Re: Topband: Polyphaser
Polyphaser made a tester. http://wrblock.com/WRBproducts/DIGIfist/DigiFIST.html Possibly a land mobile shop in your area has one. Essentially they generated low current, high voltage until the tube fired. Perhaps it is different with HF, but in my land mobile experience, if the supressor was damaged, either it was shorted, or obvious damage was present when disassembled. Their antenna protectors have significant attenuation when used outside the rated frequency range. Art On Sun, Mar 1, 2015 at 7:17 AM, Greg Wilson n...@windstream.net wrote: Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Polyphaser
They also made an earlier version that had an analog meter. It would indicate the clamping voltage. Typical failure mode for the Polyphaser is an open gas tube that doesn't clamp... You loose protection and don't know it... I've also been told they also have a shelf life and at times the clamping voltage can decrease causing them to clamp at too low a voltage which wouldn't be a good thing in TX system use. Cecil K5DL Sent using recycled electrons. On Mar 1, 2015, at 4:37 PM, Art Snapper a...@nk8x.net wrote: Polyphaser made a tester. http://wrblock.com/WRBproducts/DIGIfist/DigiFIST.html Possibly a land mobile shop in your area has one. Essentially they generated low current, high voltage until the tube fired. Perhaps it is different with HF, but in my land mobile experience, if the supressor was damaged, either it was shorted, or obvious damage was present when disassembled. Their antenna protectors have significant attenuation when used outside the rated frequency range. Art On Sun, Mar 1, 2015 at 7:17 AM, Greg Wilson n...@windstream.net wrote: Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: [Bulk] Improving low angle reception DX Eng 8 ele Circle RCV Array
Hi Doug, I also use passive verticals in my 350 foot diameter W8JI 8-circle array. Reliability has been excellent (no failures in three years) because there are no sensitive electronic components in the array, except for the relays at the center of the array. Many deer traverse my receiving antenna field day every day (they live in the wooded margins of the field), but I've never had a problem with them getting tangled in the top hat wires because they're attached to the tops of seven foot fence posts. I'd surprised if a 100 foot diameter triband 8-circle could be very effective on Topband. The 35 foot distance between verticals is so small (less than 25 degrees of phase) that almost the entire signal is cancelled. On the other hand, 70 foot spaced receiving verticals work well if phase and amplitudes are accurately controlled. The pattern of 1/4 wavelength spaced verticals is slightly worse, but its much less sensitive to amplitude and phase errors. Yes, directivity is significantly reduced for very high angle signals because the wavefront arrives at all of the verticals at nearly the same phase. 73 Frank W3LPL - Original Message - From: Doug Renwick ve...@sasktel.net To: Grant Saviers gran...@pacbell.net, W0MU Mike Fatchett w...@w0mu.com, topband@contesting.com Sent: Sunday, March 1, 2015 9:37:41 PM Subject: Re: Topband: [Bulk] Improving low angle reception DX Eng 8 ele Circle RCV Array Hmmm. I have had excellent success with that DXE 4- quare system. I use my own verticals and the only problem is deer catching the top hat string and bending the vertical. 70 ft baselines seems short as the recommended is 135 ft for 160m. I find it very forgiving as the system works even if the verticals are not tuned correctly. Best receive system ever for me. Sometimes too much directivity especially in a contest, if there can ever be too much. Doug -Original Message- My 4 sq DXE exhibits similar no directivity at times. I think it is high angle signals. I did add three 20 foot radials to each antenna, I don't think it matters what the vertical element is, a little better grounding is good. My soil is wet/swampy forest/grass mix and I don't think they made much difference. I put the radials along the square 70' baselines and pointing outward outside the square to minimize any coupling to the feedlines to the switch box in the center of the array. My BIG problem is an intermittent S9+40 noise generated within the array. Comes and goes, so it is very hard to troubleshoot. I've disconnected each antenna one by one, checked, cleaned and reseated every cable, varied the power supply voltage, had the DXE preamp in and out and not found it. VERY frustrating!! I did find the antenna amp pcb's had not been flux cleaned and at each F female connector a lot of corrosion products had built up. I think this is because of the sustained DC voltage on that connector. Removing the white crystalline gunk that went from F center to the 4 soldered legs made no difference. My next step is to take apart the switch box and see what is going on inside it. DXE won't provide schematics, but I did find the W8JI patent which I think is what DXE is selling. It's a very good antenna IMO, but DXE needs to have better QC. Residual flux is bad and although the antenna enclosures are well made, they aren't water tight. Probably the boards should be conformal coated given the WX exposure, but that makes them harder to fix. Grant KZ1W On 3/1/2015 10:52 AM, W0MU Mike Fatchett wrote: