[arm-allstar] Obnoxious tone

David McGough kb4fxc at inttek.net
Sat Jun 19 17:36:37 EDT 2021


Hi Bryan,

Okay, your scenario is the opposite from what I was thinking in my first 
posting---the whine is on the TX audio, as transmitted by the Alinco; not 
on the RX audio received by the Alinco.

So, the test I previously described won't really tell us anything, there
isn't a reason to try that. This situation could indeed be caused by RF
from the Alinco transmitter getting back into the RIM-alinco audio.

I'm pondering how to some perform tests and try to isolate where there the 
issue is....An obvious thing to try would be to run the Alinco into a 
dummy load (as previously suggested by Scott) and see if the problem just 
disappears.  If it does go away, at least you know where to focus your 
efforts.

73, David KB4FXC


On Sat, 19 Jun 2021, Bryan Johnson wrote:

> Hi David,
> 
> I should have said it is on Allstar audio being transmitted from the 
> Alinco. So I hear it when listening on my HT or mobile (not when using 
> an app like Echolink or dvs mobile to connect to the node), both on my 
> repeater and when using reverse pair setting to listen directly to the 
> Alinco.
> 
> I have not tried removing the RIM and transmitting with the Alinco to 
> make sure the noise is no longer present, but I suspect it is only 
> occurring with the RIM attached. I will go out and try it when/if it 
> cools down later (over 110 here today).
> 
> Thanks, Bryan - K6RBJ
> 
> On 6/19/2021 2:10 PM, David McGough wrote:
> > Bryan,
> >
> > Several users have reported strange behavior recently with RIM adapters,
> > I'm beginning to wonder if there is a pattern?
> >
> > Since you're reporting this on the AllStar RX audio, not TX audio, it's
> > unlikely that this is caused by an RF source.
> >
> > Does the whine go away if you unplug the RIM-Alinco from the radio?  To
> > get AllStar to see COS and "key," you may need to go into
> > simpleusb-tune-menu, option 'J', and change the telemetry setting from 2
> > (usb) to 3 (usbinvert), or vice-versa, to get AllStar to "key."  ....This
> > is a temporary change for testing, of course.
> >
> > Also, try leaving the RIM-Alinco attached to the radio, but turn the radio
> > off. Again, you may have to adjust simpleusb-tune-menu option 'J'
> > temporarily.
> >
> >
> > 73, David KB4FXC
> >
> >
> >
> > On Sat, 19 Jun 2021, "Bryan Johnson via ARM-allstar" wrote:
> >
> >> I have a server with the latest hamvoip version (pre-release from a
> >> couple weeks ago) installed. I'm using simpleusb and a RIM-Alinco tied
> >> to a newer DR-135. I get a very obnoxious whine (around a 1000khz or so)
> >> on received audio (audio coming from the allstar server, that is) from
> >> the Alinco. I've got ferrite beads on the power wires (Alinco and usb
> >> cable feeding the pi), ethernet cable and usb cable from the pi to the
> >> RIM-Alinco. I tried another power supply for the pi (3b+). I even tried
> >> a 12 volt to usb converter (off the same 12 vdc supply powering the
> >> Alinco) to power the pi. Tried disconnecting the ethernet cable to
> >> eliminate suspects. Still can't figure out where the whine is coming
> >> from, but I suspect the RIM-Alinco. Anyone else run across this issue?
> >> And suggestions to get rid of the whine? Wondering if I could use a
> >> straight thru DB9 cable to move the RIM-Alinco away from the back of the
> >> DR-135 to see if that helps (assuming some sort of RF feedback from the
> >> Alinco). It has me stumped.
> >>
> >> Thanks,
> >>
> >> Bryan - K6RBJ
> >>
> >> _______________________________________________
> >>
> >> ARM-allstar mailing list
> >> ARM-allstar at hamvoip.org
> >> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
> >>
> >> Visit the BBB and RPi2/3/4 web page - http://hamvoip.org
> >>
> 



More information about the ARM-allstar mailing list