Kanga Products Bassinet, Manual And User Manual

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Rooster CW Transceiver Rev3 Page 21 of 26 22
nd
Nov 2023
seen between units, this variation will only be 1dB or so and will not be noticeable to anyone
receiving your signal.
Current draw will be around 20mA on RX, and 400mA TX (@12v)
Now connect the Rooster to an antenna. If nothing else you will hear band noise.
Adjust the RIT to vertical and call CQ, if called back adjust the RIT for best reception and enjoy the
QSO.
Notes
All direct conversion type receivers can suffer from noise and other issues when used with a mains
power supply. We recommend that the Rooster is powered by a battery pack. We have used and
would recommend a 3-cell lithium-ion battery pack that gives just over 11v. the Rooster still
produces around 1.5 watts at this voltage and will operated for a very long time with such a power
pack. A 7Amp/Hr 12v lead acid battery is also a good choice.
Other 40m band frequencies can be used by changing the Crystals, if you are only moving by a
couple of KHz then you will be ok just changing the mixer crystal (Y1) if more then you will need to
change all three crystals to the same frequency.
Audio Filter Response
The Rooster unlike many such simple transceivers uses an active audio filter, the filter makes use of
the spare op-amp in the dual op-amp used in
the audio amplifier. This is centred around
750Hz and has a bandwidth of 500Hz.
The filter is certainly NOT a brickwall but
does give a useful peak of about 12db to its
centre frequency, here is a waterfall showing
the filters response. We used a Kanga RF
Noise source module for the input to the
transceiver and used a waterfall display to
see the response.
The Rooster, as you would expect has a LPF on its output . We have included 2
nd
and 3
rd
Harmonic
traps too. Here is an example of the RF output spectrum, this was supplied by one of the Beta
builders at the RSGB Convention.
We hope you
enjoy building
and using the
Rooster. Any
questions or
comments to
sales@kanga-
products.co.uk