QRPproject DL-QRP-AG, Manual

Page: 20 / 53

Version: 13. Sepe
,m
er 2004
20
Section 6 BFO, IF amplifier, AGC
[ ] IC9 Socket 16 PIN A/B3
If you install the IC now, be very carefully. All IC pins must go
straight into the corresponding part of the socket. Dont bent
the IC pins. Discharge yourself before you handle the IC.
[ ] IC9 TCA440/A244 DIL16 A/B3
[ ] IC10 TDA7050 DIL8 B/C2
[ ] D23 1N4148 B2
The following germanium diodes have quite sensitive, large
glass bodies. The raster on the pc board is too small for them
to be mounted horizontally. All 4 diodes should be mounted
obliquely.
[ ] D24 AA143 or the like C2
[ ] D25 AA143 or the like C2
[ ] D26 AA143 or the like C2
[ ] D27 AA143 or the like C2
[ ] T16 BC337-40 B2
[ ] C93 1000pF RM 5mm A3
[ ] C94 10nF 103 A3
[ ] C95 22nF 223 B3
[ ] C96 10nF 103 B3
[ ] C98 100µF/16V rad. A4
[ ] C99 100nF RM 5mm A3
[ ] C100 22nF 223 A4
Remember to polarize the tantalum capacitors correctly. The
long wire is PLUS.
[ ] C101 10µF/16V Tantalum pearl A/B4
[ ] C102 1µF/35V Tantalum pearl B4
[ ] C104 10µF/16V Tantalum pearl B4
Mount the electrolytic capacitors correctly. The long lead is PLUS.
[ ] C103 33µF/16V radial B4
[ ] C107 10µF/35V radial B/C2
[ ] C108 10µF/35V radial B2
[ ] C109 47µF/35V radial C2
[ ] C105 0,1µF Film RM 5mm B3
[ ] C106 0,033µF Film RM 5mm B3
[ ] C110 0,1µF Film RM 5mm C1/2
[ ] R70 120R B3
[ ] R71 2,2K A4
[ ] R72 100k B4
[X] R73 27R SMD 1206 B3
[ ] R74 560R B3
[ ] R75 18K B3
[ ] R76 470R C2
[ ] R77 470R C2
[ ] R78 27K C2
[ ] R81 33K B2
[ ] R82 12K B2
[ ] P5 2k5 PT6 lying B3
[ ] PIN20 B4
[ ] PIN25 B2
[ ] PIN26 B1/2
[ ] PIN27 B1
As shown in the wiring plan (see schematic section of the manual) you
must solder a 100nf (104) cap and a 1k0 resistor between pin 20 and
ground. Solder at the solder side of the PCB.be carefull not to short any
other tracks.
[ ] 100n
104
[ ] 1k0
To test this section, we need the link to the AF amplifier. Prepare the
volume potentiometer (2k2 log). Logarithmic potentiometers are identified