I have a Yaesu 857D, MFJ-929 Auto Tuner, SingnaLinks, and an Acer Aspire 5517 Laptop. Connecting the laptop to the SignaLinks is a USB printer cable (unshielded I believe). Connecting the SignaLinks to the 857D is a purchased control/data cable. The software I am using is WSJT for data.
My issue is a tone appearing at 831 hz, 1831 Hz, and 2831 Hz on the WSJT waterfall display. My primary frequency is 14076 KHz. So these tones are 14076.831 KHz, 14077.831 KHz and 14078.831 KHz. I do not believe these tones are being transmitted, at least I hope they are not.
When I touch the radio or the tuner the amplitude of the signals and the three tones reduces. Not much so even though my system is grounded via all the cables there might be a minor ground loop somewhere. But I don't think that is causing those three tones to appear.
If I move the connection to the PC the tones reduce greatly but are still visible. Removing the cable locks up the program (as expected). Moving the connections at the SignaLinks does nothing, so I appears to be the PC/Cable connection. Also turning off the SignaLinks does nothing. But it appears the tones are being passed along the cables between the PC and the radio. If I listen real carefully, it sounds like the tones are clocking at 2000ms.
I have applied Snap-on Ferrite beads/cores (whatever you want to call them) and this is not doing anything at all to the tones. The ferrites are on both ends of the USB cable, both ends of the control/data cable, and the PC end of the PC power cable.
Can anyone think of what might be causing the tones? I don't think it is interfering with data reception, but it seems to be more annoying than anything else. I normally keep the radio's audio volume at zero when working data.
My issue is a tone appearing at 831 hz, 1831 Hz, and 2831 Hz on the WSJT waterfall display. My primary frequency is 14076 KHz. So these tones are 14076.831 KHz, 14077.831 KHz and 14078.831 KHz. I do not believe these tones are being transmitted, at least I hope they are not.
When I touch the radio or the tuner the amplitude of the signals and the three tones reduces. Not much so even though my system is grounded via all the cables there might be a minor ground loop somewhere. But I don't think that is causing those three tones to appear.
If I move the connection to the PC the tones reduce greatly but are still visible. Removing the cable locks up the program (as expected). Moving the connections at the SignaLinks does nothing, so I appears to be the PC/Cable connection. Also turning off the SignaLinks does nothing. But it appears the tones are being passed along the cables between the PC and the radio. If I listen real carefully, it sounds like the tones are clocking at 2000ms.
I have applied Snap-on Ferrite beads/cores (whatever you want to call them) and this is not doing anything at all to the tones. The ferrites are on both ends of the USB cable, both ends of the control/data cable, and the PC end of the PC power cable.
Can anyone think of what might be causing the tones? I don't think it is interfering with data reception, but it seems to be more annoying than anything else. I normally keep the radio's audio volume at zero when working data.