Flex 8600 CW Latency (Return to Receive)

Rich - N5ZC

I've noticed on my 8600 that there is a latency to return to receive while operating cw. I don't recall having this issue with my 6600. I'm hoping there is a setting that I'm forgetting about.

When I'm done transmitting, I can hear a relay in the rig click which I'm assuming is the T/R relay. It takes a few milliseconds for the the receive audio to reappear. I don't have a way to measure the latency, but it's significant enough that I miss the beginning portion of a call sign or exchange and have to ask for a repeat.

I tried resolving the issue with the latency setting under the filters tab. Unfortunately I can resolve the return to receive latency but then the filters are useless as I'm hearing all kinds of signals a few KHZ either side of my receive frequency.

This is not a big deal for chasing DX, but it is a significant issue during contest operations.

Am I missing a setting?

Rich - N5ZC

KD0RC

Hi Rich, what do you have CW Delay set to? This is the Delay on the control panel when you are in CW mode.

Gord-VA7GP

In my head, I re-name "CW Delay" to "Hangtime" to correlate with the functionality and terminology I'm more-accustomed to using for almost a half-century.

I wonder if Len is right, and changing CW Delay may give you the rapid-response you seek? And for clarity, I wonder if you might think of it as "Hangtime": semi break-in?

Rich - N5ZC

No matter the delay, there is latency (hang time) before I can hear the receiver.

During a contest I'll set the delay to 50, for normal DX chasing its in the 350 to 450 range. I've even tried a delay time of 0.

Rich - N5ZC

KD0RC

Hi Rich, do you have an amp, noise canceller or something else in line that could be causing the delay?

Rich - N5ZC

Len,

8600/PGXL/TGXL to a Antenna Genius antenna switch.

Rich - N5ZC

KD0RC

Maybe try it with just the rig into a dummy load to see if it is the rig or one of the other components.

TIM3Kmart

I just put my new 8600 & Maestro in the CQ WPX CW contest for 30 minutes. First use of CW. Break-In delay set to barely enough to prevent PTT dropping between characters at 30 wpm. I experienced exactly the same issue N5ZC reported when he started this thread. AFTER the PTT releases, there is approx. 400 ms of dead space before receive audio returns. This causes me to miss the first character sent by callers. Obviously, this delay makes the rig useless for CW contesting.

This same issue occurs when CW PTT is first engaged to transmit. The receive audio is so delayed that it comes out the speaker for approx. 400 ms AFTER the PTT has been engaged and CW is being transmitted. This causes receive audio and CW transmit monitor audio to come out of the speaker at the same time!

The 2 issues tell me 1 obvious thing. The rig has EXCESSIVE receive processing time (time for RF being received to audio be sent to speaker). Given all the processing horsepower in the rig, this is most unexpected. Something is amiss. A software bug? An operation detail of which I am not aware? I don't know.

Note: This is not a remote latency issue. Everything is on a switch just 10' away. Network stats are "Excellent".

Anyone know if Flex has acknowledged this issue and provided guidance or a solution?

Tim, AB0S

KD0RC

Hi Tim, are you listening to speakers or headphones plugged into the back of the radio, or are you listening to PC Audio?

km9r.mike

Hi Tim,

The only thing close to what you have described, and I believe FRS is aware, is the following. In my cw panel, cw delay is always set to minimum or zero, HOWEVER, for whatever unknown reason if I engage my 8600's internal ATU and have it do a tune cycle ( in memory mode or not) the cw delay remains at zero until I transmit in cw and then an unwanted delay of 241 ms is added. As long as the internal ATU is active that is my new minimum delay and just like you describe receive will not recover until that delay has passed. When I put the internal ATU in bypass mode, the delay of 241 ms remains until I transmit again in cw and the delay will return back to my desired 0 ms. At 0 ms delay the receiver recovers immediately. Since you like to do sprints as well, you know this feature is even more important for sprints. I do not know if you were using your 8600's internal ATU during WPX. If so it could have been adding more delay than you desired. I think Rich was not using his internal ATU , but I am not certain about that. At zero MS delay the radio has zero issues with the receive recovering or engaging properly due to a perceived processing issue. If there is a 400 ms delay set in the cw control panel window, then the receive will engage after 400ms every time. If you were not using your 8600's internal ATU then I do not know what is causing your delay issue. I use an external tuner to avoid this unwanted added delay until the issue is fixed. Currently using SSDR v3.8.23. One more thing I need to add. An unwanted delay of 241 ms is only added when cw speed in the cw control window is set to the minimum of 5 wpm. At 100 wpm the unwanted added delay is 13ms. If cw speed was set at 5 wpm and instead of a 0 ms delay set by me, say I had 10ms set, the unwanted delay caused by the internal ATU would still be 241ms and not 241 + 10 or 251ms. Like I said I prefer a delay of 0 ms so I use an external tuner for now.

73 mike km9r