Flexi-whips can be custom manufactured for any frequency in the range 68-418MHz, and the 2m (144MHz) version is normally made and trimmed as a dual band, 144/433MHz aerial.
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SPECTRUM COMMUNICATIONS ESTABLISHED OCTOBER 1978. Proprietors;- Mr. A.J. Nailer HNC BA G4CFY, Mrs. J.R. Nailer. 12 WEATHERBURY WAY, DORCHESTER, DORSET, DT1 2EF, UK Phone & Fax UK 01305 262250 International 0044 1305 262250. Email tony@spectrumcomms.co.uk Garex Whip Aerials - 8 January 2012 Prices include postage & packing for UK and EU. All popular credit cards accepted, phone or email details. Make Cheque or Postal Order payable to Spectrum Communications. |
FLEXI-WHIP alternatives to short helical aerials.
Short helical 'rubber duck' aerials are compact and convenient but are poor performers. The reduction of gain is close to the square of the shortening factor. So on 4m as an example, if the full quarter-wave should be 1 metre long and the helical is only 12.5cm, the shortening factor is one eighth, so the reduction of gain will be about one sixty-fourth of a full size quarter-wave whip. In radio terms 1/64 is equivalent to -18dB.
The FLEXI-WHIP on 4 metres can be made 50cms long. The shortening factor is a half and the gain reduction is a quarter, or -6dB. Therefore the 50cm flexi-whip will provide about 12dB more gain than a 12.5cm helical.
| The GAREX FLEXI-WHIPS have a springy core with a
nylon cover which are sufficiently flexible but robust. Solutions have been
developed to allow the aerial to be supplied with a wide variety of plug or
socket connectors. The maximum production length is 50cm, so for
frequencies below 140MHz they are made as shortened loaded quarter-wave
aerials, and above that frequency they are full quarter-wavelengths.
Flexi-whips can be custom manufactured for any frequency in the range 68-418MHz, and the 2m (144MHz) version is normally made and trimmed as a dual band, 144/433MHz aerial. |
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FLEXI-WHIP prices including carriage:
| Frequency band | Length cm | Price |
| 68-88MHz loaded | 50 | £25 |
| 118-137MHz loaded | 49 | £25 |
| 118-137MHz (Pilot) loaded | 15 | £25 |
| 144/433MHz dual band loaded | 47 | £25 |
| 144-146MHz full length | 49 | £15 |
| 156-162MHz full length | 45 | £15 |
| UHF air band full length | 24 | £15 |
| 430-440MHz full length | 17 | £15 |
Connector types, BNC plug, angle BNC, SMA plug, SMA socket, TNC plug, PL259, angle PL259, F plug, 6mm stud, 1/4" stud.
Note: 6mm stud suits Pye/Phillips PF45 and PFX. 1/4" stud suits MAXON, MOTOROLA & KENWOOD.
Flexi-whip for Wouxon KG699E 4m Handheld, 51 cm long and supplied with SMA socket, £25.
Flexiwhip for ICOM E90 4m handheld, 51 cm long and supplied with SMA plug, £25.
2m/70cm dual band Flexi-whip for Wouxon, 47cm long with SMA socket, £25.
MOBILE WHIP AERIALS
QUARTER WAVE WHIPS Are cut from 2.54mm diameter 17/7PH stainless steel to suit any centre frequency in the range 68 to 450MHz. They are supplied with a hinge adapter, or a 3/8" UNF stud, or even with a PL259 and all include a protective plastic tip. 1/4 wave whips in the range 70-90MHz are priced at £12 each including carriage. 1/4 wave whips 90-450MHz are £7.50 including carriage.
| 2m/70cm DUAL BAND MOBILE WHIP This is a centre loaded whip with antiphase coil so the full 46cm length corresponds to 1/4 wave on 144MHz giving 0dBd (2.15dBi) gain. The antiphase coil allows the top section to be in-phase with the bottom section on 70cm to provide 3dBd (5.15dBi) gain. Robust and reliable ferrules connect the 17/7PH whips to the antiphase coil and the assembly is solid moulded in nylon and likely to outlast the choice of end lugs. The aerial is supplied with a hinge adapter, or a 3/8" UNF stud, or even with a PL259 and includes a protective plastic tip. Price £23.00 including carriage. |
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