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ANTENNAS ( AERIALS ) 1 THE ANTENNAS AT MØMTJ Before having to dismantle my shack and antennas to to a house move, I used five main types of antennas - this has now changed somewhat, see further down page. Also see: Antennas 2 which includes ideas Top Band antennas for 160 metres Antennas 3 where Felix Scerri VK4FUQ discusses Loop Antennas, baluns, masts & other related topics Antennas 4 provides many antenna ideas particularly for multi-band operation & also gives information about antenna trimming, knots for wire antennas and useful antenna rigging accessory ideas. Antennas 5 VHF and UHF antenna for 144 MHz and 430 MHz 2010 : Antennas used up until 2010: 1) A trapped Inverted L for 80m and 40m fed by RG213 coaxial cable to the LDG Z-11 Pro antenna matching unit in the shack. This can be used on all bands from 80 through to 10 metres. The support post is installed at the bottom of the garden with the end of the antenna wire being supported by Dacron rope that is attached to a pulley on a pole at the apex of the roof. This excellent antenna is still use. more 2) A trapped dipole for 20m and 10m. This was fed by 75 ohm twin feeder to a 1:1 balun then on to the AMU via RG213 coaxial cable. It was initially installed horizontally, but more latterly installed with one leg supported vertically on a 7 metre fibreglass 'Sota' pole with the other leg supported horizontally about 2 metres above the ground. A rather unorthodox arrangement for a balanced dipole, but it seemed to work ok, it looked much neater than a horizontally slung dipole and also offered a more omnidirectional radiation pattern. more 4) A compact Inverted L for the 160 metre band - Top Band - shortened with a loading coil. more 5) As N9TAX Dual Band Slim Jim (J-Pole) antenna for 2m and 70cms. This was fixed near the top of a 10m telescopic fibreglass fishing pole that I pushed up whenever it was required. more 2011 - 2012 : Current Set Up - as at October 2012: 1) A trapped Inverted L for 80m and 40m fed by RG213 coaxial cable to the LDG Z-11 Pro antenna matching unit in the shack. This can be used on all bands from 160 through to 10 metres. The support post is installed at the bottom of the garden with the end of the antenna wire being supported by Dacron rope that is attached to a pulley on a pole at the apex of the roof. A simple single sloping wire element provides use on the 17 metre band while Top Band is achieved with the addition of a switchable base loading coil. A good antenna. more 2) Delta Loop Antenna - 16 metre loop of wire in triangular Delta shape, hung from the top of the pole supporting the inverted L antenna and fed via RG213 coaxial cable via a 4:1 balun. The loop is really a single band antenna cut for one wavelength on the band of interest, however it also can be pressed into service for some higher bands - a good, cheap and easy to install aerial; Often works better than the inverted L on the higher bands, but on 10 metres the tuned 10 metre dipole in the loft is sometimes better. more 3) Dual Band Fan Dipole, made from thick loudspeaker wire, mounted horizontally in the loft space for 10 meters an 6 metres. Cheap & effective. 4 & 5) G Whip End Fed Zepps (EFZ's) for either 20m, 15m or 17m or the G-Whip "WideBander" which is an 'UnTenna' style antenna that can be used for 20m through to 10m using good quality G Whip 9:1 UnUn; useful additions for antenna flexibility. more 6) A half wave wire J-pole fixed to a telescopic fibreglass fishing pole for 10m. Cheap and effective. more about J-Poles 7) Watson W-50 vertical dual band collinear antenna for 2 metres and 70cm mounted on a lightweight aluminium push-up telescopic mast to a height of approximately 7 metres a.g.l. more 8) A DK7ZB design dual band Yagi antenna, with 5 elements for 2 metres and 8 elements for 70cms, mounted horizontally for SSB. A lightweight antenna rotator is employed and uses the same push-up telescopic mast that the W-50 is mounted on. Hight above ground level is again approximately 7 metres. The DK7ZB is an excellent twin band Yagi antenna. more 9) N9TAX Dual Band Slim Jim (J-Pole) antenna mounted in the loft as a back-up antenna for 2m and 70cms. Very good. more Knots: Knots for securing wire aerials and other things more here H.F. ANTENNAS  A typical Delta Loop antenna - diagram by W5SDC - gives multi-band operation with minimal cost. My Delta Loop is fed near the bottom corner - it cannot be fed at the top, as in the diagram above, due to unwanted interaction with the antenna wire of the Inverted L antenna which is supported on the same pole. more Inverted L Antenna for 80m and 40m (and some other HF Bands from 80m to 10m)  The basic layout of the Inverted L Antenna (Practical Wireless) The first antenna that I installed was for
HF. I decided on an Inverted
L that incorporates a 7MHz trap so that it can be used on both 7MHz (40
metres) and 3.5 MHz (80 metres).
