Vertex Standard FT-1000MP - Manual (Page 75)

Page 73 O
PERATING
M
ANUAL
Advanced Features
EDSP
EDSP F
UNCTIONS
The EDSP circuitry in the MARK-V FT-1000MP
Field
allows digital enhancement of both transmitted and re-
ceived audio. A basic primer on DSP was given to in-
form you more about this capability than just the panel
label and button location. Now you can customize its
filtering capabilities and use it to reduce QRM and tai-
lor audio response for each operating mode.
EDSP Modulation
TX Audio Enhancement (Menu 4-4)
Four microphone audio responses can be chosen
using menu selection 4-4. Since voice audio character-
istics vary between people, these settings enable tai-
loring your transmitted audio for best clarity.
TX IF Filter Selection (Menu 5-9)
Normally, 2.4 kHz filters are selected for both the
455 kHz and 8.2 MHz Tx IF. However, with EDSP op-
eration, you can keep the 2.4 kHz filter, or select the
6.0 kHz filter for maximum bandwidth and better fre-
quency response on your transmitted audio. The re-
sulting effect of this filter selection is directly related to
menu selection 7-7 (below). The desired filter is chosen
with menu selection 5-9, and is only active when EDSP
is turned on. Note that your signal’s actual bandwidth
on SSB will not exceed that set by the IF analog filter,
with a (-6 dB) bandwidth of approximately 2.4 kHz be-
ing typical.
EDSP Modulation/Demodulation (Menu 7-7)
TX EDSP Modulation - Early-stage transmitted
SSB audio may be applied directly to the EDSP cir-
cuitry for processing, bypassing the analog modulator.
EDSP filter parameters can be matched to voice char-
acteristics for optimum audio tailoring.
RX EDSP Demodulation - For SSB, CW and AM,
receiver 3rd IF output is applied directly to EDSP cir-
cuitry for demodulation and processing, bypassing the
analog product detector. Reduced noise is a primary
benefit of the EDSP Demodulator, which may be used
alone or in conjunction with EDSP filtering.
Menu selection 7-7 configures the settings for both
the R X and T X EDSP modulation circuits (see table at
the right). Note also that if the EDSP is turned off via
menu selection 0-9, these circuits will revert to their ana-
log counterparts.
EDSP RX A
UDIO
E
NHANCEMENT
EDSP Contours
QRM reduction is accomplished by uti-
lization of the various DSP filter networks.
The front CONTOUR buttons select Low-
(
button,) Mid- ( button,) and High-
cut ( button) filters, along with a band
pass filter selection (see below).
The low-, mid-, and high-cut filters are
pre-set for different audio emphasis, using
mathematical algorithms developed after
thousands of hours of on-the-air testing.
The bandpass filter, activated when the [IDBT] button
on the Shuttle Jog is pressed, is automatically pro-
grammed to match the analog IF passband established
by the setting of the WIDTH and SHIFT controls. No
manual adjustment is required.
This CONTOUR LED indicates the current status
of the EDSP Contour feature:
Glowing Green: Low-cut filter selected,
Glowing Orange: Mid-cut filter selected,
Glowing Red: High-cut filter selected,
Off: EDSP Contour Off.
In actual operation, it may be very difficult to “pre-
dict” which Contour response will best enhance the sig-
nal-to-noise recovery. So under difficult conditions, you
should change selections often; don’t be surprised if
one selection suddenly causes the incoming signal to
“jump” out of the background noise.
EDSP CONTOUR S ELECTIONS
CONTOUR
Selection
Filter Type
LCF (Low - Cut)
MCF (Mid - Cut)
HCF (High - Cut)
Application
high-freq. empasis
high & low freq.
empasis
low-freq. empasis
EDSP M ODULATION & D EMODULATION
M ENU S ELECTION “7-7”
Mode
SSB (RX)
SSB (TX)
CW (RX)
AM (RX)
Settings
OFF
100 ~ 3100 Hz
300 ~ 2800 Hz
OFF
100 ~ 3100 Hz
150 ~ 3100 Hz
200 ~ 3100 Hz
300 ~ 3100 Hz
OFF
ON (100 ~ 3100 Hz)
OFF
ON (70 ~ 3800 Hz)