04-15-2006, 02:40 PM
Review of Butternut HF2V by AI4CB
This is an 80 meter + 40 meter vertical about 32 feet tall. It is basically a full quarter wavelength on 40 meters, and a base-loaded short vertical on 80 meters. Purchased new from Ham Radio Outlet in February 2006 for $269.95. Further information and manual download etc available from: Butternet (Bencher) Antenna Page (http://www.bencher.com/ant_select.html)
I had been using wire inverted-Ls for 80 and 40 meters and those worked fine, but locations of the trees used for supports are inconvenient relative to the best ground mount location and as a result the wires hanging all over the yard looked rather sloppy. The HF2V gave me a way to create a neater installation and is not very noticable from the street.
One complaint is the collection of bolts and nuts provided seemed to have been selected at random – as if whoever packed the thing just grabbed a handful of whatever hardware was handy – and the enclosed inventory of bolts, washers, nuts, bore little relation to the parts list in the instructions. It turned out I was missing one of the 1-1/2 inch long bolts and several of the larger size washers. So I had to scrounge my junk box for replacements in order to finish assembly. And I ended up with half a dozen nuts, small washers and short bolts left over. One has to wonder if this wasted hardware and careless packaging is one of the reasons for the relatively high cost of this antenna.
Assembly was very easy. I had read reviews of this antenna elsewhere that complained that it took “hours” to assemble and nothing would fit. Nonsense. It took less than 10 minutes to assemble the tubing (not counting the time spent scrounging to replace the missing bolt) and maybe 15 minutes to attach the coils etc… One assembly “trick” should be mentioned – if the predrilled bolt holes in the telescoping lengths of tubing don’t seem to line up – simply turn one of the lengths of tubing around and try the other end - the holes will probably match perfectly.
The hardest part was installing the ground mounting post. The instructions suggest digging a hole and packing dirt around the base tube, but I felt that would not be very stable in the soil here. An alternative was to set it in concrete but I didn’t want it to be that permanent. What I came up with instead was to set a piece of PVC pipe in concrete, and just slide the base tube of the antenna into the PVC and sealing around the top of the PVC with some roofing cement to hold it in place. This is stable, but easy to take apart. See photo at this address:
AI4CB's HF2V Ground Mount (http://members.cox.net/ai4cb/Images/HF2V_Ground_Mount.JPG)
At this time I have 16 buried radials of between 30 to 40 feet length each. See the photo for the method of attaching the radials. I took a length of #6 bare ground wire and bent it around the base of the antenna in a loop and with a couple extra bends provided a way to holding it to the top of the PVC pipe with a hose clamp. A wire from the loop goes up to the feedline attach point. Radials (#14 solid copper, insulated) are soldered on and the connections coated with 3M ScotchKote varnish. An 8 foot ground rod is driven close to the antenna base and this also is attached to the loop (actually is an extension of one end of the wire that forms the loop) and to several other ground rods elsewhere in the yard. The feedline is about 70 feet of buryable RG-213, buried a few inches deep. All joints and the coax shield are coated with ScotchKote.
When initially installed, with no radials, just the single ground rod, SWR was about 4:1 on 80 meters and 3:1 on 4 meters. SWR improved only slightly as the first few radials were buried and attached. After four radials, however, symmetrically placed around the antenna, the SWR dropped more significantly, to about 2.5:1 on 80 meters and 2:1 on 40 meters. At that point the resonance frequencies also shifted so the loading coils were adjusted. As additional radials were added, SWR continued to drop slightly a bit at a time and eventually to about 2:1 on 80 meters and 1.5:1 on 40 meters. Not much more change in SWR or resonance occurred after the first 8 radials. The matching coil at the base had to be stretched to several times it’s originally length to reduce SWR on 80 meters to less than 2:1. I later cut off about four turns of the coil so that it would not have to be stretched out so much. Final adjustments yielded SWR of about 1.7:1 on 80 meters at a resonant frequency of 3.540 and a 3:1 bandwidth of about 80 kHz. I have used it with an MFJ tuner higher in the band with no problems. And it’s trivial to change the 80m resonant frequency by loosening the loading coil attachment point and stretching or compressing the coil. On 40 meters SWR is less than 2:1 across the whole band, and about 1.1 at resonance.
I did not guy the antenna. The instructions recommend it for above-ground installation but don’t say anything about guying it if ground-mounted. The antenna can move around quite dramatically in the wind, but it has survived several thunderstorms already this spring with wind gusts up to at least 50 mph, and one winter storm in late February that left it covered with at least a quarter inch of ice and snow. I’m comfortable with its survivability so far. If it does break or bend, it should be a simple matter to replace any damaged segment of aluminum tubing.
There are better 80 meter antennas of course but the HF2V is performing exactly how it should, in my opinion. With few exceptions, if I can hear stations, I can work them with 100 Watts or less. I’ve worked the ARRL International DX Contests, both CW and SSB, and the CQ WPX contest, with results consistent with my casual operations. CW contacts to Europe, the Caribbean and South America are routine for me on 80 meter & 40 meter CW now, and I’ve even had some Japan, Alaska, and southern Africa contacts on 40 meters. On the other hand, I was not able to break through the pileups on the 3Y0X dxpedition with this setup on 80 or 40 m (nor did I expect to). In general, I’m pleased with the performance of the HF2V and would not hesitate to recommend it to others – provided they are willing to understand and accept the limitations on 80/75 meters to be expected from a short, based loaded antenna.
Addendum - July 5 2006:
I also have found that I can use this antenna on 15 meters without a tuner.
I added the 30 meter coil kit a couple months ago. The minimum SWR in this case is around 2. You'll need a tuner if you need lower SWR on 30 meters. But one of the first contacts I made after installing the 30 meter coil was Chagos Island. So it definitely works.
