TS-5700
AT INPUT
CM
Coupler
CIRCU IT D ESCRI PTI O N
V&I
Detector
IZI
0
r----------------------1
:
Through
:
I
I
I
I
Load
ZL ZL=RL+jXL
Unknown
•
IF Filter Switching
AID
VSWR=
I
Converter
2VSFM+VSRM
VSWR
VSRM
2VSFM-VSRM
L_
_____
_J
Fig.
1 6
AT control block diagram
The IF filter bandwidth changes automatically as
the mode changes. Its details are given below.
I F fi lter b a n dwidth
Y K-88S N - 1 ( 1 800 Hz)
Y K-88C-1 (500 Hz)
CW ( Hz)
F S K ( Hz)
CW ( Hz)
F S K ( Hz)
2 . 4kHz
2 O k
1 . 5k
1 O k
1 O k
B a n dwidth o f the i n sta l led fi lter
1 . 0 k o r less
1 . 0 k or less
600 or less
500 o r less
•
Receive Ban d- Pass Filter Selection
•
E l ectro nic Keyer
Y K-88C N - 1 (270 Hz)
CW ( Hz)
300 o r more
200 or less
The RF BPF signal from the control unit is sent to
the TX-RX unit as serial data. The serial-to-parallel con
verter in the TX-RX unit converts serial data to parallel
data and switches between band-pass filters.
T h e T S - 5 7 0 D u s e s a d e d i c a t e d IC ( I C3:
•
Transmit Low-Pass Filter Selection
The LPF signal from the control unit is sent to the
final unit as serial data. The serial-to-parallel converter
in the final unit converts serial data to parallel data and
switches between low-pass filters.
UPD75004GB-746) to control the electronic keyer.
The main CPU reports CH 1 to CH3 switch operations
to the electronic keyer IC (keyer microcomputer).
1 9