Usable Transceivers; Operation - Mat-Tuner mAT-125E Instruction Manual

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MAT-TUNER

USABLE TRANSCEIVERS

Most HF transceivers can use mAT-125E. They only need to satisfy two conditions: the RF
power level can be adjusted below 20 W, and they have at least one of AM, FM, CW, FSK, RTTY
modes to output constant carrier.
It should be noted that in the tuning process, a larger VSWR can be detected by the
transceiver. Because the output power of the transceiver is very low, this high VSWR should not
damage the transceiver.
power levels and they may turn off the transmitting carrier, which will cause the tuning to stop.
Yaesu transceivers are particularly susceptible to this issue. For Yaesu, the mAT-30 tuner will not
cause the radio to stop transmitting in the presence of higher VSWR while tuning, even at low
power output.
INSTALLATION
1. Connect the HF/50 MHz antenna jack on the transceiver to the "RF IN" jack on the back of
the mAT-125E, using a 50 ohm coax cable rated 120 watts or greater.
2. Connect the antenna feedline coax to the "ANTENNA" jack on the rear of the mAT-125E.
3. Grounding the mAT-125E tuner will enhance its performance and safety. We recommend
that you connect your tuner to a suitable ground; a common ground rod connected to buried
radials is preferred, but a single ground rod or a cold water pipe can also be used. We strongly
recommend the use of a properly installed, high quality lightning arrestor on all antenna cables

OPERATION

As with other general tuners, a constant RF signal of 1-20 watts power level is needed to be
present at the tuner input during the tuning cycle. This signal should be CW, FM, FSK, or RTTY.
The power level of the input RF signal must not be greater than 20 watts, otherwise it will shorten
the life of the tuning cycle, and the tuner can be damaged.
The mAT-125E ha two modes of operation: automatic and semi-automatic. Users can easily
switch between the two modes of work by using multi-function combination buttons.
Automatic Mode: When the RF signal is input into the mAT-125E, the tuner verifies that the
power at its input (FORWARD) is within the predefined range (1-20W). Power above this range
can damage the relays due to hot switching, while power below the predefined range can cause
inaccurate tuning. If the tune power is within the specified range, the tuner captures a 20ms
sample of the signal. The sample signal frequency is divided by 128 and measured by a counter.
The tuner reads the tuning data corresponding to the measured frequency from its internal memory
(such data exists if tuning was previously performed for this frequency). The tuner sets the tuning
network according to that data and measures the resulting VSWR, and displays the current VSWR
by the LED of the front panel. Even if SWR is higher than 2:1 the tuning cycle will not be
activated unless the TUNE key is pressed and released.
Semi-automatic: When the RF signal is input into the mAT-125E, the tuner only measures the
current VSWR and displays the results through the LED on the front panel. A tuning cycle is not
initiated until the [TUNE] key is pressed. When the [TUNE] key is pressed and released, similar
to the automatic mode, the tuner measures the frequency of the input signal, reads the
configuration data from the corresponding memory, and configures the LC tuning network. After
completing the above operation, the tuner will measure the current VSWR. If VSWR<1.5,the
tuning is completed. If it is higher, a new tuning cycle is started. When the tuner completes the
tuning process it stores the tuning network data in memory in a location corresponding to the
current frequency.
Some transceivers are very sensitive to this high VSWR even at low
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Instruction Manual