Please visit my page.Assembled New Soft66AD is arriving. New Soft66Lite kit is released now.


NOTE:SMA Jack is not including.

Soft66RF is newest version of Soft66 series. Soft66RF have 4 band pass filter with micro inductor.You  do not need to wind troido core.It is easy assembling. Default frequency is 7.056MHz.Please ask me another frequency.
example: you want to recieve 7.02MHz ->28.08MHz
14.12MHz 14.7456MHz 16.9344MHz 20.0MHz 22.684MHz 28.08MHz 28.12MHz 28.16MHz 28.6363MHz 3.520MHz 42.8MHz 43.1MHz 43.4MHz 50.150MHz 56.448MHz 7.003MHz 7.005MHz 7.01MHz($2USD each)

Soft66RF have 2 type of power line. NJM2068 is working at 9V. It is more clear signals. Soft66RF is more sensitive with J310 RF amplifire at high band.

Connecting DDS-34 or DDS-BASE, Soft66RF become powerfull SW radio up to 30MHz. If you select DDS-BASE, there is less spurius.

you can use long wire antenna adding balan on PCB for SWL user. It is very usefull on AM receiving.

If you have question. please mail to ja7tdo<atmark>
Soft66 is one of the GAS project.SOFT66is release on open source design.

Kazunori Miura


 right click for large image

 new version(red pcb)

attatch DDS-34B to Soft66RF

first, insert 14pin IC socket into IC5. second, remove solder of SJ4.

instruction for Soft66RF(basic type)

1.Check your packing

Please check your packet according to PartsList.

2.setting jumper

first, please jumper ON with solder side of PCB.

Please jumper ON SJ4.

If you receive low band, I reccomend you SJ3 is ON. It is no need to build RF block.


Please assemble components according to this image.You can look larger image with right click and view image.
Please note SMA Jack is NOT including.

You can add balan for long wire antenna. Please use T37-43. winding 11 turns with 0.23mm or 0.26mm wire to trifiler.
A,B,C is silk mark on PCB.

4.Connecting to PC

Please connecting Jack to your PC Line input. Plug DC power about 12V to 20V.
You need also install Rocky or SDRadio.

5.optional BPF

It is enable to add optional 3BPF on Soft66RF.Please look inductor and capacitor value.

middle wave:400kHz〜1600kHz(L1,L3->5.6uH L2->26uH(22uH+5.6uH) or 27uH C1,C3->5600pF C2->1000pF)
160m:(L1,L3->2.2uH L2->16uH(10uH+5.6uH) C1,C3->3300pF C2->470pF)
80m:(L1,L3->2.2uH L2->5.6uH C1,C3->1000pF C2->470pF)
20m:(L1,L3->0.27uH L2->3.3uH C1,C3->680pF C2->40pF(20pF+20pF))
15m:(L1,L3->0.27uH L2->2.7uH(2.2uH+0.47uH) C1,C3->560pF C2->20pF)


U$4             2SC1815 or 2SC1674                       

IC4       74AHC4066 or 74VHC4066 or 74HC4066     

IC1                    74AC74                  

IC2        78L05                                  

IC3        78L09                                  

BPF parts  C23,C22=1000pFx2 or (680pF + 220pF) x 2 ,C21=100pF or 120pF,T2=6.8uH or 5.6uH,T1,T3=0.68uHx2 or 0.47uH  

C27,C28       0.01uF(103)     Ceramic Capacitor   

C2,C3,C4,C5,C14,C15    0.1uF(104)    Ceramic Capacitor   

C7,C9     1000pF or 680pF      Ceramic Capacitor      

C8,C11,C16,C17     100pF or 120pF  Ceramic Capacitor

C1       10uF  or 2.2uF       tantalum capacitor            

C12,C13        1uF(105) or 2.2uF or 3.3uF    capacitor  

C32,C33       330pF  Ceramic Capacitor                  

C6,C10       47uF       electrolysis capacitor               

D1        1N4004        diode      

Q1  HC49US     crystal resonator                       

L9     1uH     inductor                          

L4,L8   22uH or 47uH        inductor          

U$5        J310 or 2SK192     RF増幅                                     

JACK                please cut inside pins        

IC6           NJM2068D        operational amplifiere                  

R1,R8        1.5kΩ       register      If you need more gain, R1 is 100 ohm.                

R10,R11 -> 100ohm

R4,R7           2.2kΩ       register                    

R3        47kΩ       register                      

R2,R9,R5,R6        5.1kΩ       register              

LINK inductor color code