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DM41X Progs

BFil

LBL ¬BFIL
SF 00
¬MHZ ?
PROMPT
1 E6
*
STO 11
¬N
PROMPT
x<0?
CF 00
STO 10
XEQ 06
LBL 01
RCL 12
INT
XEQ 00
FS? 00
1/x
STO IND 12
ISG 12
GTO 01
¬COEFFICIENTS
FIX 3
STOP
ENG 3
XEQ 06
LBL 02
RCL 12
INT
RCL IND 12
RCL 11
2
*
PI
*
/
STO IND 12
ISG 12
GTO 02
XEQ 06
LBL 03
RCL 12
INT
2
/
FRC
FS? 00
GTO 09
GTO 10
LBL 09
¬HPF
x=0?
GTO 05
GTO 04
RTN
LBL 10
¬LPF
x=0?
GTO 04
GTO 05
RTN
LBL 04
RCL IND 12
50
*
STO IND 12
ISG 12
GTO 03
RTN
LBL 05
RCL IND 12
50
/
STO IND 12
ISG 12
GTO 03
RTN
LBL 06
RCL 10
ABS
1000
/
1
+
STO 12
RTN
LBL 00
2
*
1
-
180
*
RCL 10
ABS
2
*
/
SIN
2
*
RTN
END

Examples

5MHz 5-pole LPF

XEQALPHABFILALPHA

MHZ ?

5 R/S

Order/poles = N Positive for HPF Negative for LFP

5CHSR/S

COEFFICIENTS
0.618

(at this point you can RCL 01 etc. up to RCL 05 to see the calculated Butterworth Coefficients)

R01 : 0.618
R02 : 1.618
R03 : 2.000
R04 : 1.618
R05 : 0.618

R/S

LPF
393.5 -12

The calculated component values are now in Reg 01 - Reg 05

R01 : 393.5pf
R02 : 2.575uH
R03 : 1.273nF
R04 : 2.575uH
R05 : 393.5pF

Page Info

Page created Thu May 26 18:35:00 2022 by John Pumford-Green

Page last updated: 06/03/25 06:49 GMT

dm41x, calculator

John's Vademecum

Table of Contents

DM41X Progs

BFil

Examples

5MHz 5-pole LPF

Page Info