM, since the carrier would be interrupted.

Some reported the same observation with third-party applications that use TCP to command the Flex.

As a next step to investigate the source of popping, stop all of your third party applications, check for popping. If none, you found the problem.

Then, restart each third-party application, one at a time, check for popping until you find the culprit.

Alan

WA9WUD

David Decoons, wo2x

I have emailed Bob the updated VITA49 and FlexRadio flows. This should eliminate his popping due to Node Red.

Other programs and apps that send TCP commands via API can also have the same effect if sending commands while the radio is transmitting.

Dave wo2x

Alan

oh......Bob.....I did not remember we loaded Node-Red for you.

Looks like you and Dave have the fix in hand.

Alan

Bob KN4HH

Thanks, Dave and Alan. Yes updated VITA49 and FlexRadio flows cured the problem.

73, Bob, KN4HH

David Decoons, wo2x

Good to hear!!

I am working on some more enhancements to the FlexRadio flow to allow auto detecting of radio model and software version then set meter numbers appropriately.

73

Dave wo2x