Home Built Buddistick Antenna

Home Built Buddistick Antenna

W3FF made the original instructions on building a home built Buddistick. He commerically manufactures the Buddipole and Buddistick. This is the Buddistick that I made. It was built similar to the instructions but I changed a few things. I didn't use the speaker wire, I used # 14 enamel wire for the coils and inside the bottom tube. The top piece I made from 1/2" PVC and drove a 3/8" X 24 coupling into the 1/2" PVC (it makes a tight fit). If you use the alternate whips I would do it differently (see below). Down Load the complete instructions below.

I made the bottom pole first. It is made from 3/4" PVC sch. 40, 26" long. I drilled a small hole 1" from the top and bottom (only through one side of the pipe). I then put in a # 14 enamel wire inside the pipe and put the wire out through the holes. The bottom wire only needs to be 1" but the top will need to extend out about 6". On the bottom I drill two holes (at right angles to one another) for 6 / 32 bolts (one of the holes need to be close to the wire). Insert the bolts and nuts. Scrape off the enamel off the bottom wire and secure it to the bolt closest to it (I soldered a lug on mine). Place a second nut to hold the wire onto the bolt and then place the Wing nut on the bolt. On the other bolt place a Wing Nut on the bolt (this will be used for the coax shield and Radial).

Cut the coil forms according to the chart below (use 3/4" PVC). Drill a hole all the way through the PVC (this should be a tight fit for the # 14 enamel wire) 1" from each end, the holes should be oriented the same way. Push one end of the wire all the way through the pipe leaving about 6" exposed. Wind the number of turns indicated in the chart below and then push the end all the way through the pipe to secure the coil.

Whip Mounting Detail 9 1/2' Whip w/3/8 X 24 Thread

Alternate Whip Mounting Detail 72" Whip w/1/4 X 20 Thread

Homebuilt Buddistick - pdf

Mounting the antenna, I put a 3/4" plug into a coupling (slip on one end for the plug and threaded on the other end for the antenna) and mounted the assembly on a spring clip. I can then place the spring clip on a table etc. It works good up to ~ 1" table, if thicker it will then lean to one side. I'm working on a different mount.

Attach the Radial and Coax, the Radial is an elevated Radial, it doesn't touch the ground.

Using the above chart as a starting point, hook-up your antenna analyzer and find the lowerest SWR. If the frequency is high then you will need to lenghtened the radial, etc.

If you don't have an antenna analyzer then you will have to use your SWR meter on your radio or tuner. To get the approximate setting for your tuner tune for maximum noise and then check the SWR.

Whip Mouting Detail 3/8" X 24

Buddistick Components Whip - Coils - Bottom Pole - Clamp

Buddistick Antenna Top Section

Buddistick Antenna / Bottom Section 10M, 12M, 15M, 17M Configuration

Buddistick Antenna / 40M Coil / Bottom Section

Operating & Tuning - Home Made Buddistick

 

I did an analysis of the Buddistick that I made. The radial lengths are different than what was published in the article as I built mine a little different. I corrected the table above. I used EZNEC to model each configuration. Below are the results, showing the SWR curve for each band. It is based it on a height of 4' (off the ground) for the Buddistick and 1' at the end of the radial. The radial has to be above ground. 

10 M SWR Curve 

12 M SWR Curve 

15 M SWR Curve 

17 M SWR Curve 

20 M SWR Curve 

30 M SWR Curve 

40 M SWR Curve 

60 M SWR Curve

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10M Vertical Antenna

10M Vertical Antenna

After reading an article by N2UHC on a 10M vertical dipole I decided to build my own. The antenna in the article was made from electrical conduit. I had some problems with the electrical conduit as it was very hard to tune. I have built several of the Copper Cactus 2M antennas and have also been building EH antennas, so I decided to use similar building methods and material for my 10M vertical dipole (copper pipe and PVC pipe). I used 3/4" copper pipe for it's rigidity and the 1/2" copper pipe allows for adjustment. I began by modeling the antenna using EZNEC. I decided to mount the antenna close to the ground. This gives the antenna a low angle of radiation. You can notice that you have a decrease in the gain but I think the low angle of radiation will make up for the loss in gain.