The design of this Inverted L is well known and a good design has been published previously in Practical Wireless by Len Paget GM0ONX. It is based on one half of the famous W3DZZ trapped dipole antenna. It can be made entirely from scratch as a DIY project, or the 7MHz trap could be purchased commercially as a ready made item, or whole antenna can bought as a complete kit from Tony Nailer, G4CFY, at Spectrum Communications. I opted to buy the 7MHz trap from Spectrum Communications, as I already had most of the other materials required - rope, egg insulator, plastic box, and some good aerial wire. The Spectrum Communications trap is solid and well made and 'potted' to protect against the elements. This antenna is tuned for 40 metres and 80 metres, but the VSWR is acceptable on several other bands being in the region of 2:1 to 5:1. The designer anticipated that this antenna would be usable on five of the H.F. bands between 80m and 10m. I have found that with the use of the Antenna Tuning Unit it can be used on all of the H.F. bands. However the polar radiation pattern may very well be less predictable on bands other than the intended 40 and 80 metres, and it may well be less effective than might be desirable - but it does work! The antenna is in the back garden, while the shack (radio room) is in a bedroom at the front of the house. It is fed by a 30 metre length of RG213 coaxial cable (it is not possible to use twin feeder for this type of antenna as the Inverted L is an UN-Balanced aerial, whereas twin feeder is balanced). With this length of cable I estimate the loss in the feeder alone to be about 1dB at 7MHz. The feed point of the aerial is located at the base of a 16 foot high wooden pole near the bottom of the garden. The horizontal top wire returns to a fibreglass pole installed at the apex of the roof. + 17 + 160: I have since added a separate sloping wire element for the 17 Metre Band and a switchable loading coil for Top Band - see notes below...  Photograph
showing
the wooden support post and termination point of the Inverted L antenna
The post is coloured green with green fence treatment to mast it somewhat. I have also placed it near the bush to provide further camouflage.  The low loss RG213 coaxial cable runs from the shack at the front of the house up into the loft and exits into the back garden down the rear wall, through some garden hose to offer some protection along the flower bed to the bottom of the garden where it is connected to the base of the Inverted L antenna.
 The Inverted L antenna - lower section now nicely camouflaged. The wooden support post is some 6 metres long.  The photograph above shows the Dacron ropes
supporting the ends of the Inverted L and Dipole antennas are held in
place at the top of the fibreglass support mast by a pulley - one
pulley for each
support rope. This facilitates rapid lowering of either antenna for
adjustment or replacement. This
photograph also shows a second
rope and pulley system that was originally used to support the 20m
dipole and is now used for the top band inverted L wire aerial.
