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Page 19

NEDSP1062-KBD  Operating Manual

Figure 16. Circuit modification for low power signal drive.

3.3 Driving from a low signal source.

The input to the module has a low impedance. This is to
provide correct loading to any power circuits driving it. If
the module needs to be driven from a low power signal
then it must be modified in the following manner.

Cut the

leg on this

resistor

3.

Installation.

22

W

OUT

12

Agnd

Agnd

9

10

Load

V

Audio

Input

NEDSP1062

R6

IN

11

Circuit

modification

Figure 15. Physical modification for low power signal
drive.

Note:

Wiring

omitted for

clarity.

Summary of Contents for NEDSP1062 KBD

Page 1: ...Page 1 NEDSP1062 KBD Operating Manual bhi bhi bhi bhi bhi NEDSP1062 KBD Amplified Noise Eliminating DSP Module Installation and Operating Manual Sound Engineering Solutions from bhi 1062 107D Issue D ...

Page 2: ...td Disclaimer The information in this document is subject to change without notice bhi Ltd makes no representations or warranties with respect to the contents hereof and specifically disclaims any implied warranties of merchantability or fitness for any particular purpose Furthermore bhi Ltd reserves the right to revise this publication and to make changes from time to time in the content hereof w...

Page 3: ...rols 12 2 4 2 Keyboard 12 2 5 Electrical characteristics 12 3 Installation 3 1 Installation overview 16 3 2 Module setup 17 3 2 1 Overview 17 3 2 2 Suggested set up procedure 17 3 2 3 Changes to output load 18 3 2 4 Other signal considerations 18 3 3 Driving the module from a low level signal 19 4 Functions 4 1 Keyboard 20 4 1 1 Power button 20 4 1 2 DSP level button 20 4 2 Set up 21 4 3 Demonstra...

Page 4: ...age 4 NEDSP1062 KBD Operating Manual 6 Physical dimensions 6 1 Physical dimensions 32 6 2 Keyboard hole drilling detail 35 7 Troubleshooting Troubleshooting 37 8 Other bhi products Other bhi products 38 ...

Page 5: ...ly adaptive noise cancellation up to 35dB Input and output level controls Input level over load indication Virtually no distortion to speech signal Easy to install 4 8 levels of noise reduction selectable Frequency response 50Hz 4 3KHz 3 Watts output 4W Single button operation of DSP mode with LED and audible indication 12 18V supply range 27dB on board gain Power on off bypass pushbutton Small si...

Page 6: ... a low power signal see section 3 3 for more information The module can be mounted using the supplied self adhesive foam pad Ensure that none of the circuit pins can make contact with any metallic parts For improved heat dissipation and a more rigid mechanical fixing the heatsink can be reversed and used as a bracket Note that the heatsink is at 0V potential and therefore may have to be electrical...

Page 7: ...thermal paste between the power devices and the mounting Figure 2 Direct mounting Figure 3 Keyboard mounting 1 The keyboard is mounted through the enclosure to provide an easy to use interface The module is supplied with a label to place over the keyboard When the enclosure is thick enough the keyboard is retained using a countersunk screw supplied which is hidden by the label see figure 3 above D...

Page 8: ... carefully cutting around the screw hole with a sharp knife Again do not over tighten the screw Nut washer Front panel label keyboard Retaining screw Front panel 1 5 Sounder mounting Cut a small piece of the self adhesive foam supplied to mount the sounder Do not cover the small hole in the face of the sounder For best results mount the sounder where it can radiate sound to the outside the case fo...

Page 9: ...e The unwanted noise and interference is then attenuated to leave only the speech The following diagrams are taken from actual audio signals and illustrate how the signal is being processed Figure 6 Noise cancellation Original signal Speech with a lot of background noise Processed speech Speech with reduced noise Speech Noise Reduced noise 1 Introduction ...

Page 10: ...ion Output level set Power Amp BCD DSPlevel select Xtal Clock generator DSPcore 5V 5V Regulator Latch 12V regulator 3 3V regulator 3 3V 12V Relay Drive Relay 1 ON 14 Analogue to Digital conversion 7 0V 10 12 6 Power supply section PCB Connections 13 5 J3 Input Load resistor Agnd Agnd Vin NC NO NO NC DSP 3V3 0V PCB microcontroller 4 Keyboard interface 8 N C N C Relay 1 Out 11 2 1 Block diagram 2 Mo...

Page 11: ...o be processed 10 Out Audio output Procesed audio signal out 11 Agnd 0V for input audio signal Analogue ground for audio in 12 Agnd 0V for output audio signal Analogue ground for audio out Table 1 NEDSP1062 connection functions 2 Module description Figure 8 NEDSP1062 KBD connections and controls Input level set P2 Output level set P1 Input overload indicator LED Mounting holes Audio bypass relay T...

