Squeal/noise when activating PTT at Radio Site

[Serge_VA3SB]

Hello to the group.

I have been experiencing an issue for quite some time while trying to operate SSB.
I operate a pair of RemoteRig boxes with a K3s/KPA500/KAT500 at my remote station site. I operate a K3/0 on the control side (city). Not a high powered station but it does play well and I have fun. SInce we are not into the third phase of the pandemic I thought of operating more SSB contests from the stations as I am primarily a cw/rtty operator.

The issue I have been wrestling with is that whenever I activate the remote K3s from my control K3/0 for SSB, I experience a "squeal/noise" whether I have audio or not. I have attached a sound file for your info recorded yesterday. I have another receiver at the site and use it along with RemoteHam software to record the output of my K3s station. This recording is of me only hitting my foot switch PTT three times without transmitting any audio. This was recorded at the 10W output level of the K3s.

I have checked and rechecked my settings and jumpers in the RRC control side box, I will be checking the red straps in the Radio Side RRC as well as the power supply (Thank you Mitch, K7DX) when I next get a chance to visit the remote station. I have also made sure that the settings are consistent with what the K3s manual indicates for Mic gain as well as compression but have not been able to find a solution. I am using a Heil  Pro 7 headset and the problem is still there if I connect it directly to the K3/0 without connection to the shack computer. As the recording indicates, the problem is there irrespective of whether there is audio or not. I get the problem whether I use the amplifier (500 Watts) or barefoot even at the 5 – 25 watt levels. The intensity does not appear to change at all with power level.

 The squeal/background noise is so bad that I cannot operate as folks tell me that it is very bad and interferes with my voice. I have checked the various lists and carried out 100's of google searches without success. 

I would be glad to share any settings/config files/other info that you think could be helpful in troubleshooting this issue.

I would greatly appreciate any help/guidance/advice that the group could provide.

Thank you in advance and have a wonderful weekend everyone.

Serge
VA3SB

[sm2o]

Hi

I would guess it's due to missplaced or broken red straps. Also it's better to connect the mic direct to the Control-RRC not to the the K3/0-Mini as it add a little noise.

73 de mike

[Serge_VA3SB]

Good morning Mike. Thank you for your response.
I have already checked my red strap on my Control Unit RRC and plan to check my Radio  Unit RRC when I next visit the remote site.
I am curious about the comment you made regarding connecting the Mic directly to the Control RRC and not to the K3/0 Mini. I am presently using the Elecraft cable assembly to connect the K3/) Mini to the RRC Control unit. How would I connect the Mic directly to the RRC in this case?

Thank you in advance.

Regards

Serge
VA3SB

[Serge_VA3SB]

Good morning everyone. Further to my earlier post, I received some very helpful feedback from Mitch K7DX, Will WC2L, Gerry W1VE and Mike SM2O on this issue.

I travelled up to the remote site and confirmed the settings of the red straps in the Radio RRC, I then removed all the connections from the RRC to the Radio, re-seated all connectors and added a couple of additional ferrites on some of the cables.

In doing the above work, I seem to have resolved the issue. No sure specifically what it was but it appears that it was something related to the connections either to the RRC or the Radio and not related to any of the RRC or K3s settings.

Thanks again to all for your assistance.

Have a great day and be safe.

73

Serge
VA3SB