I needed a good reliable knot for securing ropes when installing wire antennas and have found the Bowline to be one of the most useful, it is strong and easy to tie. A Bowline will not slip in any circumstances and, usefully, the more load that is put on it, the tighter it gets.  The Bowline Knot A Bowline can be used to tie two ropes together and should be used to tie a support rope to a pulley, dipole centre and other antenna items. It's
important
to use the correct knot for the job when fixing up wire
antennas. I find the Bowline is a very
useful for fixing end, egg and dog-bone insulators to the ends of the
wire and/or ropes. The Round Turn & Two Hitches, Anchor Bend
(Anchor Hitch) and
Buntline Hitch knots are very good for tying a rope to a pole or a
mast. A Double Sheet Bend can join two pieces of rope together - even
if they are of unequal size. 'Animated Knots' will show you how to do
them: http://www.animatedknots.com
 Photo showing pulley fixed to the top of the wooden support post and the aerial support rope that it holds in place.  The
Spectrum
Communications Trap
View
of trap showing
that the joints have been thoroughly sealed against the weather with self amalgamating tape and silicone sealant.  Just for good measure I sealed the internal side of the machine screw that forms the connection terminal against the weather with Watson sealant putty. Adding Top Band to the 80 / 40 metre Inverted L Antenna:
Due to an aborted house move in 2010 I had removed all the antennas. While re-establishing the aerials in 2011, and considering space limitations, I decided to experiment with adding a loading coil to the 40m / 80m Inverted L aerial. The loading coil has a link wire to short it out of circuit when using the aerial for 80 metres and 40 metres. The link wire is removed when Top Band is required. I also took the opportunity to replace the original wooden post with a strong 6 metre tall fibreglass pole. The coil consists of approximately 37 turns of PVC covered antenna wire wound on a short piece of PVC pipe. Once the required points of resonance were set for 40 metres and 80 metres, the link wire was removed and number of turns on the coil were adjusted until the required point of resonance was found on the 160 metre band. I set it to around 1900 kHz - the bandwidth is quite narrow. Once the work was done, the joints and connections were sealed with either Liquid Electrical Tape or self amalgamating tape, then the connecting box, V bolts and white PVC pipe were sprayed with green paint to help it all blend in with the surroundings a little better. Adding the 17 Metre (18 MHz) Band to the 80 / 40 metre Inverted L Antenna: The Inverted L is not too good for the 'WARC' bands so to obtain better performance on the 17 Metre band I added a single slightly sloping wire element cut for that band. The lower end of the wire is permanently connected to the feed terminal on the junction box, the other end is tied to a small dog bone insulator. This dog bone is then supported by a length of thin para-cord which is tied to the horizontal wire of the main Inverted L element. (N.B. The 17 metre modification is not currently shown in the photographs below.)  Work In Progress! - September 2011 Reconfiguring Inverted L with additional Top Band Loading Coil for 160 metres. A strong 6 metre tall fibreglass pole replaces the original heavy wooden post.  Adding 160 metre loading coil to the 80m / 40m Inverted L Aerial. The loading coil has a link wire to short it out of circuit when using the aerial for 80 metres and 40 metres. The link wire is removed when Top Band is required. The coil consists of approximately 37 turns wound on a piece of PVC pipe.  Adding 160 metre loading coil to the 80m / 40m Inverted L Aerial. The loading coil has a link wire to short it out of circuit when using the aerial for 80 metres and 40 metres. The link wire is removed when Top Band is required. The coil consists of approximately 37 turns wound on a piece of PVC pipe.  Photograph showing the Inverted L antenna with additional vertical wire element and position of Delta Loop  The commercial version of the basic 80m - 10m Inverted L is available from Tony Nailer at Spectrum Communications
Delta Loop Antenna - Tuned for the 17 metre band but also usable as a multi-band operation
A typical Delta Loop antenna - diagram by W5SDC - gives multi-band operation with minimal cost.