I just recently hooked up my 8 ele rcv array and I was not too sure if it was working correctly. I will need to do some maintenance and checking when the snow is gone to make sure each element is working right. I chose the 160/80/40m which is close to 50 ft radius circle. I may opt to make it bigger if the area I have will allow. Last night in the NA QP RTTY contest the array seemed to be working fine and was quite directional on stateside signals on 40 and 80. I am seeing directivity on 160 with local broadcast stations. I was listening to the 3G0ZV station last night on 80 and he had a good signal. His signal did not seem to change much when I changed directions on the array. I was unable to work him though :( But that is an Xmit antenna issue. The array is placed over what it probably poor sandy soil. W3LPL mention in some of his talks that he was adding some radials to his receive array. His elements are a bit different than the DX Eng antennas so I don't know if this would help the DXE elements. My feeling is that the array could use some improvement in the low angle reception. I feel that it should hear better to Europe and Africa When I had just the 4 SQ Array up in Montana it was like night and day. EU Signals that were not copyable on the 80 xmit antenna were perfectly copyable on the 4 sq array. I am not seeing that
Re: Topband: DXCC Program Integrity
Maybe so Anthony but I distinctly recall attending a a IARU Region 2 conference some years ago in Ocho Rios, Jamaica and I was amazed at how many people from HQ along with their wives or partners that were booked in the 5 Star hotel where the conference was being held. It was almost like HQ was left with just the clerical staff. Some members of the ARRL travel often and to far away places with strange sounding names. Considering that there is an ARRL booth at every major and many minor ham-fests and that there is one every couple of weeks, there can be little doubt that league personnel do very well in frequent flyer miles and don't lodge at a Motel 6 during the event. Since the ARRL has a DXCC Desk as they call it, I wonder if they have a travel desk as well. Herb Schoenbohm, KV4FZ On 3/1/2015 2:07 PM, Anthony Scandurra wrote: I don't see ARRL staff pulling down six figure salaries, driving expensive cars, or living in mansions. Why do we always assume there is an ulterior and possibly malicious motive? The inescapable fact is that the ARRL needs funds to fight for us in Washington. The ARRL is not perfect, but no organization is. If you don't want to participate in DXCC because you think it is corrupt, then don't! No one is holding a gun to your head. 73, Tony K4QE _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Polyphaser
When I test things like that, I high pot them with a home made tester. Things like this are not difficult to make. You can buy a surplus HV power supply used to ionize air for a few bucks, and stick it in a box with a meter on it. You don't need to get fancy, just check it for breakdown voltage. If it is bad, the breakdown voltage will be way off. Ameritron gets about 5-10 customers a year where gas tubes in lightning protection go bad. They break down early. The result of that is an amplifier can get up to a few hundred watts or more, and then *wham* the feedline shorts! This is always great on parts. I don't have a single GDT in my TX system, although I've tried them in my RX systems out in switch boxes near antennas. I have mixed results using low voltage GDT devices to protect relays and stuff. I have no damage at all in the house without them. 73 Tom - Original Message - From: Art Snapper a...@nk8x.net To: Greg Wilson n...@windstream.net Cc: 160 topband@contesting.com Sent: Sunday, March 01, 2015 5:37 PM Subject: Re: Topband: Polyphaser Polyphaser made a tester. http://wrblock.com/WRBproducts/DIGIfist/DigiFIST.html Possibly a land mobile shop in your area has one. Essentially they generated low current, high voltage until the tube fired. Perhaps it is different with HF, but in my land mobile experience, if the supressor was damaged, either it was shorted, or obvious damage was present when disassembled. Their antenna protectors have significant attenuation when used outside the rated frequency range. Art On Sun, Mar 1, 2015 at 7:17 AM, Greg Wilson n...@windstream.net wrote: Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4800 / Virus Database: 4257/9209 - Release Date: 03/01/15 _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Polyphaser
Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Polyphaser
I don't know if the policy is still in place, but I remember that Polyphaser used to offer free testing of their products if you sent them back to the factory. Words about it were buried somewhere in their catalog, and I used the service many years ago when I was about to put one of their old coax arrestors back into service. Testing them yourself can be difficult, because it requires a high-voltage transient generator with known waveform characteristics. They're not too difficult to build, but sending a questionable part back to the factory is the best option for most of us. 73, Brad KV5V On Sun, Mar 1, 2015 at 6:17 AM, Greg Wilson n...@windstream.net wrote: Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Question...
