After mechanical installation is complete select the highest frequency to be used on the
transceiver. A directional watt meter such as a Bird Model 43 should be inserted in the
coaxial transmission line between the transceiver and the tuner. The tune mode on the
transceiver is then energised (refer to the transceiver user manual). Upon application of RF
energy, the tuner should start to tune, indicated by the 'clattering' of the tuner relays. After a
few seconds the relay noise will cease. The transceiver should indicate a successful tune
and the watt meter reflected power should indicate a low value consistent with a VSWR of
better than 2:1. If the cover of the tuner is removed the PCB mounted 'tuned' LED should
be illuminated. Now select the lowest desired frequency on the transceiver and repeat the
above procedure. The result should be the same, except that the tune cycle may take
somewhat longer. If the above procedure does not give the results as indicated check that
the antenna length and connections are correct and re-check all ground (earth) connections.
Electrical checkout
Note:-
When received, the Barrett 911 automatic antenna tuner memory system will
usually not have any pre-stored tuning information appropriate to your
installation. To allow the 911 to 'learn' its tuning information simply proceed
from one channel to the next allowing the normal tune cycle to take place.
Each successful tune is 'memorised' so that when that channel is re-
selected the tuner will almost instantaneously retune to that frequency.
BARRETT 950 HF TRANSCEIVER
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