Quality English products hand-crafted to order

News & New Products - 15 December 2021

Proprietor;- Mr A.J. Nailer HNC BA G4CFY. 


Phone UK 01305 262250 International 0044 1305 262250

Please email or phone for a quote or for a Paypal money request or for bank details. Payment can be by direct bank transfer or by credit/debit card or via Paypal to g4cfy@spectrumcomms.co.uk  together with a note stating product required. Purchase of several items is likely to make a saving on postage. You can also obtain products by using my Ebay shop https://ebay.co.uk/str/Spectrum-Comms and pay via Paypal.

Orders, quotes & technical requests to  g4cfy@talktalk.net

NEWS & PRODUCT UPDATE 15 December 2021

Jean Nailer, my wife for 51 years and business partner in spectrum for 40 years passed away from a brain haemorrhage on 29 november 2021

There is lots to do and unfortunately these web pages are a long way down the list.
A number of products listed below have now been removed because they weren't selling.


The Spectrum website has undergone a long overdue revamp.  The Listener page has been amalgamated into the Receive & Transmit Boxed Products and Receive & Transmit PCB Products pages. Some products that haven't sold for ages have been removed and no doubt you won't even notice.  Other products that have been on my Ebay shop site for much of the year are now included in the appropriate pages. At the bottom of the page are details about Understanding Radio Book 1 & Book 2.  To assist the searcher the content of each of the other Spectrum pages now include the contents.


Coax cables Balun 1-42MHz Air cored (RX & TX) Active Wire Aerial (RX)
95 Ohm Twin Feeder Slim-G VHF (RX & TX) Nomad VHF/UHF (RX)
G4CFY Traps Flexi-whips VHF/UHF (RX & TX)  Active Nomad VHF/UHF (RX)
G4CFY HF Trap dipoles (RX& TX) Mobile Whip Aerials VHF/UHF (RX/TX) Compact Coil HF Active Aerial (RX)
Inverted-L HF (RX & TX )  G4CFY Aerial Development History Long Wire HF portable aerial (RX)


Piptone, Kaytone Frequency mod-demod, FM455 VCO48 block for Cybernet 048
Spectra bleedover filter, SF10.7 Speech Processor, SP059 EU and UK add-ons for FM rigs
Noise Squelch VCO27 block for Cybernet 059 & 121 UK add-on for multimode rigs


PTFE Feedthroughs Ferrite Binocular core Field Effect Transistors, junction type
Polyvaricon Tuning Capacitors Ceramic 2 pole 5 way Switch Dual Gate Mosfets, 40673, 3N201, etc
Spectrum 10mm Coil (TOKO replacements) Power Relay IF Filters, crystal, ceramic, & ladder
Capacitors, fixed and trimcap Resistors, fixed and trimpot Crystals, new & S/H, HC18U, HC49U, etc
Dust Iron Toroidal Cores Diodes, signal, varicap, zener, rectifier Integrated Circuit, Op Amps, & RF/IF, etc
Ferrite Toroidal Cores Transistors, small signal, AF, IF, RF power Valves, B7G, B9A, & Octal


RX L-TYPE ATU VHF Masthead Preamps RF Switched
RX SPC ATU 100kHz to 4MHz Receive Converter
QRP TX SPC ATU VLF/LF to 4MHz Receive converter
HF Tuneable Preamp 1.8-30MHz VHF Receive converters 2m, 4m, & 6m
HF Switched Preamp 1.8-30MHz Clara 2 Receiver
VHF Receive Preamp Transverters 2m, 4m, & 6m
110-400MHz Scanner Preamp VHF Transmit Amplifiers, 25/50/100W
VHF Station Preamps RF Switched 4001 FM 4m Transceiver


