4 Metre Product List,      Prices Inc UK Carriage unless otherwise stated.

Contents

Station Receive Preamps

Masthead Receive Preamps  Masthead fitting kit available for both types.

Transverters Probably the best selling Transverter in the World

Transmit Amplifiers 

Mellstock 2 channel 1W AM Transmitter

Mellstock 2 channel AM Receiver

Receive Converters

Portland VFO for 40m or 4m

Mixer - Osc for 4 metres

Poundbury SSB Generator & Receive IF   

Poundbury 70MHz Front end mixers and amplifiers   

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STATION RECEIVE PREAMPS for 4 metres. 100W through rated on transmit. RF & DC switched 0-20dB panel adjustable gain. 4m type uses BF964 with noise figure under 1.5dB. 1Over-voltage and reverse voltage protected.   Protected against transients and EMP at input and output ports. PCB size 68 x 46 x 28mm. Purpose made box 76 x 70 x 38mm. Fitted with SO239 connectors. DC supply 13.5V 80mA. Type RP4S. PCB Kit £15.00, PCB Built £26.00, PCB & hardware kit £29.00, Boxed Built £47.00.

MASTHEAD RECEIVE PREAMPS for 4 metres. 100W through rated on transmit. RF & DC switched and DC fed via the coax. Gain 20dB, NF less than 1.5dB. Supplied with a DC to RF Station Box with SO239 connectors for the shack. Heavy duty waterproof plastic box fitted with SO239 connector for feed coax and 1 metre of coax for connection to the antenna. Box size 82 x 80 x 50mm. Type RP4SM. PCB & hardware kit £38.00, Ready Built £57.00.  Masthead fitting kit £6.00.

MASTHEAD RECEIVE PREAMPS for 4 metres.  400W through rated on transmit. RF switched. Supplied via separate wire DC feed.   Gain 20dB, NF less than 1.5dB.  Protected against reverse and over voltage and against EMC transients at input and output. Heavy duty waterproof box fitted with SO239 connector for feed line and 1 metre of coax to connect to antenna feed point. Box size 82 x 80 x 50mm. Type RP4SH.  PCB & hardware kit £40.00,  Ready built £62.00.  Masthead fitting kit £6.00.

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TRANSVERTERS   Early commercial transceivers often had a transverter facility with low level output from the early transmit stages and a means of disabling the power amplifier stage.  This meant there were dual connections for an outboard transverter, one from the low drive transmit port and the other for receive using the main antenna socket.  Some top of the range rigs still have this feature but most modern rigs don't have any transverter facility.   To use them you simply reduce the power output from the rig to as low as possible and use a single connection to the transverter from the antenna socket.  The RF sensing in the transverter then looks after RX/TX  switching.

Transverters are available to add 4 metres to a rig with 10 metres or with 2 metres.   The transverter main board contains an attenuator in the transmit path and can be configured for 1-500mW or 0.5-10W drive levels. Class AB linear operation gives all mode use.   The standard product includes a linear amplifier giving panel adjustable output 5 to 20W on 2m, or 5 to 25W on 4 or 6m..  All spurious and harmonic outputs better than 50dB below carrier.  Capable of withstanding long periods of transmit into bad SWR.  Receive side has panel adjustable gain 0-20dB gain and NF less than 1.5dB.   PCB size 150 x 93 x 18mm.     Box size 206 x 160 x 77mm. Type TRC4-10 or TRC4-2. Suffix 's' is used for single IF drive arrangement, suffix 'd' is used for dual IF drive version, the suffix 'L' is for the integral linear.

Transverters giving 0.5W output for use with 10 metre or 2metre rig with a single connection and 0.5-10W drive.  TRC4-10s, TRC4-2s. PCB Kit £60.00, PCB built £91.00, Box kit £95.00, Boxed built £140.00.

Transverters giving 0.5 W output for use with a 10 metre rig with dual transverter connection and 1mW-500mW drive.  TRC4-10d. PCB Kit £60.00, PCB built £91.00, Box kit £95.00, Boxed built £140.00.

Transverters giving 25W output for use with 10 metre or 2 metre rig with a single connection and 0.5-10W drive.  TRC4-10sL, TRC4-2sL. PCB kit £130.50, PCB built £174.00, Box kit £163.00, Boxed built £244.00.

Transverters giving 25W output for use with a 10 metre rig with dual transverter connection and 1mW-500mW drive,  TRC4-10dL. PCB kit £130.50, PCB built £174.00, Box kit £163.00, Boxed built £244.00.

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TRANSMIT AMPLIFIER for use with Spectrum 0.5W Transverters. Two stage PTT switched class AB linear amplifiers for 4 metres giving a minimum of 20W out, and a maximum of 35W. Antenna relay with high speed TX/RX switching makes it suitable for all modes including data and RTTY and Packet. PCB size 125 x 57 x 28mm. Types TA4S4,    PCB kit £70.50, PCB Built £83.00.

TRANSMIT AMPLIFIER Single stage switched class AB linear amplifier suitable for CW, SSB, FM, RTTY, and PACKET. Versions for drive levels of 1W-5W and output levels of 8W-30W. Switching circuit senses RF & DC and uses a monostable relay driver giving VERY FAST attack and a hold time of 250ms to 2s for SSB use. For data modes the hold function can be disabled. PCB size 102 x 71 x 17mm. Diecast box size 127 x 102 x 38mm. Fitted with SO239 connectors. Type TA4SA. PCB Kit £46.00, PCB built £60.00, PCB & hardware Kit £59.00, Ready Built £82.00.

