FT-950
Operating Manual
Vertex Standard Co., Ltd.
47
selectivity on the order of a few dozen kHz at -6 dB, at the expense of a few dB of
system gain on bands where noise figure is seldom an issue. You will notice that
the S-meter deflection, when µ-Tune is engaged, is slightly less than when it is out
of the circuit; this is normal. If your antenna system gain is so low as to make it
impossible to hear band noise when µ-Tune is engaged (highly unlikely), just
switch it out, which has slightly less insertion loss.
As you tune around on an amateur band with µ-Tune engaged, the microprocessor
automatically commands the stepper motor driving the toroid core stack to center
the filter on your current operating frequency. You may, however, use the
[SELECT(µ-TUNE)] knob to skew the filter response to one side or the other from
your operating frequency, to deal with heavy interference on one side. To re-center
the µ-Tune filter on your operating frequency, and eliminate any offset, press the
[CLEAR] button.
Quick Note: The permeability-tuning concept utilized in the µ-Tune circuit dates back
many decades, as it was incorporated in such classic transceivers as the FT-101 and
FT-901 series, in addition to the FT DX 400 and similar models. The µ-Tuning Kit uses
a same circuit of our flag ship model FTDX9000 which is the highest development of
this circuit concept ever employed in an Amateur transceiver.
IPO (Intercept Point Optimization)
The IPO feature allows the operator to optimize the characteristics of the receiver front
end, depending on the current noise level and the strength of incoming signals.
Press the [IPO] button several times to set the desired characteristic of the receiver
front end, per the chart below.
AMP1: Amplifies the incoming signal path using a low distortion RF preamplifier
(gain: approx. 10 dB).
AMP2: Amplifies the incoming signal path using a 2-stage low-distortion RF
preamplifier (total gain: approx. 17 dB).
ON:
Bypasses the RF preamplifier, yielding direct feed to the first mixer.
The selected receiver RF preamplifier will be indicated in the IPO column of the Block
Diagram Display on the display.
Advice:
The IPO selection will be memorized independently on each VFO stack of the
