QRP PROJECT Blue Cool Radio, Руководство пользователя

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Rev:Nobember 20. 2006
15
every quartz, cleaning with a glass brush or similar tool makes soldering at
the Quartz housing easier.
[ ] Quarzhousings to ground.
[ ] R25 6,8K supright D-4
[ ] C8 150pF COG (150p or 151) D-4
[ ] R6 56K upright D-5
[ ] C12 47nF (473) C/D-5
[ ] R7 56K upright D-5
[ ] C10 150pF (150p or 151) D-4/5
[ ] P6 10K Potentiometer SMC-10-V C/D-4
The following diodes do not have the standard glas or plastic housing but
are built into a TP92 Transistor housing. They look exactly like a little
transistor with only 2 legs plus a very short 3rd leg in the middle. If you
install it, take care to leave a little distance between the PCB and the short
3rd leg to avoit shortening the two solder pads.
[ ] D8 BB112 D/E-5
[ ] D9 BB112 D/E-5
Attention, Transistors are ESD sensitive.
[ ] T11
BF199 E-3
[ ] T2 BF244B D/E-4
Now another coil. L3 which is very similar to the others:
Resonate winding: 18 turns 0,1mm laquered wire between PIN 2 and PIN 1
Coupling winding 4 turns 0,1mm laquered wire between PIN 4 and PIN 3
[ ] L3
Neosid 7.1 F10b D-4
You now may install the IC into their sockets. Don´t interchange them,
apply the notch to the correct side (according to the placement plans, both
nothes look to the right side.
ATTENTION: remeber ESD rules!!
[ ] IC1 74HC04 D/E-3
[ ] IC2 74HC4066 D/E-3/4
All ok? Dont forget to recheck your work with a magnifier. Please do not let
out this step. OK, I know you are doing a good job here, but > 90 % of kits
I get for support fail due to soldering failures!
The BCR Receiver now is nearly complete. AF and IF are ready installed, the
mixer is on board, only stage missing to be ready to receive signals is the
„Frontend“ with Preselector and Low Pass filter. However, you can test the
complete IF part now. The link we used in the section before this time is
not needed because the Mixer does a direct connection between IF and DDS
Generator.
As you know, the BCR RX and TX frequency are generated in a different way:
in TX mode the DDS VFO is working directly on the end frequency, in RX
mode the DDS is shifted by the IF frequency. To make the RX listening on
the correct frequency, the IF frequency mut be known exactly to the PIC to
calculate the shift. The middle frequency of Ladderfilters in principle is
somewhat lower the the frequency of a single Quartz. With the help of the
integrated IF generator, we now must find the individual middle frequency
of your BCR.
Attach the headphones and powersupply.
Attach a Voltmeter at the upper end of R14. (If you own an needle
instriment, use it. A Digital Voltmeters will do the job also, but with a
needle Voltmeter it´s more comfortable because you better see tendencies
while adjusting).
• Adjust the ferrite caps of L3, L4, L5. The upper end of the cap should be
abt 1-2 mm below the copper can.
• Switch S1 to SSB ( toward Display = AM )
• Adjust C29 to it´s half capacity position (you can see the plates through
the foil)
• Switch on your BCR.
• Adjust P6 counterclockwise to its end, then back abt 10 degrees clockwi-
se.
• Adjust P5 to about 200mV at R14. Switch to AM. You will see a diffe-
rent, lower reading. The difference should not exceed 100mV. Leave the
switch in AM position.
• Go to Menu, Setup, ZF. The display shows the actual generated IF fre-
quency. Your Voltmeter should read more or less increased Voltage now.