Yaesu FT-101EE - High Frequency

The transceiver has adaptec computor type plueein
1 a |
wh
frequeney EF unit, OW frequency IF unit, Audio unit
modules; These modules are: High frequeney unit, |
Modulator unit, Nose blanker unit antl Power reeulatot
unit, In addition, the VFO unit, Crystal osertater unit
and Rectifier umit-are built-in to the main chassis.
(1) HF UNIT (PBI1éIB})
This module contains the receiver RF amplifier, receiver
lst mixer, transmitter 2nd mixer and heterodyne oscil
later cireun. The signal from the antenna coil is fed
ta the gate of Q1 (field effeet transistor SSK40™M)
through terminal & of the module
The AGC (automatic gain control) voltage which 15
obtained from the low frequency IF unit, is applied
to the gate circuit of @1 from pm -§ to control the
cain of this stage. A manual RF gain control on the
front panel ts connected to the source of Q1] through
pin 10,
Signal output from the @1 is then coupled te the
recenver first mixer G2. 2SKIGGR where the meoming
signal is mixed with a signal from the heterodyne
oscillator (yd, 2SCA72Y throweh the buffer stage Qs,
Z2ouero. Phe produet of the first mixer is app
ean set la
wd fram
the pin 17 to the high frequency IF unt.
Transmitter signal is fed to the base of transmitter 2nd
mixer Q3, 2SC7S84R from pin 13. The signal from the
heterodyne
oasciliter
is
appled
to
the
emitter
of
the
mixer Q3, thrauth the buffer stame Q4, 2SCa72Y. This
arrangement converts the hich frequeney [F signal to
the desired transmitting Trequeney. This transmitting
sitnal is fed ta THI through pin i. The gate circuit of
the receiver mixer G2 is disconnected in transmit by
dim switch to avoid the lowering the Q of the circuit,
Crystal sockets.and all coils are mounted on the main
CeLSSLa,
(2) HIGH FREQUENCY IF UNIT | PB1I80B)
The module contains the transmitter first mixer QI,
PSC37ZY, the receiver second mixer G2, SSRKAUM,
and 5520 to 6020) KHz bandpass network, The signal
from the receiver first mixer is fed to the gate of the
5 Q, Q, Q,
PB-1181
mixer through the bandpass netwark Ll, L2, and Ld,
fram pin 15, VFO voltage is also appliecdto the 2nd gate
at Q2 from pin 11. The signal is converte! ta 3180
KHz low frequency IF and fed to the following Stage
from pin 4 through an output transformer T1124. On
Eransmit, the SEA0 KHz sienal is fel to the base of
the mixer, from pin 6; A 14 MHz trap coil T113 ts
connected in the base circuit of QL. The VFO) signal
ss fed to the emitter af the Q1 whith preduces the
sare) to 6020) KHz high frequenevy IP signal, This
signal is fed to the following stage from pin l6 through
the bandpass network
T. Q, x. Te Ti;
PB-1180
*y
‘di
BANDPASS NETWORK CHARACTERISTICS
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