Page 12: ...ve end stops so it is possible to set them in a position where the audio will be lost Audible indication of operation is provided by an piezo sounder The volume of this sounder can be varied by potentiometer P3 The sounder volume is independent of the incoming audio volume 2 4 2Keyboard The keyboard controls all of the module functions including power on off 2 Module description Figure 9 NEDSP1062...

Page 13: ...onditions Min Typ Max Units Po Output power d 10 f 1KHz RL 8W RL 4W 12V 1 16 1 7 16V 18V 2 06 3 17 Vs W W Vi Input sensitivty 4W load f 1KHz PO 0 5W PO 1 0W PO 2 0W 60 90 130 mV Vi Input sensitivty 8W load f 1KHz PO 0 5W PO 1 0W PO 2 0W 81 117 180 mV B Frequency response 3dB Po 1W RL 8W 50 4300 Hz d Distortion f 1KHz PO 0 2 2 4W R L 8W PO 0 2 2 4W R L 4W 0 8 0 8 Ri Input resistance 21 22 23 W Gv V...

Page 14: ...0 1000 2000 3000 4000 5000 6000 Figure 10 Frequency response Frequency Hz Output dB 0 2 4 6 8 10 12 0 0 5 1 1 5 2 2 5 3 3 5 Figure 11 Distortion vs Output power Distortion Output power W VS 16V f 1KHz RL 8W RL 4W 2 Module description RL 8W VS 16V P 1W 3dB ...

Page 15: ...Page 15 NEDSP1062 KBD Operating Manual Figure 12 Sensitivity 0 0 5 1 1 5 2 2 5 0 50 100 150 200 Input voltage mV Output power W RL 8W RL 4W VS 16V f 1KHz 2 Module description ...

Page 16: ... provide a dummy load to the preceding circuit This can be removed if required such as using the module in applications where the audio source is provided by a low level low power signal source More information on this can be found in section 3 3 in this operating manual If Vin is less than approx 13 8V ensure the power supply is well decoupled otherwise the power supply rejection ratio will deter...

Page 17: ...g P3 To obtain the best results from the noise reduction the module should be set up to give optimum performance The input sensitivity control has a range of 0 70mW 3W to provide 2W W output Under certain conditions RF breakthrough can sometimes occur To minimize this the input level P2 may need to be reduced or go to the FAQ page on the bhi website and download the FAQ on RF breakthrough Under ce...

Page 18: ...ay may be heard when the audio signal changes For optimum performance provide the module with a constant signal where possible When switching on the unit a thump may be heard in the loudspeaker 3 Installation Figure 14 Input circuit module powered down 22W OUT 12 Agnd Agnd 9 10 V Audio Input NEDSP1062 R6 IN Load 11 The audio input to the module is loaded at 22W This load is effectively connected a...

Page 19: ... to provide correct loading to any power circuits driving it If the module needs to be driven from a low power signal then it must be modified in the following manner Cut the leg on this resistor 3 Installation 22W OUT 12 Agnd Agnd 9 10 Load V Audio Input NEDSP1062 R6 IN 11 Circuit modification Figure 15 Physical modification for low power signal drive Note Wiring omitted for clarity ...

Page 20: ...ugh the module Note If the power is on and the DSP is switched off the audio still passes through the DSP but without any signal processing A single press on the button switches on and a single press will switch off Also with the power connected and the module switched off the circuit will still draw 6mA 4 1 2DSP level button This button is used to set the following DSP on off DSP level 4 or 8 lev...

Page 21: ...on 4 2 Set up The following flow chart shows the functions of the DSP button Releasing the DSP button at this point the module goes in to demonstration mode 1 Keep the button down until the desired level has been reached then release the button The module will continously scroll through 4 and 8 levels until the button is released Figure 18 4 8 level setting Holding down the DSP button when switchi...

Page 22: ...et up mode Releasing the button after the first 2 tone beep will enter demonstration mode 1 Releasing after the second 2 tone beep will enter demonstration mode 2 Keeping the button depressed with change the number of levels available 4 beeps will indicate 4 level mode and 8 beeps 8 levels Release the button when the desired level is reached The module will return to normal operation after this Th...

Page 23: ...conds then off for 3 seconds This is a good demonstra tion of the before and after effects of remov ing the noise Demonstration 1 The module switches the noise cancellation on for 1 5 seconds then off for 1 5 seconds It will then move to the next level and repeat the process This mode is particularly effective at demonstrating the different DSP levels Alternatively pass a clean audio signal throug...

Page 24: ...B 1 2 5dB 11dB 3 6dB 13dB 2 4 8dB 15dB 5 16dB 17dB 3 6 21dB 20dB 7 25dB 24dB 4 8 65dB 35dB Table 4 Tone and noise reduction levels The column marked level 4 shows the noise and tone reduction when operating the module with 4 levels and the level 8 column for 8 levels Holding down the DSP select button will continuously change the DSP level When the desired level has been reached release the button...