My Delta Loop is fed near the bottom at one corner - it cannot be fed at the top, as in the diagram above, due to unwanted interaction with the antenna wire of the Inverted L antenna which is supported on the same pole. It consists of a 16 metre long loop of wire in triangular Delta shape, hung from the top of the pole supporting the inverted L antenna and fed via RG213 coaxial cable via a home-brew 4:1 balun. A loop is really a single band antenna cut for one wavelength on the band of interest, however it can also work on higher bands with an ATU - as a good, cheap and easy to install multi-band H.F. aerial. Performance is a little better than the inverted L on the higher bands, but on 10 metres the tuned 10 / 6 metre wire 'fan' dipole in the loft can still be better.  Apex of Delta Loop by M0MTJ  Bottom left corner of Delta Loop antenna by M0MTJ  Feed point of the Delta Loop at the bottom right hand corner  The Feed Point of the Delta Loop Antenna is at the bottom right hand corner The Antenna is fed via a 'home brew' 4:1 balun by M0MTJ Below are the VSWR measurements
for the 16 metre long loop which has been measured an cut for resonance
in the 17 metre band. For comparison are the measurements for the 12
metre long loop (which has not been optimised) and an 18 metre long loop
which is of arbitrary length:
Arthur M0PLK (SQ2PLK) at Ham Radio Shop supplies an interesting lightweight self supporting Delta Loop antenna: http://ham-radio.urbasket.eu - see the review on the Polonia DX Award here: http://pdxa.one.pl/articles.php?article_id=17 LOOP ANTENNA LINKS: See lots more links to Loop Antennas on my links page here
Compact
Antenna
for
Top
Band
A Shortened Inverted L for 160 Metres
Despite the dreadful noise on top band caused by modern electronic gadgets and the difficulty in accommodating a necessarily large aerial in a small garden, I was keen to try to get on to top band. I experimented with some different ideas during 2009, some of which are shown on this page. Eventually I settled on the design shown below. It is an Inverted L type aerial, shortened by the use of a loading coil. It uses a fibreglass telescopic fishing pole to allow it to be easily lowered out of sight when not in use. Read more on Antennas page 2 here>  uses a fibreglass telescopic fishing pole to allow it to be easily lowered out of sight when not in use. Read More Here on Antennas page 2 > ANTENNAS FOR VHF and UHF - 2 m & 70 cms Watson W-50 dual band for 2m & 70cm For 2m and 70cm FM I use a Watson W-50 "white stick" vertical dual band collinear antenna mounted on a lightweight aluminium push-up telescopic mast to a height of approximately 7 metres a.g.l. at the base of the antenna. Dual Band Yagi for 2m & 70cm For 2 metres and 70cms SSB there is a horizontal DK7ZB design dual band Yagi antenna. This has 5 elements for 2 metres and 8 elements for 70 cms. A lightweight antenna rotator is employed and uses the same push-up telescopic mast that the W-50 is mounted on. Height above ground level is again approximately 7 metres. The DK7ZB is an excellent twin band Yagi antennaWatson W-50 vertical dual band collinear for 2 metres and 70 cms FM.  My DK7ZB 5 + 8 element dual band yagi for 2m and 70 cm - designed by Martin Steyer DK7ZB Available from Arthur M0PLK (SQ2PLK) at Ham Radio Shop: http://ham-radio.urbasket.eu Also available from VPA SYSTEMS by SQ9VPA http://www.vpa-systems.pl Kits available from NUXCOM.de : http://shop.nuxcom.de 2 Meter J-Pole Antenna for the garden shed - and other J-Pole antennas for 6 metres and 10 metres :
While experimenting with antennas in the garden in the summer of 2012 I thought that it would be good to have a hand-held radio in the shed to do some monitoring and make a few contacts. To improve upon the performance of the 'rubber duck' antenna I quickly made a J-Pole antenna for the 2 metre band. It is made from a 47cm length of 450 ohm Wireman ladder line as the 1/4 wave matching section, plus a 97cm length of stranded wire as the 1/2 wave radiator. It is fed with 3 metres of Mil spec RG58 c/u coaxial cable that is soldered to the 1/4 wave matching section's impedance matching point at 3.5 cm from the bottom. The coax feeder is wound around some PVC tube to form a choke. The completed antenna is taped to a 2.2 metre long fibreglass fishing pole that I purchased from Poundland (for £1.00). It took about 20 minutes to make followed by some testing and adjustment with the antenna analyser. The fishing pole is lashed to the shed with some cable ties. This simple antenna works pretty well, but being so low down signal strengths are not huge, but it's pleasing to get on the air with something so simple and cheap! Now, if it was at the top of my 10 metre long fishing pole. . . . . (!) 