On 2015-02-27, at 4:04 PM, mstang...@comcast.net wrote: Eddy, You do have a computer in the shack. You are an internet operator. Ham radio was one of the first forms of social media. We used to discuss operating and contesting issues on the air with our nets. We replaced the radio social media with internet groups and chat rooms. I bet you're like me and spend more time on internet groups that on the air. We have met the enemy and it us. Mike N2MS Hi Mike, Yes, that is quite true: lately I probably spend more time in front of the computer, than I do in front of the rig. I keep telling myself that it's merely a phase I'm going through, but on-the-air QSOs just don't seem like what they used to be. Seem to be more challenging interesting encounters people on-line, than on-the-air, of late. ~73~ de Eddy VE3CUI - VE3XZ _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling Ground and losses
Reply to W8JI post of Sat, 28 Feb 2015 19:14:07 -0500: The source of the r-f current flowing on buried radials is the r-f current flowing in the earth as a result of radiation from the vertical monopole. (etc) It seems to me that answer ignores other effects. 1.) If we remove the earth, the radials still have current. Yes, but then the origin of that current is via a direct, metallic path back to the 2nd terminal of the source (transmitter), using either balanced or coaxial transmission line. That operating configuration is different than when the radials are buried. 2.) If we place a conductor almost anywhere near any antenna, connected or not, it has current. If the wire is long and at 45 degrees or less, it can have very high current. But if those conductors are not buried, then the source of that current did not incur losses by traveling from the monopole to, and through the lossy earth around the base of the monopole -- to reach those radials. 3.) With the same applied power, a single radial in earth, despite being in the same dirt, has more current than the same radial with just one opposing radial. It's collecting from the same dirt. A single buried radial may have more current as you suggest (I'd have to model this), but that might be expected because a relatively small amount of the earth current flowing near the location where an opposing radial might have been can then collected by the remaining radial. No doubt the total current collected using both radials in this scenario is greater than when using either one of them, alone. 4.) Groundplanes still have current in radials See comment to 1.) above. Reply to KR9U post of Sat, 28 Feb 2015 21:23:50 -0500: ... If I add an imperfect ground with the radial buried just below the ground, I would expect that the efficiency of the antenna would drop. NEC4 shows it loses about 10 dB vs. free space, with about 6 dB of directivity in the direction of the radial wire using average ground. If I use dry sandy ground, then we gain back about 3 dB with a very similar pattern. ... Wouldn't that tend to show that a monopole system using a very high-loss ground plane should have greater gain than when driven against a very low-loss ground plane? Given that your NEC4 model is a 160-meter monopole system and other things equal, what does it show when only one 0.5-meter radial wire is used, and it is buried several centimeters below the surface of 0.1 mS/m d.c. 5 earth? If you are correct, then we should all be using uninsulated wires for radials. ?? EM radiation/current passes through the insulation of buried radial wires as easily as it does through the insulation of aerial wires. R. Fry _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: [Bulk] Improving low angle reception DX Eng 8 ele Circle RCV Array
Hmmm. I have had excellent success with that DXE 4- quare system. I use my own verticals and the only problem is deer catching the top hat string and bending the vertical. 