Vectronics VEC-821K, Руководство пользователя

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VEC-821K Instruction Manual Super CW Filter Kit
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generator and oscilloscope. However, VEC-821K does not require any
alignment. If all components are installed correctly and in the proper
places, the center frequency of the filter will be between 750-800 hertz.
The filter has three switch selectable selectivity cutoff points, 80, 110, and
180 hertz. The switch positions on SW1 from left to right are BYPASS,
180, 110, and 80. The 80 hertz cutoff is the fourth switch position from
the left and is the narrowest filter cutoff, while the 180 hertz cutoff is the
second position from the left and is the widest filter cutoff.
Probably the best method of seeing if the VEC-821K is working, or not, is
to listen to some "
on the air " CW signals. Then using SW1, select the
filter cutoff position that best cleans up the signal being received.
If you are trying the pick out one signal out of a very tight band pile up,
then try using the 80 hertz cutoff. The 80 hertz cutoff provides the
highest selectivity and will greatly help you in "pulling out" those hard to
get signals.
If the CW signal you are receiving is noisy with some static, then try
either the 110 or 180 filter cutoffs. However, in these positions the filter
will let slightly more noise through, but in some cases this may be
desirable. The best way to see which position works the best is to try it.
This way you can really hear what the filter is doing for the received
signal, and which switch position works the best in different band
conditions.
OPERATING INSTRUCTIONS
You may use the VEC-821K with any communications receiver or
scanner with a BFO, (Beat Frequency Oscillator). You can also use the
VEC-821K with and ham-radio transceiver in either LSB or CW mode.
The VEC-821K requires a 9-volt battery power source, or any 9-18 volt
DC source.
There are a few items that you will need to operate the VEC-821K. We
have provided a list of these items below for your convience.
Communications Receiver, scanner, or Ham Radio transceiver with
proper cables.
9-Volt transistor radio battery
External speaker with clip leads
Receiver or Scanner Operation
As previously mentioned you can use the VEC-821K with a
communications receiver or scanner. A BFO, or Beat Frequency
Oscillator, or a Fine Tuning control will assist you in fine tuning the
received CW signal to the VEC-821K center frequency. The center
frequency of the filter being 750-800 hertz.
The filter requires audio from the external speaker or headphones output
of the receiver or scanner. Apply the positive side of the audio signal to