Support & FAQs

Have a Question or need technical support?

If you have any questions about our noise cancelling products or require some support please don’t hesitate to contact us.  Also, have a look at bhi's most commonly asked questions as they may help you...

Q. What does the fourth DIP switch on the NES10-2MKII do on the back of the speaker?
A. Nothing, it is not used.

Q. Do bhi DSP noise cancelling products work with SSB transmissions?
A. Yes they work with SSB transmissions and on all other radio bands as the DSP noise cancelling works with any signal that contains speech and is able to differentiate the speech from the noise.

Q. What adjustments do I need to make during use on the NES10-2MK3?.
A. The Volume/sensitivity control on the top of the speaker should be set at a qtr turn up from minimum.  You can make fine adjustments to this depending on the volume of the normal listening level from your radio in bypass mode. Once the NES10-2 is configured to your own personal settings the only adjustments needed are to select the suitable filter level for the current operating conditions (see user guide for details).

Q. I can sometimes hear a beating sound when listening to the unit?
A.  If you listen to bhi DSP noise cancelling products with no audio signal present, you may hear some DSP processing noise.  This is normal and part of the DSP doing its work.  Once a noisy signal is present you should not be able to hear this noise when listening. 

Q. Can I use a switch mode power supply with the speakers and in-line units?.
A. Yes you can use a switched mode power supply, but just be aware that the cheaper lower cost switched mode power supplies have been known to generate noise and cause interference.

Q. When transmitting, the signal can be heard through the speaker on the radio or in my headphones.
Explanation: bhi DSP noise cancelling products have plenty of RF protection inside and are not causing the issue. The two main reasons are: a) A poorly matched antenna which results in RF being reflected back into the radio room.  b)  A difference in Ground currents between pieces of equipment.  Firstly check that all your coax connections are secure, and that your antenna system is matched up as best it can be at the antenna feed point.  Also make sure that all your cables are routed as far away from the RF as possible. Having an Elevated SWR on the coax leading to your transceiver can cause transmit audio to be present. Try to match your antenna system up at the antenna feed point, and you shouldn’t hear any audio on transmit.  If this is not possible due to your setup and location then the following should help in eliminating this issue.
A1. Try using on a separate DC power supply to power your bhi unit.  We sell a number of different power supplies to suit our various DSP noise cancelling products: bhi power supplies
A2. Use one of our new bhi GroundBreaker audio isolation units to get rid of the feedback.  This new audio product totally isolates the grounds of your ancillary equipment from those of the radio system.  It is easy to install and simply plugs in between your radio and ancillary audio equipment.  There are a number of versions to suit most connections and impedances.  Check out the bhi website for more information. https://www.bhi-ltd.com/noise-cancelling/accessories/groundbreaker.html
A3. Look at both help sheets below for a solution.

Additional Help

bhi have published the following documents to answer any further questions you may have.

RF Breakthrough/Earth Loop FAQ

RF breakthrough Help Sheet 1
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RF breakthrough - power supply Help Sheet 2