70 ft baselines seems short as the recommended is 135 ft for 160m. I find it very forgiving as the system works even if the verticals are not tuned correctly. Best receive system ever for me. Sometimes too much directivity especially in a contest, if there can ever be too much. Doug -Original Message- My 4 sq DXE exhibits similar no directivity at times. I think it is high angle signals. I did add three 20 foot radials to each antenna, I don't think it matters what the vertical element is, a little better grounding is good. My soil is wet/swampy forest/grass mix and I don't think they made much difference. I put the radials along the square 70' baselines and pointing outward outside the square to minimize any coupling to the feedlines to the switch box in the center of the array. My BIG problem is an intermittent S9+40 noise generated within the array. Comes and goes, so it is very hard to troubleshoot. I've disconnected each antenna one by one, checked, cleaned and reseated every cable, varied the power supply voltage, had the DXE preamp in and out and not found it. VERY frustrating!! I did find the antenna amp pcb's had not been flux cleaned and at each F female connector a lot of corrosion products had built up. I think this is because of the sustained DC voltage on that connector. Removing the white crystalline gunk that went from F center to the 4 soldered legs made no difference. My next step is to take apart the switch box and see what is going on inside it. DXE won't provide schematics, but I did find the W8JI patent which I think is what DXE is selling. It's a very good antenna IMO, but DXE needs to have better QC. Residual flux is bad and although the antenna enclosures are well made, they aren't water tight. Probably the boards should be conformal coated given the WX exposure, but that makes them harder to fix. Grant KZ1W On 3/1/2015 10:52 AM, W0MU Mike Fatchett wrote: I just recently hooked up my 8 ele rcv array and I was not too sure if it was working correctly. I will need to do some maintenance and checking when the snow is gone to make sure each element is working right. I chose the 160/80/40m which is close to 50 ft radius circle. I may opt to make it bigger if the area I have will allow. Last night in the NA QP RTTY contest the array seemed to be working fine and was quite directional on stateside signals on 40 and 80. I am seeing directivity on 160 with local broadcast stations. I was listening to the 3G0ZV station last night on 80 and he had a good signal. His signal did not seem to change much when I changed directions on the array. I was unable to work him though :( But that is an Xmit antenna issue. The array is placed over what it probably poor sandy soil. W3LPL mention in some of his talks that he was adding some radials to his receive array. His elements are a bit different than the DX Eng antennas so I don't know if this would help the DXE elements. My feeling is that the array could use some improvement in the low angle reception. I feel that it should hear better to Europe and Africa When I had just the 4 SQ Array up in Montana it was like night and day. EU Signals that were not copyable on the 80 xmit antenna were perfectly copyable on the 4 sq array. I am not seeing that on the 8 ele array. Conditions are always different so maybe it is fine but condx have been poor? Thanks for your suggestions in advance! --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling Ground and losses
If the total energy flowing into the monopole system with buried radials is dictated only by its hard-wired connection through the transmission line back to the transmitter, then what is accounting for the reduction of its radiated power? Nothing I said even remotely implies loss would be the same as things are changed, so the question or exercise is completely meaningless to the topic. I said the system is complex. I said radial current comes from more than one cause. I said it is far more than just a simple transference of current from soil to the radials. The radials are directly exposed to antenna fields. The radials are directly connected to the antenna feedline. If they are anywhere near soil or in soil, they are coupling to the soil. The soil is part of the system. A fence near the radials is part of the system. Unconnected wires are part of the system. A lake or ocean near the antenna is part of the system. It is a huge mix of things interacting, not just a boy and his radial, with the radial collecting currents only from the soil. By definition, soil or not, the radials have current. By definition, connected to the feedpoint or not, the radials (like any conductor around an antenna) will have current. But if that isn't enough, the field strength change of a model doesn't even prove what physically happens. The model just estimates or calculates a result. It might be spot on, but it just is a calculated summary of results of many things. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Polyphaser
