6300 + USB Hub = Hash Noise

Paul - K6HR

When I connect a USB hub to my 6300 I get heavy hash noise that obliterates parts of whatever band I'm on, and is worst on 20m. Has anyone seen this anomaly that can tell me how it was resolved? Is there a specific model of USB hub known to be "quieter" than others? Distance between the hub and radio does not appear to make any difference. The USB cables I'm connecting to the hub are the Flex FTDI cables which work quietly when connected directly to the radio. I appreciate any hints or tips you may have!

Jim Gilliam

Do you get any hash noise by using a single USB cable?

Mike va3mw

Paul

The noise is likely in the power supply and there is no model that will guarantee that it is quieter than the next, or so it seams.  It is really hit and miss at times.

A long time ago, I gave up on specific models and I started to Choke everything.  I have to admit, I can hear so much better now.  Doing this is well worth the time and effort.

This is the document that got me started down that path  http://www.yccc.org/Articles/W1HIS/CommonModeChokesW1HIS2006Apr06.pdf

I bought a case of Mix 43 and Mix 31 chokes.  It was one of the best additions I made to my station.  Choking not only affects transmitting issues, it also seriously helps with suppressing the RF like you are now hearing.  Choking a feedline at both ends really helped as well

A simple fix for you would be to try choking the power supply to the hub or trying another 5v supply on the noisy hub.

73, Mike va3mw

Bob Kozlarek

I have to agree - most of my noise emitters and birdie generators have been those infamous "wall warts". On my Verizon router I actually made my own power supply as no amount of chokes could clean it up.  The worst offender was my UPS supply which created this "swooshing" carrier that would move up and down on 75m.

W0JD

Or better still disconnect any external power from the USB hub and just depend on the 6300 to power it. The FTDI cables do not draw a lot of power.

WX7Y

another comment, some Powered USB hub's run on +12V and I always look for them and hook them up to the station power supply. Connecting them direct to the Radio really isn't a good Idea because the Radio can't power a lot of current off it's USB ports and just another unprotected path for lightning or static discharge to come into the radio's motherboard. 

I power all my Routers, Intel NUC Computer, Monitor's, Both Flex Radio's, Speakers, and Ethernet switch's off of my 13.8 Volt station Power Supply.

Having NO WALL Wort's sure keeps the noise down from those nasty cheap switching Power Supplies.

73's
Bret
WX7Y

Paul - K6HR

The hub I connected is powered by the 6300. No external power supply. I don't have an RFI problem during TX. The shack is free of RF, however as soon as I plug in this hub the noise appears immediately. In the meantime I'll try a different hub(s).

Mike va3mw

Hi Paul

I hear what you mean when you say you don't have a RF problem while transmitting.  However, other devices are using their own antennas (aka:  the power cords, etc) to radiate the noise you are hearing.

It is possible that the USB hub you have is noisy (ok, it is), but what is happening is that the RF of that noise is being radiated along other conductors (USB, power cables, etc) and that noise is making it to your antennas.  

RF in the shack means your transmitters are making it back to devices.  The RF we are talking about is other transmitters that are all over your house.  

You could try some snap on chokes on the USB cable you are using the USB hub and see if that helps at all.

Mike va3mw
 

Al K0VM

Does the HUB create RF noise when plugged into a PC ?  .. Have you tgried a different HUB from a different maker?
AL, K0VM

Ria

This is my station practice too. Switching wall warts are nasty. Some power poles and barrel connectors and you're good to go. Actually a lot of times I just snip off the wire from the wall wart and use that. you have to be careful with polarity so use a DMM to verify. 

Wayne VK4ACN

Some devices have a 5v wall wart. Whats the best way there?

Ria

If it's USB I usually connect it to a quality USB power source such as one of the Anker chargers. I haven't had much of a problem. 

Wayne VK4ACN

Thanks

Steve K9ZW

What model USB hub are you using? If you eliminated the hub and directly connect each end component are they are all free of the noise? Does choke beads on the USB cable or even just a different cable change things? 73 Steve K9ZW

Steve K9ZW

Forgot to ask if you could post some screenshots of what the noise looks like on the panadater? 73 Steve K9ZW

Paul - K6HR

Thanks to all who replied. The Anker hub in the aluminum case is working 100% noise free!