Coils and cristals.
See also "Setup".
Details of the ferrite antenna.
L102 : 2x7turns 1mm dia insulated wire, bifilar wound on a Conrad 8x50mm rod . Nominal inductance : 8.0 uH. For adjustment see "Setup".
L101 : 3 turns on the center of the ferrite rod.
Local oscillator coil L2 :
Standard Neosid 7.5 x 7.5mm RM2.25. 1.00 uH nominal,
Order at www.box73.de : filter spule BV5048 .
REM: pinning, see PCB and schematic !
In order to achieve correct tracking between the oscillator and antenna circuits, the self inductance of L2 MUST (once) be pre-adjusted correctly. !! DO NOT re-adjust L2 afterwards !! but tune with C110.
Adjustment of local oscillatorcoil L2 :
Before installing, adjust L2 with the help of a dipper :
L2 should resonate at 13.0 MHz with a 150pF 1% test capacitor in parallel to pins 1 and 5.
Then lock the core, it must NOT be retuned. L2 is now adjusted to 1.0 uH nominal. Use C110 to tune the oscillator to 14,190 MHz with the tuning knob set to minimum frequency.
L3,6 : 5 uH, 7.5 x 7.5mm RM2.25, start 1, end 5.
Standard Neosid coil. Order at www.box73.de : filterspule BV5056
REM: pinning, see PCB!
REM: the honeycomb wound Neosid SD75 type coils have higher inductance for the wanted SRF than axial wound chokes.
L7,10,12 22uH: standard Neosid radial choke RM5, SD75 22uH RM5 (Serial
Resonance Frequemcy >= 11MHz)
Conrad orderNr 535389
Or use 7x3mm axial choke 10uH.
L11 68uH : Neosid radial choke RM5, SD75 (SRF ca. 10MHz).
Conrad orderNr 535400
Or use 7x3mm axial choke 22uH.
L13,14,15,101 : 10uH 10 uH axial choke (RM7.5) Epcos 7x3mm
Conrad orderNr 501881
Order at www.box73.de : "Ferrit Dämpfungs perlen"
One-hole, small ferrite bead ca. 4x3mm.
REM: affix the bead with glue to the wire, or to the PCB, to prevent shaking and an instable local oscillator.
FB2 and FB5 also can be a vertically mounted resistor of 1k, the short wire connected to gate2, the long wire connected to the 22n cap.
FB6-9 can be a small toroid.
Xtalfilter F1+2: Order at www.box73.de : "quartz filter" 10M12B.
For this filter Rx=1k5. Ry=3k0 (3k3 // 33k).
Carrier Xtal Cr:
Order at www.box73.de (or at labelec.be) : "quartz" 10.7MHz HC18U
Solder the metal can quickly to mass at the point near R14. (This secures it, prevents hand effect and radiation).