Page 25: ...a Yaesu SP8 5 1 Yaesu SP8 This section describes the general fitting of the NEDSP1062 KBD module in the Yaesu SP8 loudspeaker This installation retains the operation of the internal filters DSP Keyboard Figure 21 Suggested location of power connector Figure 22 Suggested location of keyboard This photograph shows the suggested location for mounting the keyboard Suggested location for mounting the p...

Page 26: ... jack unit Locate the 2 wire connector on the switch unit JP2002 Break the wire to pin 1 and wire as shown in the diagram Insulate the connection with the supplied rubber sleeve Break the wire on pin 2 on JP2002 and connect as shown in the diagram and again insulate with a rubber sleeve The fitting kit includes cable ties to tidy up the wiring of the installation The photograph on the next page sh...

Page 27: ...Page 27 NEDSP1062 KBD Operating Manual Figure 24 Complete installation in the Yaesu SP8 DSP module Input PCB Power connector 5 Applications ...

Page 28: ...es the general fitting of the NEDSP1062 KBD module in the Kenwood SP31 loudspeaker This installation retains the operation of the internal filters Figure 26 Suggested location of keyboard Figure 27 Suggested location of power connector Suggested location for mounting the power connector This photograph shows the suggested location for mounting the keyboard ...

Page 29: ...ore the filter PCB Identify the yellow wire connecting the input selector switch to the filter board Break the wire and connect the NEDSP1062 KBD as shown below Insulate the wires with the supplied rubber sleeves Identify the black wire from the input PCB and connect as shown below again insulating the connections The fitting kit includes cable ties to tidy up the wiring of the installation The ph...

Page 30: ...DSP1062 KBD Operating Manual Figure 29 Photograph of complete installation Sounder NEDSP module screwed to the case using an existing hole Input selector switch Filter PCB DSP connections Keyboard 5 Applications ...

Page 31: ... KBD Operating Manual Figure 30 bhi label 5 Applications 5 3 bhi Label Supplied with the module is a square bhi label Fix the label on the top of the speaker enclosure as shown bhi bhi bhi bhi bhi DSP Noise Cancellation ...

Page 32: ...4 2 97 30 3 34 3 36 5 49 6 2 97 Pin 1 3mm dia 6 Physical dimensions 6 Physical Dimensions Figure 31 Mounting hole positions Top 6 1 Physical dimensions The following diagrams detail the physical dimensions of the module All dimensions are in mm ...

Page 33: ...Manual 6 Physical dimensions Components fitted to rear of PCB Figure 32 Overall dimensions Figure 33 Hole dimensions of power devices for direct mounting applications 16 1 5 3 17 9 16 4 Viewed from the end of the module 34 2 64 4 5 8 ...

Page 34: ...Page 34 NEDSP1062 KBD Operating Manual 6 Physical dimensions Figure 34 Keyboard dimensions Figure 35 Power connector hole size 29 8 25 3 20 2 13 4 6 8 9 5 4 7 7 5 3 2 10 9 5 5 3 8mm diameter ...

Page 35: ...6 Physical dimensions 6 2 Template The following drawing shows the sizes and positions of holes for the keyboard Figure 36 Keyboard drilling detail Not to scale all dimensions in mm 29 8 18 5 13 4 6 7 6 7 10 9 5 5 4mm 4mm 4mm 3mm CSK to 5mm ...

Page 36: ...Page 36 NEDSP1062 KBD Operating Manual This page is intentionaly blank ...

Page 37: ... Input level too low Increase supply voltage Finish Yes Disconnect R6 see section 3 3 Over load LED illuminates Add additional amplification No Yes No No Yes 7 2 Insuffucient output volume 7 Troubleshooting Input signal Overload LED on Reduce input level Increase output level P1 Apply audio signal Increase input signal P2 No Yes No Yes Audio out Finish Start Yes No 7 1 No audio out 7 Troubleshooti...

Page 38: ...cancellation On Off switch LED indication of power and noise cancellation 12 24VDC operation On Off audio bypass switch Greatly improved signal to noise ratio Easy to install with adjustable mounting bracket 2m audio lead Optional extras avaiable 8 1 NES10 2 MKII Noise Eliminating speaker Basic plug and go noise cancelling speaker preset to 20dB of noise reduction Features Fully adaptive noise can...

Page 39: ...sitivity control Noise cancellation On Off switch Line level in out Input overload indication Power on off with audio bypass 8 4 NEIM1031 accessories 8 5 DSP modules LSPKR 20 Watt extension speaker for use with the NEIM1031 Fitted with a 3 5mm mono jack plug 1031 STA Mounting stand for the NEIM1031 Allows the NEIM1031 to be ad justed for the most comfortable operating postion 8 Other bhi products ...

Page 40: ...perating Manual bhi Ltd P O Box 318 Burgess Hill West Sussex RH15 9NR tel 44 0 845 2179926 fax 44 0 845 2179936 sales bhi ltd co uk www bhi ltd co uk bhi bhi bhi bhi bhi DSP Noise Cancellation Products DSP Noise Cancellation ...

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