Intermediate Licence VFO RX Mixer & Dual Front-end BP Filters Regen Receiver, single band
Intermediate Licence Crystal Oscillator SSB IF Filter 6-Pole, 9 or 10.7MHz Regen Receiver, four band
Portland VFO v2 RX 9MHz IF Amplifier with AGC Super Sudden by G3TEX & G4CFY
5 Band 100W TX Low Pass Filter SSB Detector & CIO 9 or 10.7MHz Piptone PT1000S
5W Broadband HF Linear SSB Detector & CIO 455kHz Kaytone KT2000
RX Front-end Filters, 5 & 10 band Audio 500mW Amplifier CTCSS Encoder


High Pass TVI Filter 175MHz Capacitance Meter, 1pF to 10uF Two Tone Tester, for transmitter alignment
High Pass TVI Filters 450 & 550MHz Peak Envelope Power module Crystal Calibrator, for receiver alignment
Coax Cable Tester HF Wide Range Power Meter Morse Oscillator


Understanding Radio Book 1 is a re-write of the Technical for the Terrified Book 1 published by Practical Wireless and compiled from 27 articles of that name previously published in PW Magazine between February 2005 and October 2008. The first chapter is a short revision for everyone who has not used algebra since leaving secondary or grammar school.  It should also be useful to youngsters still at school and trying to get to grips with it.  The articles have been reworked into chapters so there is now a natural progression of information through the book.  All the circuits have been redone and a lot of wasted space and unnecessary comments removed.  It runs to 112 pages, which is 10 less than the T4T Book 1 but there is a lot more in it.  The writing style is aimed to be easy to read and should be of great value to readers of all technical levels.   Subjects include; Algebra; Resistors & Ohm's Law; Diodes and Rectification; Transistors - FETs & Valves; Transistor biasing; Amplifier Classes of Operation; Reactance & Resonance; Parallel Tuned Circuits; Bandpass Coupled Pairs; Small Signal Bipolar RF/IF Amplifiers; Small signal FET & Mosfet RF/IF Amplifiers; Oscillators; Mixers; Decibels; Modulation Modes; TRF & Superhet; Filtering in HF & VHF Receivers; Modes & Demodulation; Choosing RF - IF & LO; Phase Locked Loop; PLL in CB & 10M rigs; Antennas & Feeders.  

Understanding Radio Book 2 first print run was early June. It is a re-write of Technical for the Terrified Book 2 including all the articles 28-49 published in PW between October 2008 and April 2013 plus article 51 published in August 2013.  The articles have been condensed into chapters and unnecessary duplication of information has been trimmed back and then the subjects further expanded.  It runs to 114 pages and the subjects include Passive components, old and new; Equivalent circuits; Variable Frequency Oscillators; Crystal Controlled Oscillators; Feedback & Amplifier Stability; Singly Balanced Mixers; Analogue Low Pass Filters; Laying out Printed Circuit Boards; Measurements and Test Jigs; Receiving 100kHz - 30Mhz; Superhet Receivers; AGC of RF & IF Stages; Superhet with Tuneable IF; Coax & Twin Feeder; SWR/PWR Meters & the Noise Bridge; Aerial Impedance - Bandwidth & Gain; Aerials for Receive & Transmit; ATU's for Receive & Transmit.

To buy either book on its own including postage pay £15.50 to my personal Paypal account antony.nailer@talktalk.net or through Spectrum, or by direct transfer to my bank.

To buy both books together pay £29.00 to my personal Paypal account antony.nailer@talktalk.net or through spectrum, or direct transfer to my bank.

Spectrum Communications was established as a part-time business by Tony Nailer G4CFY in October 1978.  In August 1981 following the legalization of CB in the UK there was sufficient work and CB sales for both Tony & wife Jean for full time employment.  CB popularity declined steadily to a very low level by about 2000 and for the following 4 years sales were almost at unsustainable levels.  Following becoming an author with PW in 2004 and developing new projects for the Doing It By Design series, sales have risen back to make us busier than ever. I became author of another PW series In 2005 titled Technical For The Terrified. I ceased being an author in 2017 following the change of ownership of PW.

G2DYM Aerials was purchased from Richard Benham-Holman G2DYM on 30 October 2006.   

Garex Electronics was purchased from Peter Longhurst G3ZVI on 1 December 2011.