TRANSMIT AMPLIFIER Single stage switched class AB linear amplifier suitable for CW, SSB, FM, RTTY, and PACKET. Versions for drive levels of 5W-20W and output levels of 22W-60W. Switching circuit senses RF & DC and uses a monostable relay driver giving VERY FAST attack and a hold time of 250ms to 2s for SSB use. For data modes the hold function can be disabled. PCB size 102 x 71 x 17mm. Diecast box size 171 x 120 x 55mm with a heatsink on top 152 x 99 x 32mm. Fitted with SO239 connectors. Type TA4SB. PCB & hardware Kit £65.00, Ready Built £88.00.

TRANSMIT AMPLIFIER & PREAMP.  The amplifiers described above and a matching preamp RP4S  together in one box with independent switching. 1W-5W in 8W-30W out, together with 20/26dB gain preamp. Types TA/RP4SA. PCB & hardware Kit £72.00. Ready Built £109.00.

TRANSMIT AMPLIFIER & PREAMP.  The amplifiers described above and a matching preamp RP4S  together in one box with independent switching. 5W-10W in 45W-60W out, together with 20/26dB gain preamp. Types TA/RP4SB.  PCB & hardware Kit £75.00. Ready Built £112.00.

TRANSMIT AMPLIFIER for 4 metres. 250mW to 500mW input, 20w to 35W output, with RF & DC switching. Class AB operation gives clean output with intermod products 35dB down suitable for all modes CW, SSB, FM, & DATA. Designed as self contained amplifier as an add-on for 0.5W transverters such as MEON. Boxed size 127 x 102 x 38mm. Type  TA4S2. PCB & hardware kit £80, Ready built £99.50.

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MELLSTOCK 1W AM 4 metre TX, a two channel transmitter with integral speech processor. PW Sept & Oct 2005. PCB £16.00. Mod Transformer £9.50. Crystals £8 the pair. PCB & component kit with crystals & transformer but without hardware £57.50. Complete kit with drilled and labelled box and other hardware £76.50.

MELLSTOCK 4 metre AM RX, a two channel receiver as a companion for the Mellstock TX. PW Nov 2005. PCB £10.00. Crystals £8 the pair. 100uA edgewise S meter £9.00. Components including volume pot and channel toggle switch but without crystals and S meter £31.00. Complete kit without meter £48.00. Complete kit with meter £57.00.

RECEIVE CONVERTERS add 4 metres to a receiver tuning 28-30MHz,  Type RC4-10 is low noise and has 15dB gain. This is a brand new design productionised in November 2001 incorporating a diode ring mixer together with an improved oscillator and multiplier circuit. The Boxed version has panel adjustable gain, on/off switch and power LED. Fitted with SO239 connectors and has 1metre of lead for 13.5V bench power input. PCB size 95 x 45 x 17mm, Box size 102 x 84 x 40mm.  Type RC4-10. PCB kit £29.00, PCB built £42.50, PCB & hardware kit £43.75, Ready built £69.50.

RECEIVE CONVERTERS add 4 metres receive to a 2 metre transceiver. These are low noise using a mosfet RF & mixer stage and have 15dB gain. The Boxed version has panel adjustable gain, on/off switch and power LED. Fitted with SO239 connectors and has 1metre of lead for 13.5V bench power input. PCB size 89 x 45 x 17mm, Box size 102 x 84 x 40mm. Types Types RC4-2. PCB Kit £25.00, PCB Built £38.00, PCB & hardware kit £40.00, Boxed Built £64.00.

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PORTLAND VFO, a rock stable FET VFO for 6.985 - 7.215MHz for a direct conversion for the extended 40metre band, or 7.900 - 8.400MHz for use as part of a mixer VFO system as local oscillator on 70.000 - 70.500MHz band.  PW project March 2006.  Supplied with Buffer 1 for low level mixers or Buffer 2 for high level drive mixers. PCB and component kit with potentiometer £15.75. Drilled Box and PCB kit with potentiometer and feedthroughs £24.00.  Ready built units £47.50. State required frequency when ordering. 

MIXER - OSCILLATOR, a module for use in conjunction with the Portland VFO to produce a very stable local oscillator signal for a 4 metre receiver or transmitter with a 9MHz or 10.7MHz IF. Uses either a 51.4MHz crystal for a 10.7MHz IF, and a 53.1MHz crystal for a 9MHz IF. Comprises an overtone oscillator, a 4 quadrant multiplier mixer, a filter and buffer amplifier. PCB kit including choice of crystal £24.00. Ready built £34.75.

POUNDBURY 9/10.7MHZ SSB Generator and Receive IF. A traditional SSB generator incorporating a speech processor and diode ring balanced modulator and 6 pole crystal filter. Carrier suppression typically in excess of 50dB. The board now connects directly to the SSB filter which has a termination impedance of around 500 ohms and a few picofarads. Other termination impedances can be accommodated by the change of a single resistor. The circuit has provision for just one parallel mode carrier crystal. Receive section uses Fet and Mosfet IF amplifiers and a singly balanced diode product detector and discrete audio derived AGC. Includes 1W audio amplifier. A 6 pole crystal filter for 9MHz together with a carrier crystal to produce USB are included in the PCB kit.  PCB and component kit with filter and carrier crystal £80.00.  Optional extras, mic gain 4K7 log pot, volume 100K log pot, £1.75 each.  Signal meter £9.00.  8 ohm Loudspeaker £2.00.  P&P on optional extras £1.50.

POUNDBURY 70MHz FRONT END.  A receive preamp and mixer together with a transmit mixer and three amplifier stages to give 250mW output on 4 metres.  Works in conjunction with the Poundbury Generator & Receive IF, the Portland VFO, and the Mixer-VFO board to give a complete 4metre transceiver.  Can also work with the TA4S4 amplifier to give 25W output.  Front End Board PCB & Parts including 2 panel pots £44.00.

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