Thanks guys for input. Will see if I can keep the RF out. > On Feb 8, 2021, at 3:58 PM, Jim Brown <k...@audiosystemsgroup.com> wrote: > > On 2/8/2021 4:19 PM, JOE MIXSELL wrote: >> Wonder if anyone has seen this behavior and if so what might you have done >> to eliminate it. Set up is TS 590, MFJ 1204 and HP labtop. Cabling supplied >> by MFJ with the 1204 unit. Antenna is ground mounted vertical about 35 to >> 40 feet from shack. For a power out level of 25 watts or less the >> transmitter seems to function normally but at a higher level the output from >> the transmitter is irregular, varying rather than a steady output level. >> I'm believing that there is some RFI susceptibility in the 1204 itself or >> the cabling. Has anyone seen something similar and if so what did you do to >> eliminate the problem. > > Lots of study material on my website about curing RFI. First, study this one > about bonding, and do it in your station. > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fk9yc.com%2FGroundingAndAudio.pdf&data=04%7C01%7C%7Ccc97d2c6a7cc44bc12fa08d8cc95e1b6%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637484291389463009%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=niyTHmVNg6jhJW5ECcVdqOJzh1naD%2FctVKkKMyEzFJg%3D&reserved=0 > > Second, use ferrites on cables connecting equipment in your shack as > described in this tutorial on killing RF noise. The document is geared to > killing RX noise, but the same Laws of Physics apply to receiving > interference. > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fk9yc.com%2FKillingReceiveNoise.pdf&data=04%7C01%7C%7Ccc97d2c6a7cc44bc12fa08d8cc95e1b6%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637484291389463009%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=6dACmGb0ajSOHyDY%2BUg9ugIk9A4EtnZwlox%2BF7%2FJ7Io%3D&reserved=0 > > Third, look at your vertical. Is it one that requires radials? Does it have > resonant radials for every band? If it doesn't, or if it doesn't have enough, > the vertical will use your coax shield as a radial, putting RF in your shack. > > And finally, use this Cookbook to build a common mode choke to be installed > at the base of the vertical. This will keep RF off of the coax. > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fk9yc.com%2F2018Cookbook.pdf&data=04%7C01%7C%7Ccc97d2c6a7cc44bc12fa08d8cc95e1b6%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637484291389463009%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=gTqemJsVFrHhKQrLgXhkoOIz%2BRWCARPh9JFNhVNsuoY%3D&reserved=0 > > 73, Jim K9YC > > > _______________________________________________ > wsjt-devel mailing list > wsjt-devel@lists.sourceforge.net > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.sourceforge.net%2Flists%2Flistinfo%2Fwsjt-devel&data=04%7C01%7C%7Ccc97d2c6a7cc44bc12fa08d8cc95e1b6%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637484291389463009%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=dnqs%2BsB3M9T7VMSC0Qr91o7E%2BGVVFxGm%2FKx6fikA1wY%3D&reserved=0
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