- Fully Adaptive noise cancelling with on/off switch
- Noise cancellation 9 – 35dB through 8 user selectable noise cancelling levels
- Greatly improved signal to noise ratio
- 3.5mm headphone socket
- Sturdy case with adjustable mounting bracket
- 12 – 24Vdc operation
It’s absolutely marvellous! VK stations on 20m with s2 signals at about the same level as the noise floor were perceptible but unreadable but now I can copy them 52. You just turn the box on and after a couple of seconds all that horrible hash disappears just leaving the station you want to listen to.
Noise cancelling can be varied between 9 and 35db by DIP switches on the back. I run the unit at fairly low levels of cancelling – this is easier to work with in QSOs as the NES 10-2 can take a little time, 2-3 seconds, to adjust at high levels of cancellation. You can also get a water-fall effect at high levels which is strange to hear but still effective. I decided to set the filtering at level 6.
Feedback problems
The NES 10-2 is susceptible to RF feedback which can be a real problem…usually when working DX of course! Tony, G0DLX, found a solution to this – provide a separate power supply from the shack supply. I tried this and found it improved matters enormously. A random power supply was pressed into service with some resistors to bring the voltage down to supply all the shack audio devices – BHI NES 10-2 and Datong FL-3 filter.
Incorporation into my Yaesu SP-6 Filter Speaker Unit
As the SP-6 box has a large area of space inside it the NES 10-2 fits very neatly inside. Both the SP-6 and the NES 10-2 operate on 8 ohms so no impedance problems.
Other than the front panel switch, I simply took the front and speaker off the NES 10-2 and cable tied it to the back panel! I left enough wire on the input, output and power connectors to put the device back together again later if required.
The notes below are more for my purposes really…
DSP is switched in via a front panel DPDT switch in the connection to the speaker. When switched out it passes the audio straight through, when switched in, it passes the audio to the input of the NES 10-2 (black+white wire). The output from the NES 10-2 (grey wire) goes back the the DPDT switch to route through to the speaker. The NES 10-2 black (input) and blue (output) are connected together and grounded with the SP-6 box. The power connector (red/black wires) was simply extended and remounted on the back panel of the SP-6.
I’m also controlling a fan unit behind the equipment via the Fan switch which I’ve mounted on the front-panel and simply dropping the 13.8v supply voltage to around 10v with resistors.
Last updated Oct 2022