The Shed Antenna - a 2m J-Pole by M0MTJ
Note the simple choke balun at its base made by winding 8 turns of the coaxial cable around a small off cut of white PVC water pipe.  The feed point of a J-Pole antenna made from Wireman 450 ohm ladder line. For the 145 MHz antenna this feed point is 3.5 cm from the bottom of the ladder line section which is on the right hand side in this photograph. The coaxial cable used in this case was Mil spec RG58 c/u. But any good quality, low loss 50 ohm coaxial cable could be used. The wire radiator section is connected to the same conductor of the ladder line as the coaxial cable's centre conductor. For my antenna, fixed to a fibreglass fishing pole, the radiator wire was 97cm in length.  Photograph showing the point where the PVC covered wire that forms the half wave radiator section is soldered onto the top of the 450 ohm ladder line that forms the quarter wave matching section.
D.I.Y. J-Pole Antennas - A really simple, quick and very cheap 'home brew' project
These J-Pole Antennas were inspired by DK7ZB - http://www.qsl.net/dk7zb/J_Pole/wiremanjpole.htmInspired by DK7ZB. The J-Pole is a very effective antenna and being made of wire it is very light weight making it quite easy to fix in different positions. If you have problems installing a permanent antenna then making a wire antenna that can be easily supported on a lightweight push up telescopic fishing pole can make an ideal alternative. The formulas to make a J-Pole antenna from 450 Ohm Wireman ladder line in this way are: Length of 1/4 wave impedance matching section (450 ohm ladder line) Wavelength x 0.223 Length of 1/2 wave radiator (any reasonably strong PVC covered stranded wire) Wavelength x 0.471 The point at which the coax is connected to the 450 ohm ladder line will be about 5 to 10% of the length of the ladder line section up from the bottom. The wavelength at mid point of the 2 metre band (145.00 MHz) is found by the quick calculation 300 ÷ 145 = 2.068 metres So, to make a practical antenna: The 1/4 wave section of 450 ladder line will be 2.07 x 0.223 = 0.47 metres long The 1/2 wave wire radiator will be worked out as 2.07 x .471 = 0.975 metres long The connecting point of the coax will be about 3.5 cm from the bottom of the 1/4 wave section. The optimal point may have to be found by some experimentation - as will the best length for the wire radiator. The length of the wire radiator will be affected by surroundings. For example I fixed the wire to a fishing pole. The proximity of the fishing pole has the effect of electrically lengthening the wire; so using a 97.5cm length of wire fixed to a pole I found that it resonated (as expected) at a lower frequency, it therefore had to be shortened until the point of resonance (indicated by lowest SWR) was around 145.00 MHz. This should be done in the antenna's expected final position since the J-Pole is quite sensitive to its surroundings, so if these checks are done near the ground, once it is raised into its final position the SWR will have changed and the adjustments will have to be done again. I found that 3.5 cm was good for the 2 metre band antenna, but for the 10 metre band version of the antenna a little more experimentation was required: The VSWR reading may not be especially low, even though the point of resonance for the wire radiator may have been found. For the 10 metre band antenna at this this stage was about 1.7 indicating that the connection point of the coaxial cable to the 450 ladder line needs to be adjusted. The ladder line is used as an impedance transformer, transforming the very high impedance (hundreds of ohms) of the half wave wire radiator down to the 50 ohms required by the transceiver and the coaxial feeder cable. This connection point therefore affects the impedance of the antenna, the higher up the matching section it is the higher the impedance will be, and visa versa. Once the length of the wire radiator has been set, the connection point can be moved up and down the ladder line until lowest SWR is achieved. A few centimetres of the PVC insulation has to be carefully scraped away from the copper conductor on each side of the ladder line using a craft knife. The inner conductor of the coaxial cable is quickly tack soldered on the side that is connected to the 1/2 wave wire