Polyphaser made a test box for a few years...model was F.I.S.T. 4. Worked really well.. Watch ebay...they may turn up there at times. Cecil K5DL Sent using recycled electrons. On Mar 1, 2015, at 5:27 PM, Tom W8JI w...@w8ji.com wrote: When I test things like that, I high pot them with a home made tester. Things like this are not difficult to make. You can buy a surplus HV power supply used to ionize air for a few bucks, and stick it in a box with a meter on it. You don't need to get fancy, just check it for breakdown voltage. If it is bad, the breakdown voltage will be way off. Ameritron gets about 5-10 customers a year where gas tubes in lightning protection go bad. They break down early. The result of that is an amplifier can get up to a few hundred watts or more, and then *wham* the feedline shorts! This is always great on parts. I don't have a single GDT in my TX system, although I've tried them in my RX systems out in switch boxes near antennas. I have mixed results using low voltage GDT devices to protect relays and stuff. I have no damage at all in the house without them. 73 Tom - Original Message - From: Art Snapper a...@nk8x.net To: Greg Wilson n...@windstream.net Cc: 160 topband@contesting.com Sent: Sunday, March 01, 2015 5:37 PM Subject: Re: Topband: Polyphaser Polyphaser made a tester. http://wrblock.com/WRBproducts/DIGIfist/DigiFIST.html Possibly a land mobile shop in your area has one. Essentially they generated low current, high voltage until the tube fired. Perhaps it is different with HF, but in my land mobile experience, if the supressor was damaged, either it was shorted, or obvious damage was present when disassembled. Their antenna protectors have significant attenuation when used outside the rated frequency range. Art On Sun, Mar 1, 2015 at 7:17 AM, Greg Wilson n...@windstream.net wrote: Does anyone know how to test a Polyphaser to know if it is still good? I have some that have seen some lightning storms and was wondering if they are still doing the job. Thanks, Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4800 / Virus Database: 4257/9209 - Release Date: 03/01/15 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling Ground and losses
Richard-- Is it conventional to compare the surface wave fields at a distance so near the Radial length and the wave length? 0.1 km Sounds like a lot, but it is only 100m, which is low, in Lambda terms.. Bill--W4BSG -Original Message- From: Richard Fry Sent: Sunday, March 01, 2015 12:08 PM To: topband@contesting.com Subject: Re: Topband: Modeling Ground and losses The feedpoint connection, in all cases of vertical antennas, whether the system is shunt fed or series fed, or even if it is an end-fed half wave, ties one feed terminal to the ground or counterpoise system. It has to be that way, and the current out into that counterpoise (whatever the counterpoise is) has to be equal to the common mode current at the junction flowing up into the radiator. The link below leads to a NEC4 comparison of a 1/4WL vertical monopole using four 1/4WL radial wires at 90-deg horizontal intervals. In one case the radials are buried. In the other case they (and the monopole) are elevated 1 meter above the earth, and not connected to the earth by any metallic path. Applied power in both cases is 100 watts, and earth conductivity in both cases is 5 mS/m, d.c.5. The surface wave fields at 0.1 km from these two configurations differ by about 1.15 dB, which means that their radiated powers differ by about 30%. If the total energy flowing into the monopole system with buried radials is dictated only by its hard-wired connection through the transmission line back to the transmitter, then what is accounting for the reduction of its radiated power? http://s20.postimg.org/453nz5vn1/160_M_QTR_WV_MONOPOLE_Flds.jpg R. Fry _ Topband Reflector Archives - http://www.contesting.com/_topband --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: [Bulk] Improving low angle reception DX Eng 8 ele Circle RCV Array
I was just re reading the DXE manual on the circle array and they discuss adding 15 ft radials of 10 to 15 feet or adding a couple of ground rods per antenna. The first thing I will do is see if I can grow the array another 30ish feet in diameter so it works best on 80 and will work but not as well on 160. Now to wait for the snow to melt! W0MU _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Inverted L height vs. length.
