Components List Of The Simple VHF Receiver Projects

 

Components List For LM380 Audio Power Amplifier, Suitable For Both Versions Of This VHF Receiver Circuits. The Audio Power Amplifier Must Be Constructed And Tested First

Resistors. All 1/4 Watt cracked carbon

R1 10K.

RV1 Volume Control 47K Log Pot.

Capacitors

C1 47NF Ceramic disc.

C2 4.7NF Disc Ceramic disc.

C3 220uf 25V Electrolytic.

C4 1000uf 25V Electrolytic.

C5 100NF Ceramic disc.

IC1

LM380N.

14 Pin dill socket for IC1.

Speaker

8 Ohm 250mw minimum.

RFC 1 VHF RF Choke 4.7uh NB. May not be needed, See text.

Components List For The Simple VHF Superregenerative Receiver

Resistors. All 1/4 Watt Cracked carbon

R1 R2 220R.

R3 4k7 If TR1 FET is BF244B or 1K when using a 2N3819 FET.

R4 R9 4K7.

R5 15K.

R6 150K.

R7 470K.

R8 6K8

R10 2K2.

RV1 Regeneration Control 10K Lin pot.

RV2 Audio gain control 100K Lin preset.

Capacitors

C1 2.2NF Ceramic disc.

C2 C4 1NF Ceramic disc.

C3 C5 10PF Ceramic disc.

C6 4.7NF Ceramic disc.

C7 10NF Ceramic disc.

C8 C13 C14 100NF Ceramic disc.

C9 C10 C15 100uf 25V Electrolytic.

C12 1000uf 25V Electrolytic.

VC1 25PF Air Spaced Variable. NB. Available from the following link Jackson Brothers - Variable Capacitors and Drives and the description is Type CO9 Trimmer Code C8O9A25. As this is a made to order item allow at least 1 to 2 Months for delivery.

TC1 5-15 PF Trimmer Capacitor

Inductors

L1 6mm Shower Cable Strands or 18 SWG Tinned copper wire.

RFC1 RFC2 4.7uh VHF choke. RFC3 Note that this item is hand wound. See text for full details.

Semiconductors

TR1 2N3819 FET.

TR2 2N3819 or preferably BF244B available at the time of writing from the following link Cricklewood Electronics

TR3 BC548 NPN Silicon Transistor.

Please note that that except for the VC1 25PF tuning capacitor and the BF244B VHF FET Transistor the following link Maplin Electronics has all the active components to build this receiver. All miscellaneous such as case batteries and hardware will be listed in a separate section below this heading.   

Components List For The Pulse Counting FM Receiver

Resistors. All 1/4 Watt cracked carbon

R1 R2 220R.

R3 4K7 If TR2 is BF244B or 1K when using 2N3819 FET Transistor.

RX 1K. NB May not be needed but its purpose helps stabilise the oscillator Regeneration control particularly when using BF244B in the TR2 position. 

R4 R16 R23 4K7.

R5 R22 2K2.

R6 R8 R10 R13 1M.

R7 R9 R11 33K.

R12 82K or if you want to include an IF gain control replace with 100K Lin Pot.

R14 R15 10K.

R17 R18 47K.

R19 150K.

R20 470K.

R21 6K8.

RV1 Regeneration control 10K Lin Pot.

RV2 Audio gain control 100K Lin Preset.

Capacitors

C1 2.2NF Ceramic disc.

C2 C4 C7 1N Ceramic disc.

C3 10PF Ceramic disc.

C5 5 or 10PF Ceramic disc

C6 4.7NF Ceramic disc.

C8 C9 C10 C11 470PF Ceramic disc.

C12 C14 C20 C21 C25 100uf 25V Electrolytic.

C13 C15 C19 C22 C24 100NF Ceramic disc.

C16 22PF Ceramic disc.

C17 1000PF when configured as a normal Mono receiver or 100PF Ceramic disc if you intend to experiment with a stereo decoder.

C18 100PF Ceramic disc.

C24 1000uf 25V Electrolytic.

VC1 25PF Air spaced variable capacitor available from the following link Jackson Brothers - Variable Capacitors and Drives and is a type CO9 Trimmer, Code C809A25

TC2 10 to 15PF Trimmer capacitor.

Inductors

L1 Made from the copper strands of 6mm shower cable or 18 SWG tinned copper wire.

RFC1 RFC2 4.7uh VHF Choke.

RFC3 This is a home made item and its construction details are explained in the main text.

Semiconductors

Tr1 2N3819 FET transistor.

TR2 2N3819 FET transistor or preferably BF244B available from the following link Cricklewood Electronics

TR3 TR4 TR5 TR6 TR7 BC548 Silicon Transistor NB. The AF preamp transistor is mistaken as a duplicate TR6 in the circuit diagram but is TR7. D1 D2 OA90 or OA91 Germanium Diode.

Apart from the items mentioned all components at the time of writing are available from the following link Maplin Electronics  

Miscellaneous Items for all VHF Receiver projects

Batteries

6 AA Size Alkaline type or 9V PP3 when used without AF Power amplifier as a tuner only. 

6 AA Size Battery holder.

Aluminium Case

The recommended case for housing both receivers is available from the following link Maplin Electronics  code KR56L.

75 Ohm Coaxial Antenna socket and plug. Single or double pole on/off switch.

6 section swivel base telescopic antenna available from the following link Maplin Electronics code YT20W. NB. You will need some sort of isolation from the aluminium case which can be achieved by adapting a suitable BNC plug and socket on the receiver to fit. Also an alternative and better bet, But a bit more expensive is the 10 section telescopic antenna which has a  BNC connector fitted is available from the following link Maplin Electronics and covers the whole VHF and UHF range between 30.0 MHZ - 13000 MHZ.  

Other Items

The other items such as knobs bolts and washers I will leave up to you to decide although I do not recommend the use of unleaded solder as I have learned you do not get a very clean shiny joint as you do when using leaded solder. Screened cable is also recommended for all audio connections to volume control and auxiliary output sockets.

Back To-Progressive Crystal Set To Regenerative Receiver Using Safe 12V HT Line