LRR10- NOISE REDUCTION AF FILTER


HF NOISE REDUCTION AF FILTER LRR10

N.Ganesan,VU3GEK-KJ6LRR

(UNDER TESTING)

The LRR10 is a high performance versatile audio filter that can be used with any receiver or transceiver. It can improve intelligibility of CW, phone, or data signals, and is especially well suited to radios that have inadequate I.F. or audio filtering. The LRR10 uses straightforward analog circuitry and no surface-mount components, so it’s an ideal DIY project for Home brewers.

Low-noise analog variable audio filter circuit used here is a low-pass filter with switched capacitors, elliptical, of 8th order for improved audio easily compares the reception with that of a receiver equipped with DSP filter.

This circuit design follows a standard well-proven approach based on various kits available on WWW modifications have been done.

Features & specification :
  • Variable Filter Bandwidth approx. 600-4000 Hz
  • 2Watts Dc controlled audio amplifier.
  • PCB Size 92 x 60 mm.
  • 12VDC Power.
  • Available as a DIY kit or fully assembled high quality components for reliable operation.
BOM:
  
S.No
Ref Des
Part No
QTY
1
U1
7806
1
2
U2
MAX293
1
3
U3
TDA1013
1
4
D1
IN4007
1
5
D2
BB112
1
6
D3
LED
1
7
R1
39Ω/0.5W
1
8
R2
180Ω
1
9
R3
100Ω
1
10
R4
1KΩ
1
11
R5/R6/R8
10KΩ
3
12
R7
100KΩ
1
13
R9
470Ω
1
14
R10
4K7Ω
1
15
R11
150KΩ
1
16
R12
4E7Ω
1
17
R13
39Ω
1
18
C1/C6
100µ/25V
2
19
C2/C4/C8/C9/C13/C14/C15/C16/C18
0.1µF/104/100N
9
20
C3/C5
0.01µF/103/10N
2
21
C7/C10
1µ/25V TAN
2
22
C11
0.001µF/102/1N
1
23
C12
33µ/25V
1
24
C17/C19
470µ/25V
2
25
P1
500Ω TRIMPOT
1
26
P2/P2
10K POT-PCB
2
27
CN1
DC SOCKET
1
28
CN2/CN4 -MONO
3.5MM SOCKET
2
29
CN3-STEREO
3.5MM SOCKET
1
30
PCB
6Omm X 92mm
1

 

 

CONTACT DETAILS:

N.Ganesan

ganesan4u@hotmail.com

09363105352

Coimbatore

Tamil Nadu

India

1 comment:

  1. An Excellent piece of work done. The latest design I brought has LM-380 replacing U3. Those who are really knows about the audio spectrum, will love to test it for once.
    Add it as a I/P Pre-amp and O/P Audio amp in BITX, and see the difference.

    De SWL Gurudatta

    ReplyDelete