This is an 80 meter + 40 meter vertical about 32 feet tall. It is basically a full quarter wavelength on 40 meters, and a base-loaded short vertical on 80 meters. Purchased new from Ham Radio Outlet in February 2006 for $269.95. Further information and manual download etc available from: Butternet (Bencher) Antenna Page (http://www.bencher.com/ant_select.html)
I had been using wire inverted-Ls for 80 and 40 meters and those worked fine, but locations of the trees used for supports are inconvenient relative to the best ground mount location and as a result the wires hanging all over the yard looked rather sloppy. The HF2V gave me a way to create a neater installation and is not very noticable from the street.
One complaint is the collection of bolts and nuts provided seemed to have been selected at random – as if whoever packed the thing just grabbed a handful of whatever hardware was handy – and the enclosed inventory of bolts, washers, nuts, bore little relation to the parts list in the instructions. It turned out I was missing one of the 1-1/2 inch long bolts and several of the larger size washers. So I had to scrounge my junk box for replacements in order to finish assembly. And I ended up with half a dozen nuts, small washers and short bolts left over. One has to wonder if this wasted hardware and careless packaging is one of the reasons for the relatively high cost of this antenna.
Assembly was very easy. I had read reviews of this antenna elsewhere that complained that it took “hours” to assemble and nothing would fit. Nonsense. It took less than 10 minutes to assemble the tubing (not counting the time spent scrounging to replace the missing bolt) and maybe 15 minutes to attach the coils etc… One assembly “trick” should be mentioned – if the predrilled bolt holes in the telescoping lengths of tubing don’t seem to line up – simply turn one of the lengths of tubing around and try the other end - the holes will probably match perfectly.
The hardest part was installing the ground mounting post. The instructions suggest digging a hole and packing dirt around the base tube, but I felt that would not be very stable in the soil here. An alternative was to set it in concrete but I didn’t want it to be that permanent. What I came up with instead was to set a piece of PVC pipe in concrete, and just slide the base tube of the antenna into the PVC and sealing around the top of the PVC with some roofing cement to hold it in place. This is stable, but easy to take apart. See photo at this address:
AI4CB's HF2V Ground Mount (http://members.cox.net/ai4cb/Images/HF2V_Ground_Mount.JPG)
At this time I have 16 buried radials of between 30 to 40 feet length each. See the photo for the method of attaching the radials. I took a length of #6 bare ground wire and bent it around the base of the antenna in a loop and with a couple extra bends provided a way to holding it to the top of the PVC pipe with a hose clamp. A wire from the loop goes up to the feedline attach point. Radials (#14 solid copper, insulated) are soldered on and the connections coated with 3M ScotchKote varnish. An 8 foot ground rod is driven close to the antenna base and this also is attached to the loop (actually is an extension of one end of the wire that forms the loop) and to several other ground rods elsewhere in the yard. The feedline is about 70 feet of buryable RG-213, buried a few inches deep. All joints and the coax shield are coated with ScotchKote.
When initially installed, with no radials, just the single ground rod, SWR was about 4:1 on 80 meters and 3:1 on 4 meters. SWR improved only slightly as the first few radials were buried and attached. After four radials, however, symmetrically placed around the antenna, the SWR dropped more significantly, to about 2.5:1 on 80 meters and 2:1 on 40 meters. At that point the resonance frequencies also shifted so the loading coils were adjusted. As additional radials were added, SWR continued to drop slightly a bit at a time and eventually to about 2:1 on 80 meters and 1.5:1 on 40 meters. Not much more change in SWR or resonance occurred after the first 8 radials. The matching coil at the base had to be stretched to several times it’s originally length to reduce SWR on 80 meters to less than 2:1. I later cut off about four turns of the coil so that it would not have to be stretched out so much. Final adjustments yielded SWR of about 1.7:1 on 80 meters at a resonant frequency of 3.540 and a 3:1 bandwidth of about 80 kHz. I have used it with an MFJ tuner higher in the band with no problems. And it’s trivial to change the 80m resonant frequency by loosening the loading coil attachment point and stretching or compressing the coil. On 40 meters SWR is less than 2:1 across the whole band, and about 1.1 at resonance.
I did not guy the antenna. The instructions recommend it for above-ground installation but don’t say anything about guying it if ground-mounted. The antenna can move around quite dramatically in the wind, but it has survived several thunderstorms already this spring with wind gusts up to at least 50 mph, and one winter storm in late February that left it covered with at least a quarter inch of ice and snow. I’m comfortable with its survivability so far. If it does break or bend, it should be a simple matter to replace any damaged segment of aluminum tubing.
There are better 80 meter antennas of course but the HF2V is performing exactly how it should, in my opinion. With few exceptions, if I can hear stations, I can work them with 100 Watts or less. I’ve worked the ARRL International DX Contests, both CW and SSB, and the CQ WPX contest, with results consistent with my casual operations. CW contacts to Europe, the Caribbean and South America are routine for me on 80 meter & 40 meter CW now, and I’ve even had some Japan, Alaska, and southern Africa contacts on 40 meters. On the other hand, I was not able to break through the pileups on the 3Y0X dxpedition with this setup on 80 or 40 m (nor did I expect to). In general, I’m pleased with the performance of the HF2V and would not hesitate to recommend it to others – provided they are willing to understand and accept the limitations on 80/75 meters to be expected from a short, based loaded antenna.
Addendum - July 5 2006:
I also have found that I can use this antenna on 15 meters without a tuner.
I added the 30 meter coil kit a couple months ago. The minimum SWR in this case is around 2. You'll need a tuner if you need lower SWR on 30 meters. But one of the first contacts I made after installing the 30 meter coil was Chagos Island. So it definitely works.