Spurious PTT when using CAT on Com1 mode 7

[VA2MM]

I have been using a K3 Twin setup for a few years now and it generally works well. Lately I've been doing more CW and a long-standing issue that I have put up with on SSB is harder to live with in CW mode.

When I connect my logging program (at the control site) to the remote ratio via Com1 (USB) of the control RRC, the radio occasionally sees very short (few ms) spurious PTT and/or CW keying every few seconds. It does occur in SSB mode but it is much less obtrusive and seems less frequent on SSB than on CW where there are short bursts of on/off PTT and keying (side-tone blips). If I turn off Radio CAT control on my logging program, the problem disappears.

I do not suspect my logging software itself as the cause because this problem does not occur when directly connected to the radio, nor when connected via the radio RRC local COM1 at the radio site (I use mode-7 for COM1). 

It may be bandwidth related because PTT and keying blips occur more often if I increase the the baud rate of COM1. It is tolerable at 4800 bps but quite annoying at 38400 bps. However, the VoIP bandwidth seems fine (no audio drop-outs, except obviously during spurious PTT). COM2 is 38400 bps, per recommended K3 Twin settings.

Another (probably related) issue is that the radio sees brief spurious PTTs when I spin the VFO knob on the control end. This occurs even when I'm not using CAT control and the PTT blips stop as soon as I stop turning the VFO knob).

Currently running RRC firmware 2.9

Any ideas?

[VA2MM]

No replies? Does any else at least experience brief spurious radio PTTs when turning the VFO? My setup has always done that. Any feedback or ideas would be appreciated.

[sm2o]

There is no way Remoterig can cause the PTT to be activated by spinning the VFO. The PTT command is integrated in the audiostream to ensure the PTT to be released if the connection is broken

73 de mike

[VA2MM]

Hello Mike and thanks for the reply. As unlikely as it may seem, there are indeed brief ptt blips whenever I spin the remote VFO and this is easily reproducible on my system. This only happens via remoteRig (never locally on radio). If you are interested, I could send you a video clip of the effect.

Since PTT is exerted by the RTP audio stream, it seems to me that the radio RRC must be occasionally  receiving  a spurious RTP segment when I turn the VFO (or when there is Com1 CAT traffic), either sent as such by the control RRC, or perhaps they are serial control packets that somehow get forwarded  to an RTP port. Maybe it's a port forwarding issue on my router, but it seems strange that that should be intermittent. .

I will be traveling to the radio site this weekend and I'll take me control setup with me so I can do some tests with both RRCs on the same network to try to isolate the cause. I might try to look at the RTP stream with wire shark as I reproduce the problem.

Regard and 73

Mark VA2MM

[sm2o]

No it's impossible. Dont' wast your time on looking at that level. It' proabably much simple than that

/mike

[sm2o]

Maybe it's the same as this

Hello, I wont to upgrade you about my problem.

I have put in LAN a network packet analizer wireshark and I found that my tablet android send a UDP broadcast to port 13001

In Google I found that this is a packet send to find in the lan multicast server available

This packet received from RRC put RRC in a short PTT.

I have changed the default port on both RRC and the problem is disappeared.

I think that it is a BUG of RRC that I hope will be solved in the next firmware.

73 Maurizio