radiator. The coaxial cable's braid is quickly tack soldered to the opposite side of the ladder line at this point, ensuring that both points are equal distance from the bottom. At this point temporary croc clips could be used, but I preferred a quick solder joint. With radiator trimmed for resonance, the connection point of the coaxial cable can then be moved up or down the ladder line little by little; un-soldering and re-soldering the coax to the ladder line until a lowest possible SWR is achieved, indicating that the antenna is near the ideal 50 ohm impedance. Once the ideal point is found the coaxial cable can be properly and permanently soldered to the ladder line.  6 Metre Band J Pole on the antenna analyser - it's getting close! 10 Meter J-Pole. For the 10 metre band J-Pole antenna this took perhaps another 20 or 30 minutes until I was satisfied with the adjustments. It may take a little longer if using an SWR meter. 6 Meter J-Pole. For the 6 metre band antenna the radiator wire had to be trimmed a little and the feed point adjusted to 6 cm, taking about 10 additional minutes to complete. 4 Metre J-Pole. For the 4 metre band, centred on 70.37 MHz 2 Meter J-Pole. For the 2 metre band antenna the wire radiator took a couple of attempts to get it to the correct length when attached to a fishing pole, but the feed point was spot on first time at 3.0 cm, again taking about 10 additional minutes to complete. Here are some suggested dimensions for the 2 metre, 6 metre and 10 metre band versions, when supported by a fibreglass fishing pole:
To re-cap, the 1/2 wave section should be adjusted for resonance and the feed point position adjusted for minimum VSWR.
Sealing and waterproofing.
Once the antenna is complete and has been checked and tested all the
bare joints should be sealed against the weather with liquid electrical tape and self amalgamating
tape. The coax should also be secured against
the ladder line with a nylon cable tie as a strain relief to prevent the
soldered feed point joints from breaking.
End
Fed
Zepp Antennas for 20m / 17m and 15m :
 The end fed Zepp is extremely versatile - it can simply be hung from the fascia board or guttering just outside one's window: The 1/2 wave wire radiator made of high strength Kevlar is easily sloped down the garden and is a camouflage green in colour so as to be almost invisible. The G-Whip Zepp is supplied with a fascia board insulator, a throwing line with plus cable strain relief and fittings, the IP65 waterproof resin potted box fitted with UHF connectors (SO239) for coax feeder. The Zepp can be mounted vertically (e.g. using a telescopic fibreglass pole), horizontally or sloping and can be ready in a matter of minutes. I then decided to try an excellent new design developed by Geoff G4ICD - an End Fed Zepp antenna with a difference. The G-Whip End Fed Zepps are high efficiency, resonant mono band antennas utilising a half wave radiator, however this new G-Whip design by G4ICD dispenses with the long trailing 1/4 wave twin feeder matching section and counterpoise and, instead, uses a helical tuned unit. Using versions for 20m, 17m and 15m will enable me to get on the air with the minimum of fuss since the G-Whip end fed Zepp can simply be hung from the facia board or guttering just outside one's window. The high-strength Kevlar, camouflage green 1/2 wave wire radiator is easily sloped down the garden to be almost invisible. G-Whip Widebander : 
GWhip Widebander antenna.
Using the popular idea of feeding a large but non resonant antenna with an impedance converting 9:1 unun. The G Whip wideband antenna consists of a 9:1 unun of GWhip's customary high quality for best efficiency, two 20metre lengths of kevlar wire for the radiator and counterpoise which provide operation from 3.6MHz to 50MHz. Feed with good quality low loss coax and use an ATU to match. The 20 metre radiator wire can be used as a sloper, or supported by convenient supports such as poles or trees in a straight line or 'dog legged'. I use a shorter radiator wire run up a telescopic fibreglass pole for operation on 20 metres an above. Dual Band J-Pole : There is a dual band vertical J-Pole antenna in the loft as a back up for the 2m and 70cm bands.  The excellent Dual Band N9TAX Slim Jim antenna that I use in the loft as a reserve antenna.
