(Näkyi olevan Vipusessa 12/2008 linkki tänne. Täytyy sivua jossain vaiheessa päivitellä. Ja uusia muuntajia ja konfiguraatioita on tarkoitus testailla. Mm. niitä jutussa mainittuja kiikarirunkoja.)
Two-wire beverage's other wire is hanging due to weight of snow on it. November 2009, two weeks before CQWW CW contest.
These receiving antennas are inspired by "ARRL Techniques and Antennas for Low Band DXing" and "ON4UN's Low-Band DXing (3rd and 4th ed.)" books by John Devoldere, ON4UN. Some articles have been in Internet too.
I'm did major update to my Beverage antennas during summer and autumn 2005. Most of the wooden supports have rottened after many years and worst of them were replaced with pressure treated timber. All transformers were redesigned and one common mode choke was installed to the feedline. The termination grounds were improved also.
New reflection transformer being smoked.
Two reversible Two-Wire Beverages with 70/250 degrees (165 m long) and 135/315 degrees (185 m long) directions. One 150 m long traditional Beverage is set up for South, 190 degrees. Short Beverage 120 meters long is running about north 30 degrees. This has been valuable in hearing KH6s and KL7s. Plan to install other similar and feed them staggered phased array. Almost all Beverages are outside of the 160 m vertical's radial system. Short one is running very close to vertical antenna. Added a relay to vertical to float it in receive and it eliminates noise generated by transmitting antenna. I will add K9AY loop system later, when we finish our club project: OH4AB K9AY projekti (in finnish only). We test this antenna on Kustavi IOTA pedition. Need to find time to set it up in home station. I played with Yaesu VX8 handheld with GPS and got locations of beverage ends and calculated their directions and lenghts.
Recently rebuilt Two-Wire Beverage for 70/250 degrees is made from 1,4 mm thick hot-dip galvanized steel wire. This inexpensive wire is made for electricity fences used in farms. One roll had 400 meters and it cost about 20 euros.
Other Beverages use 0,85 mm copper clad steel. This wire is taken apart from old two-pair telephone cable. This is free, but it is quite big task to separate individual wires from each other.
Two-Wire Beverages have supports made from wood. New ones are pressure treated timber, old ones are taken from the forest. Horizontal support is about 35 cm long piece of pressure-treated timber. Wires are going through electric fence insulators fixed with 3 inch nails to these supports. Longer normal Beverage is just hanging on the tree branches. Short has three posts made from 2x2 pressure treated timber.
All rebuilt Beverages are installed quite high. Atleast 2,5 m high and new posts are 3 m high. Wire has been lifted above tree branches where special supports are not used. There was often broken antennas due to wildlife when wires were around 2 meters high. I hope they are now high enough.
Traditional Beverage has vertical terminations at both ends. Two-Wire Beverages have sloping wires in near end and far ends are running vertically. Traditional Beverages have terminations made from 1 watt 470 ohms carbon composite resistor, it is connected to about 1,5 meter long copper stake (short one has only 1 m aluminium profile) in the ground. I have not checked what value termination should be. It works quite well already. Termination grounds are made from galvanised steel and copper pipes. Traditional Beverages have only one ground rod in far-end. Two-Wire Beverages need better grounds in both ends. There is now mix from three to five ground rods in different ends. Traditional Beverages' feed ends are sharing same ground rods with 120/300 degrees Beverage. Coaxial cables are not grounded to same ground as transformers. Unused antenna's transformers low impedance outputs are connected straight to ground or via 50 ohm resistor (two-wires).
Traditional Beverage has binocular core BN 202-73. Amidon FT-50/75 ferrite cores are used in one two-wire beverage transformers. T4 transformers have 8:32 turns. Other T1 (normal 1:9) is with separate windings 8:21. Reflection transformers, 22:33 turns, is used in Two-Wire Beverages and improvement in F/B is noticeable compared to antenna without this transformer. All transformes have galvanically separated primary and secondary windings. Two-Wire Beverages' transformers are not too well tested, so there will come some changes later. There should be different transformers because there is different wires used. Binocular cores recommended by W8JI and several others seems to be better choice. Changed binocular cores to 70-250 two-wire beverage in october 2009. First tests are done and it seem to work OK. SWR is smoother than before, as it should be. These new transformers are also making antenna more quiet than before.
About 20 meters of RG213 with PL259 connectors is used from hamshack to first relay box. This relay box connects to one Two-Wire Beverage box with RG58 jumper cable with BNC-connectors. Nearest relay box is connected to remote Beverage hub with 1/2" Heliax cable. This cable uses N-connectors and is about 100 m long. This is made from few shorter lenghts. There is also common-mode choke (about 20 turns of miniature coaxial wound on FT-114/J toroidal core) and cable sheath is grounded in one ground rod about 5 meters from Beverage antenna grounds. Coaxial cables are not grounded in any Beverage boxes. Remote hub is starting point for one Two-Wire Beverage and two traditional Beverages. All Beverage boxes connect to relay boxes with RG58 jumpers.
