Components List Of The Crystal Set
Components List For Simple Basic Crystal Set
Resistors 0.5 Watt Cracked carbon
R1 100K. Colour code Brown Black Yellow
Tuning Capacitors And Trimmers
VC1/VC2 365PF available from 6V6 Vintage Radio & Audio Components . Also they have a wide range of other components such as miniature tuning capacitors which may work out cheaper in the long run, including the diodes.
D1 OA90 or OA91 Germanium Diode available from 6V6 Vintage Radio & Audio Components or Maplin Electronics
L1 Tuning Coil
20 Millimetre wooden dowel or plastic tube, available from most DIY shops or garden centres.
Wire for winding tuning coils
Medium Wave 550KHZ - 1600KHZ Coil 36 SWG enamelled copper wire.
Shortwave 1.5 - 4.5 MHZ Coil 26 SWG enamelled copper wire.
Shortwave 7.5 MHZ - 15.0 MHZ 20 SWG enamelled copper wire.
All available from Maplin Electronics
Must be high impedance type for this version or a crystal earpiece available from Maplin Electronics order code LB25C is suitable
Components List Of The Simple Basic Crystal Set Designed For Low Impedance Headphones or speaker
Components list is basically the same as the high impedance version but the following components that are not required is as follows.
R1 100K Resistor
High impedance crystal earpiece
Additional Components Required
100 Volt line matching transformer available from Maplin Electronics order code N35JB
8 or 16 Ohm types are suitable and if reception is very good, a speaker may work but don't expect miracles due to lack of audio amplification.
Components List For Voltage Doubler Crystal Set
Components list is basically the same as the low impedance version regarding the tuning capacitors and coils but the additional components that are required are as follows.
D1 and D2. OA90 or OA91 Germanium Diode
C1 and C2. 2200PF Ceramic Disc Capacitor, Code 222.
S1 Impedance load change over switch. Single pole rotary switch. Available from Maplin Electronics Code FF73Q. Note that if you intend to incorporate simple band switching, then this switch is also suitable so you may need to order 2 of them.
Tinned PVC copper wire for antenna and interwiring of various stages
Veroboard or wooden baseboard using cupped screws is suitable
Soldering Iron. 25 to 40 watt maximum preferably with 25V isolation isolation transformer. NB Children must be fully supervised by an adult at all times when using soldering apparatus for the safety reasons I have mentioned in the main article.
Multicore Resin type, preferably unleaded and needed for building the amplified version of the crystal set.
Vero Pins, for interconnecting wires on circuit board
Amplified Crystal Set Components List
Basically the same as the simple crystal set except the following component must be omitted.
High Impedance Crystal Earpiece. NB Leaving this component connected will allow the set to work as a miniature public address amplifier using the crystal earpiece as a microphone except due to loading of the amplifier input there will be reduced volume.
Although the R1 100K resistor is called out in the circuit and wiring diagram, this is also not required as the RV1 Volume control provides forward bias so ignore this component.
Additional Components Required
Resistors 0.5 Watt cracked carbon
R2 10K Brown Black Orange
RV1 47K Log pot
C1 and C2 47NF Ceramic disc Code 473
C3 220uf 25 Volt Electrolytic
C4 100NF Ceramic disc Code 103
C5 1000uf 25 Volt Electrolytic
IC1 LM380 Audio power amplifier, available from Maplin Electronics code QH40T
14 Pin DILL holder, available from Maplin Electronics code BL18U
S1 on/off Switch
Single Pole 1 Amp toggle switch
Batteries, Connectors And Holders
6 AA Size 1.5 V Alkaline.
PP3 Battery Connector, available from Maplin Electronics code L85AB
6 AA Size Battery Box, available from Maplin Electronics code HQ01B
Back to-Progressive Crystal Set To Regenerative Receiver Using Safe 12V HT Line