More information from Joe N9TAX at: www.n9tax.com Previous Antenna installations:
In mid 2011 I experimented with an excellent N9TAX designed dual band Slim-Jim (J-Pole) antenna for 2m and 70cms. This is made from lightweight 450 Ohm ladder line which can be fixed to the top of a 10m tall fibreglass, telescopic, fishing pole. The N9TAX works extremely well indeed. More information from Joe N9TAX at: www.n9tax.com and buy at: www.ebay.co.uk/itm/VHF-UHF-Slim-Jim-J-Pole-Dual-Band-2m-70cm-Antenna-jpole N.B. I tried to home-brew the DJB-1 dual band J-Pole antenna using plans published by the ARRL in QST magazine. I wanted a neat antenna that could be enclosed in a protective tube to minimise weathering effects. However trying to tune this antenna at UHF frequencies proved to be frustratingly difficult to do and after two full days work I could not get the thing resonate accurately at the correct frequency. Sadly, for this reason, I cannot recommend the Dual Band J-Pole as a home-brew project. The N9TAX antenna on the other hand works very well. However it cannot be enclosed in a tube due to the velocity factor effect de-tuning the antenna's resonant frequencies. (Late 2011) Due to difficulties with the stability of a lightweight fishing pole as a support I moved back to using the lightweight aluminium telescopic mast, with stays, to support a Watson W-50 vertical dual band collinear for 2 metres and 70 cms FM. The excellent N9TAX dual band Slim Jim is now installed in the loft. (2008) W-2000 -
Vertical
Collinear mounted on a temporary 10m telescopic pole:
I no longer have the Watson W-2000 but this is how it was used previously: The Watson W-2000 covered VHF (2 metres / 144 MHz) and UHF (70 cms / 430 MHz) and also, rather usefully, 6 metres (50 MHz) too. The W-2000 is 2.5 metres long and enclosed in white fibreglass with three radial elements at the base. Unfortunately I had nowhere practical to install a separate mast for the VHF / UHF antenna, so this was mounted on top of a 30 foot (10 metre) high telescopic aluminium mast in the back garden. The base of the mast was placed in a handy metal sleeved hole that was already present in a small wall in the garden. Very fortunate indeed! The antenna is connected to the radio via the very low loss Westflex 103 coaxial cable. The cable was left in place permanently, running from the shack in the front bedroom, up into the loft and out of a small hole in the back of the house, down a drain pipe into the back garden. From there the aerial can be connected as an when required: When VHF or UHF operation is required I have to connect the coaxial cable to the Watson W-2000, fix it to the top of the telescopic mast, which is very quick using two V bolts and 4 wing nuts, put the mast in the hole and raise it to a good height. I tend to extend it so that the bottom of the antenna is at about 24 feet in the air, the height of the apex of the house, so it is in fairly clear space. A VHF and UHF aerial needs to be as high as possible since at these frequencies communication is essentially local and 'line of sight' - unless heightened propagation conditions, such as Sporadic E or a Temperature Inversion is prevailing at the time. Even at 24 feet the mast is rather wobbly, so it was tied down using three nylon guy ropes.  The
Watson W-2000 on to of the extended telescopic pole - about 8 or 9
metres high.
  Photograph
of
a Watson
W-2000
on Telescopic Mast at the lowest position.
