Transmission And Sub Receiver Blocks; Mlo1/Mlo2 Frequency Shift Data - Kenwood TS-990S Service Manual

TS-990S
● IF=8.248MHz
Frequency: 0.03 ~ 60MHz
MAIN RX
MLO1
RX  26.5
Mode offset 1 +(MDSPFC) +(MDSPFC) +(MDSHIFT) +(MDSHIFT) -(MDSPFC) -(MDSPFC) -(MDSHIFT) -(MDSHIFT) +(CW SHIFT) +(CW SHIFT) -(CW SHIFT) -(CW SHIFT)
MAIN RIT (MRIT)
IF8M_2.7k +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1)
MAIN CAR IF8M_500 +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2)
IF8M_270 +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3)
MAIN RX
MLO1
RX  26.5
Mode offset 1 0
MAIN RIT (MRIT)
IF8M_2.7k +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1) +(MCAR1) -(MCAR1)
MAIN CAR IF8M_500 +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2) +(MCAR2) -(MCAR2)
IF8M_270 +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3) +(MCAR3) -(MCAR3)
MLO2
RX  26.5
Mode offset 1 +(MDSPFC) -(MDSPFC) +(MDSHIFT) -(MDSPFC) -(MDSPFC) +(MDSPFC) -(MDSHIFT) +(MDSPFC) +(CW SHIFT) -(CW SHIFT) -(CW SHIFT) +(CW SHIFT)
IF8M_2.7k +(MCAR1) +(MCAR1) +(MCAR1) +(MCAR1) +(MCAR1) +(MCAR1) +(MCAR1) +(MCAR1)
MAIN CAR IF8M_500 +(MCAR2) +(MCAR2) +(MCAR2) +(MCAR2) +(MCAR2) +(MCAR2) +(MCAR2) +(MCAR2)
IF8M_270 +(MCAR3) +(MCAR3) +(MCAR3) +(MCAR3) +(MCAR3) +(MCAR3) +(MCAR3) +(MCAR3)
MLO2
RX  26.5
Mode offset 1
IF8M_2.7k
MAIN CAR IF8M_500
IF8M_270
( MRIT): Main RIT frequency variable amount (–9.99~+9.99kHz)
(FSK SHIFT): FSK shift width frequency (170Hz, 200Hz, 425Hz, 850Hz, and initial value: 170Hz)
(CW SHIFT): CW shift amount
CAR correction: SSB IF-Filter adjustment range (The range is set to zero when an additional roofi ng fi lter is used.)
(MCAR1): Main, IF fi lter (2.7kHz) correction value
(MCAR2): Main, IF fi lter (500Hz) correction value
(MCAR3): Main, IF fi lter (270Hz) correction value
(MDSPFC): Varied with the DSP fi lter set value
(MDSHIFT): DATA mode shift width frequency set value

2. Transmission and Sub Receiver Blocks

2-1. Frequency Confi guration
When transmitting in FM mode, it works in double conver-
sion, and when transmitting in AM, SSB, CW, FSK or PSK
mode, it works in triple conversion.
While sub receiving, the 1st IF works in 73.095MHz triple
conversion. In modes other than FM, the 3rd IF works in
24kHz, and the IF signal is converted by an A/D converter
(ADC) and is applied to DSP. In FM mode, the audio signal
is discriminated by the FM IC, and is converted into the digi-
6
CIRCUIT DESCRIPTION
USB USB-DATA
26.5  RX RX  26.5 26.5  RX
(MRIT) (MRIT) (MRIT)
PKS PKS-R
26.5  RX RX  26.5 26.5  RX
0 0 0
(MRIT) (MRIT) (MRIT)
USB USB-DATA
26.5  RX RX  26.5 26.5  RX
PKS PKS-R
26.5  RX RX  26.5 26.5  RX
0 0
+(MCAR1) +(MCAR1)
+(MCAR2) +(MCAR2)
+(MCAR3) +(MCAR3)
Table 1 MLO1/MLO2 frequency shift data
DDS AD9951 (MDEN1)
LSB LSB-DATA
RX  26.5 26.5  RX RX  26.5 26.5  RX
(MRIT) (MRIT) (MRIT)
DDS AD9951 (MDEN1)
FSK FSK-R
RX  26.5 26.5  RX RX  26.5 26.5  RX
-(FSK SHIFT/2) -(FSK SHIFT/2) -(FSK SHIFT/2) -(FSK SHIFT/2)
(MRIT) (MRIT) (MRIT)
DDS AD9951 (MDEN1)
LSB LSB-DATA
RX  26.5 26.5  RX RX  26.5 26.5  RX
DDS AD9951 (MDEN1)
FSK FSK-R
RX  26.5 26.5  RX RX  26.5 26.5  RX
0 0
+(MCAR1) +(MCAR1)
+(MCAR2) +(MCAR2)
+(MCAR3) +(MCAR3)
tal signal by an ADC and then is applied to the DSP. Under
the following conditions, the 1st IF of the sub receiver block
works in 11.374MHz double conversion.
1) Modes other than AM or FM
2) 1.8/ 3.5/ 7/ 14/ 21MHz amateur bands
3) DSP fi lter's bandwidth is 2.7kHz or lower
CW
RX  26.5 26.5  RX RX  26.5
(MRIT) (MRIT) (MRIT) (MRIT)
AM
RX  26.5 26.5  RX RX  26.5
0
(MRIT) (MRIT)
CW
RX  26.5 26.5  RX RX  26.5
+(MCAR1)
+(MCAR2)
+(MCAR3)
AM
RX  26.5 26.5  RX RX  26.5
0
CW-R
26.5  RX
(MRIT)
FM (FM-DATA)
26.5  RX
0
(MRIT)
CW-R
26.5  RX
+(MCAR1)
+(MCAR2)
+(MCAR3)
FM (FM-DATA)
26.5  RX
0