Materials

3/4" X 10' Copper Pipe Lowe's / Home Depot

1/2" X 10' Copper Pipe Lowe's / Home Depot

1 1/2" PVC Sch. 40 Pipe Lowe's / Home Depot

3/4" X 1/2" Copper Pipe Reducers Lowe's / Home Depot

# 8 or #10 X 1/2" Sheet Metal Screw Lowe's / Home Depot

SS Hose Clamps Lowe's / Home Depot

With the price of copper, you might want to use alumunim tubing.

Start by cutting the 3/4" copper pipe in two 5' sections. On one of the section mark 1', 2', and 3'. At the marks drill a 3/8" hole through the tubing on one side. All the hole should be lined up. On the other section mark at 6" and 1' and drill 3/8" holes through the tubing on one side. These holes will be used for mounting the copper pipe to the PVC pipe.

The 2 reducers have to be modified. Using a hack saw cut a groove in the 1/2" end down to the 3/4" section. This will give the hose clamp room to compress the reducer and hold the 1/2" pipe. Now on the inside of each reducer you will find a little tit. This is used to stop the pipe at the correct location when inside of each reducer you will find a little tit. This is used to stop the pipe at the correct location when Solder the reducer onto the 3/4" pipe. On the section that has two holes, solder the reducer on the opposite end.

Cut the 2 - 3' section of the 1/2" copper pipe. This will be used for the ends of the antenna. Slide the 1/2" pipe into the reducers leaving about 2' exposed and secure using the hose clamps. Lay out the PVC pipe and the two sections of the antennas. The spacing between the two sections should be approximately 1". Drill a hole through the other side of the tubing where you have the 3/8" holes. This hole should be sized so the sheet metal screw will rotate freely. Now place the copper pipe and PVC pipe according to the drawing. The PVC should extend approximately 14" above the center of the dipole. Using a 1/8" drill bit drill through the hole in the copper pipe into the PVC. Fasten the copper pipe to the PVC pipe using the sheet metal screws. Now mount the coax to the antenna. The braid of the coax should be on the section closes to the ground. There are many ways to connect the coax to the antenna (using screws, soldering, etc.). Mount the antenna using the PVC pipe. Mounting solutions is up to you. The antenna may be tied down with non-conduction rope. This will give it more stability. After mounting the antenna, connect it to your rig and tune the short pieces (1/2") to obtain the best SWR. As can be seen from the SWR plot the 2:1 bandwidth is over 1 Mhz.

6M Vertical

Make a 6M vertical dipole using the same model except the 3/4" pipe sections are 3' long and the 1/2" pipe section are 3' long with 1 1/2' exposed. Antenna would be ~ 2 1/2' above ground to 11 1/2'. I started with the antenna at 2 feet above ground similar to the 10M antenna but after tuning the 1/2" copper pipe ended up being 1 1/2 feet instead of 2 feet.

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Double T Bar Verticals

Double T Bar Verticals

The 20M Vertical Double T antenna is designed to use available aluminum antenna tubing. This tubing can be shipped UPS in 6 foot sections. The T bars are made from 3/4" tubing and the vertical is made from sections of 1" tubing. The T Bars are 5 foot long. The vertical sections are 6 foot with a center section. The center section is made from 2 - 7 1/2" pieces of tubing with a 1" gap for the transmission line. The middle section are joined together by inserting a piece of 3/4" PVC sch. 40 plastic pipe. There is a little slop between the PVC and the tubing but is pretty snug. Use sheet metal screws to secure the tubing to the pipe.

Double T Bar Vertical antenna are vertical antenna with cross bars on the top and bottom. These crossbars provide capacitance loading thus reducing the size of the antenna. There are several companies that make them commercially. Force 12 and Transworld have reduced sized multi-band H vertical. Force 12 also make full half wave single band Double T Bar verticals. These commercial antenna are very portable and have been used on DX Expeditions.

This antenna is designed to be 2 feet off the ground. You can use a piece of 3/4" PVC Pipe to mount the antenna to a pipe inserted in the ground. Leave at least a 2" gap between the antenna and pipe (this is high resistance / high voltage point). The transmission line needs to lead away at a 45 degree angle. This will prevent the transmission line from interferring with the antenna.

20M Double Bar T - SWR Curves


20M Double Bar T - Elevation Plot

20M Double Bar T - 3D Plot

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