Our good friend in Australia Felix Scerri, VK4FUQ, uses Inverted V antennas but also highly recommends the Quad Loop style antenna for HF work. These are well worth investigating, and you can read more here: Antennas 3 with more antenna ideas on Antennas 2 and Antennas 4 and the Links Page here and here KNOTS FOR SECURING WIRE ANTENNAS I have found the Bowline to be one of the most useful, it is strong and easy to tie. A Bowline will not slip in any circumstances and, usefully, the more load that is put on it, the tighter it gets. Read more about good knots for amateur radio aerials here... Antenna Trimming Chart and useful Antenna Rigging Accessory ideas On Antennas 4 I have included a helpful Antenna Trimming Chart and some useful ideas for Antenna Rigging Accessories More project ideas here> 73 Mike, M0MTJ 2011 / 2012 Links to further reading: Introducing The All Band Doublet: http://www.cebik.com/content/edu/edu6.html N.B. Create a free account at http://www.cebik.com The All Band Doublet - http://www.cebik.com/wire/abd.html The ALL Band HF Doublet on Ham Universe - http://www.hamuniverse.com/hfdoublet.html Multi Band Dipoles Compared - by ARRL on QST and DX Zone: http://www.arrl.org/tis/info/pdf/9611073.pdf http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=7499 PDF Document - The W3DZZ Antenna - http://www.users.icscotland.net/~len.paget/GM0ONX%20trap%20dipole.pdf (**!!! But don't use coaxial cable with a 'choke balun' at the centre of the dipole! Use twin feeder with the Choke Balun at the other end. Less power loss.!!!***) See Practical Dipole Antennas Compared: http://www.qsl.net/ta1dx/amator/practical_dipole_antenna.htm Practical Antenna For 160 Metres - http://www.iw5edi.com/ham-radio/?a-practical-antenna-for-160-metres,32 http://www.ik1mnj.net/id202.htm More: The website of GM0ONX http://www.gm0onx.co.uk/ The Inverted L - PDF document: http://www.users.icscotland.net/~len.paget/5%20band%20Inverted%20L.pdf Adding Top Band To The Inverted L - PDF Document: http://www.users.icscotland.net/~len.paget/Inverted%20L%20adding%20top%20band.pdf The All Band Inverted L - http://www.antennex.com/preview/archive3/ltv.htm Q.T.H. Move in 2010 !%*?"*!?! We decided that we'd like to move house in 2009, we found a new property in early 2010. My amateur radio aerials were duly taken down and the ham shack packed away. However after months of delays we still had not moved by August 2010, but we were still hoping to move. However after months of messing about and stringing us along our buyer pulled out the very day before we were to exchange contracts later in August 2010. This cost us a lot of time and a great deal of wasted money. Thank you Mrs xxxxxx :-( After a wasted year we decided to stay where we were and take the house of the market. Instead we spent the next eight months remodelling and redecorating. No time for playing radio of course and besides everything was still all packed away in boxes! In mid 2011 I was getting frustrated that I had no radio. So I suppose it's time to think about re-establishing the station and to start planning the installation of some antennas. Of course Jules, my XYL, understandably questions my antennas and experiments! Due to time constraints I will probably start again with a somewhat temporary antenna. I was thinking along the lines of an "Untenna" - so I installed a 7.2 ish long wire supported on a vertical fibreglass pole with a horizontal 'counterpoise' connected via a 9:1 balun to the coax back to the shack. Of course it is a fairly low efficiency multi-band (wideband) antenna, but easy to get going quickly. The GWhip Widebander antenna by Geoff Brown G4ICD is possibly the highest quality antenna of this type available, using a very high efficiency, top quality 9:1 UnUn with a 17 meter wire radiator and 10 metre long counterpoise - a very useful, versatile 'all situations' antenna. As time progressed I re-established my full size trapped Inverted L antenna for 80metres and 40 metres and added a switchable loading coil at its base for use on 160 meters, as described above. Then I gradually re-established the 2 metres and 70 cms antennas with the vertical W-50 and horizontal dual band DK7ZB Yagi - as detailed above.  Antennas 2 | Antennas 3 | Antennas 4 | Antennas 5 | Antennas 6 G-Whip Antenna Products Geoff Brown G4ICD offers a multitude of high quality solutions for portable, mobile and permanent base installations   |
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Mike Smith - MDS975.co.uk © 2003 - 2013
M0MTJ
Amateur Radio; Ham Radio; Radio; Transceivers; HF; VHF; UHF; Data Modes; Morse Code; RTTY; PSK31; SSTV; FSTV; Amtor; Sitor
Antennas; Aerials; Cable; Coaxial Cable; Twin Lead; Masts; Poles; Propagation; Computer; PC; USB Computer Interface; Microphone
Loudspeaker; Filters; Noise Reduction; DSP; Digital Signal Processing; Morse Key; SWR ; Inverted L; Inverted V; Dipole; Doublet.