Different antennas can be selected from hamshack with one easily turned rotary switch. If this switch is tight to turn, it will be very painful during long contests. Actually my left elbow has been quite sore since 2010 winter and I think this switch is main cause. I have to design some push button operated switching. There is also a display that shows selected direction. Several relay boxes are used to connect each Beverage. All relays, which have four sets of points, are working with 12 VDC. Separate control cable is running to each box from hamshack. Starting with 10-pair telephone line and continuing with 2-pair telephone line. Without any DC power there is 70 degrees Beverage always in-line. Both center conductor and coaxial sheath are switched on all relays.
Two Wire Beverage box. Push-pull transformer T4 is on the right and 1:9 transformer T1 is on the left side. Relay is in the middle. M6 stainless bolts and nuts are used for attaching Beverage wires on the top and for ground connection on the bottom. Unused transformer output is connected to ground via 50 ohm (2 pcs 100 ohm parallel) carbon composition resistor.
Reflection transformer installed in cast-aluminium box. Stainless steel bolts above are insulated from box with plastic washers. This is new one with BN 73-202 core.
Feedpoint of 70/250 Two-Wire Beverage. Transformers and relay are inside grey PVC box . Left you can see new relay box #1. Both center conductor and shield of coax are switched. Unused cable was connected to ground via 50 ohm resistor. This needed to change when relay was damaged and new one was replaced. Need to make some changes later. There was poor connection with cable and connector. That was resoldered for better reception.
Remote hub in the woods. Right one (white-yellow wires) is Two-Wire Beverage for 135/315 degrees and red wire vertically on the left is 150 m Beverage for 190 degrees. Beverage relay box, one two-wire box and two 1:9 transformers are located here. 70/250 Two-Wire Beverage runs above this hub about three meters high. Finally autumn 2009 we replaced rotten wood with pressure treated.
New beverage supports are three meters high..
For CQWW we did some temporary modifications. 70/250 degs antenna was used as is. We pulled one 250 m long wire towards southeast. It was terminated with 470 ohms and 50 m radial. Another around 200 m wire with similar termination to west. 135/315 degs antenna was connected as one wire with 470 ohm termination. Northern short antenna was disconnected. These seem to work quite well.
I put up one conventional Beverage temporarily to catch ET3PMW. I heard him with existing Beverages, but not too well. Could not make a call. So, I took all the wire what I had ready for the last two-wire antenna, 9:1 balun, grounding stake and a 470 ohm terminating resistor made from 10 pcs of 4.7 kohm 1/4 watt resistors in parallel. I just took a compass and pull the wire between the trees and bushes about towards ET. Same night I worked Paul as a new one. The propagation was so much better I could hear him with my vertical antenna, but reception with this new Beverage was very good. It was so much more quiet compared to my two-wire Beverages that it's a pity I can't have them all like this. Anyway I took it away because it was running very low and through couple of neighbours land. But for future it would be practical to put up to hear some DX peditions.
I put up a single K9AY loop before CQ160 '05 towards western EU. Original K9AY dimensions: 7,6 m high and 10 m long, ends 1.5 m up. 1:9 balun on Amidon FT 50-75 core with separate primary and secondary windings. Eight trifilar turns as secondary and eight turns as primary. 365 ohm terminating resistor. About 1 m long copper stake for grounding. I will test with different terminating resistor values and plan to make a relay system for four directions with two loops. First impressions were mixed. It seemed to make wonders with some UR stations nearly disappearing when switching from vertical to loop. Later I could not make any improvement to my vertical. It could be propagation related. I will continue RX testing. The loop is supported with 10 m long fishing pole stuck into snow.
After moving to SW Finland I have been quite QRT. I just made a coaxial shielded loop according to some instruction found in internet. It is made from 75 ohm CATV cable. Yesterday (12th May) we visit flea market in OH1AD and I found small air variable capacitor for this project. We'll see how it works. Atleast I could hear some OH stations ragchewing on 80 m phone. Below two pictures.
Loop is hanging beside balcony glass.
Tuning capacitor for coaxial loop.
I made also loop for 160 meters using same tuning as above. Only need to make a longer loop from same materials. Now I put it up in our apartment in Pieksämäki and use it with my PMSDR.
End post of two wire Beverage towards USA is in very bad condition. Need to be replaced in autumn.
Same goes with this starting point for Beverage above and southern Beverage.OH4KZM resting behind.
One support for JA-EU/SA two wire beverage in snow.
New relays for selecting which antennas to choose from.
Updated: 24-01-12
© 2000-2012 Jukka Tarvainen