[Elecraft] USB Noise core gets hot when operating FT*?

[AE4PB at carolinaheli.com]

Thanks Rick, 

     My Antenna situation is temporary. I purchased a Hustler 6BTV from DX
Engineering am working on getting it installed. It may take several weeks as
I work full time and  am working towards my MBA full time. I may shuffle the
project priorities around and work on the Coax routing to move my temporary
antenna outdoors. Since it's a temporary setup I'll be routing out through
the window which is going to take a bit of construction to achieve something
that's secure and energy friendly. I'm not able to avoid using USB but I can
certainly move the antenna. 

 

Jerry Moore

AE4PB

 

>Jerry,

 

>Ignoring how you've set up your station for the moment (every station has
compromises but some push that to an extreme); the shutdown? of the
connection is likely that RF got into the USB cable (as demonstrated by the
hot >ferrite) which caused the USB port hardware to lock up.

 

>USB hardware can 'stick' so it won't work properly, a complete power cycle
empties it of any charge, 'unsticking' the hardware.? (Yah a gross
simplification, but you get the point.)

 

>The only SURE way to restore it to function (assuming it's not blown) is a
complete power down (unplugged from all power, let the power supply drain,
disconnect the laptop battery, count another ten seconds) and restart.? That
is >why it worked after you 'cooled it off'.

 

>If you can shift to a real serial port (not a serial dongle), that will
help.? USB is RF intolerant compared to serial.? It's simplest to avoid USB
as much as feasible near any RF.

 

>If you can't avoid USB, you'll need to add a lot more ferrite or better
yet, improve the antenna situation dramatically.

 

>In the cases I MUST run a USB connection, I distance the antenna from the
computer as much as possible and I run <100 watts (QRP to me), but generally
that's when I run a portable station.? Jim, K9YC will tell you it's related
to 'Pin >1' and the short version is that is has to do with bonding all
things to a common ground; USB devices often ignore this.

 

>In a few cases, improved bonding between the computer and radio /may/ help,
but I'd have low hopes if the antenna is mere feet away.? Take the hot
ferrite as a warning sign, it's not a healthy environment.

 

>73,

>Rick NK7I