24 hours and even not one comment? What if I had a BOG for RX, buried, uninsulated radials and had worked K1N with it during my move into a Brave New World? Maybe I really should've said I was renting the station out for hire to offshore stns only, to be used to work rare countries, during contests for DXCC credits to put them at the top of the honor roll... ;-) Sorry for asking a pretty reasonable non-emotionally charged question (how foolish of me) Mike, An Inverted L challenged guy in the snowbelt of NB VE9AA Mike, Coreen Corey Keswick Ridge, NB From: Mike Coreen Smith VE9AA [mailto:ve...@nbnet.nb.ca] Sent: February 28, 2015 2:40 PM To: 'topband@contesting.com' Subject: Inverted L height vs. length. de VE9AA I know inverted L's have been hashed out quite a few times on this list, and I have gleaned some knowledge. At my previous QTH I had a 5/16th WL one which seemed to work tons better than my current one, even though I was not up over 40' high. As it happens, on my current property I don't have any towers, nor tall trees so I have a general question. As far as a 127' inverted L goes, do I have anything to gain by sloping the vertical portion of the wire slightly up to a short treetop, vs. going nearly vertical, then the rest horizontal? Example: I have a 35-40' tree nearish to where my coax exits the ground from an underground run. I slope it up so essentially I have likely close to 50' of vertical then the remainder meanders through some shorter treetops and comes back to ground rather quickly (unfortunately it's more an inverted U than L). I have a few thousand feet of radials mostly in the southern portion of the field under the horizontal section. A 800pf Cap is at the base and my SWR is around 50-60Kcs at the 2.1:1 pts. I seem to do quite well into w1,2,3,4,8 and at times western EU/Carib. Anything outside that sucks. That tells me I probably have gobs of high angle radiation. Have I anything to gain by putting the coax directly under the tree, going perfectly vertical for 37-ish feet, then, sadly, pretty much down to the ground for the horizontal section same as the original? (hope this ascii art works) Ie: This is what I am doing now (wire is around 65*-70* vertical or so_) ___ /\ /\ / \ but I wonder of this is any better __ _ |\ | \ |\ Lastly, I could go farther away from the tree and try to get 80-90' of sloping wire (likely closer to 45*) and then have the remainder droop itself back to Earth. _ _ _ _ / \ / \ / \ / Anyone have a skyhook for sale? Thanks for any insight. Mike VE9AA FN66na @ 660' ASL.rocky ridgetop. Mike, Coreen Corey Keswick Ridge, NB _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Inverted L height vs. length.
I have used one inverted L and the horses wiped it out a few years ago. I had about 70 ft of vertical and the rest horizontal. I am not sure how much interaction the tree will have if you run the wire next to it. The end sloping down will affect the match if my memory serves. If that is what you can do, what other choices are there? I would say that top loaded vertical might be a better option as they both require radials right? Mike W0MU On 3/1/2015 12:19 PM, Mike Coreen Smith VE9AA wrote: 24 hours and even not one comment? What if I had a BOG for RX, buried, uninsulated radials and had worked K1N with it during my move into a Brave New World? Maybe I really should've said I was renting the station out for hire to offshore stns only, to be used to work rare countries, during contests for DXCC credits to put them at the top of the honor roll... ;-) Sorry for asking a pretty reasonable non-emotionally charged question (how foolish of me) Mike, An Inverted L challenged guy in the snowbelt of NB VE9AA Mike, Coreen Corey Keswick Ridge, NB From: Mike Coreen Smith VE9AA [mailto:ve...@nbnet.nb.ca] Sent: February 28, 2015 2:40 PM To: 'topband@contesting.com' Subject: Inverted L height vs. length. de VE9AA I know inverted L's have been hashed out quite a few times on this list, and I have gleaned some knowledge. At my previous QTH I had a 5/16th WL one which seemed to work tons better than my current one, even though I was not up over 40' high. As it happens, on my current property I don't have any towers, nor tall trees so I have a general question. As far as a 127' inverted L goes, do I have anything to gain by sloping the vertical portion of the wire slightly up to a short treetop, vs. going nearly vertical, then the rest horizontal? Example: I have a 35-40' tree nearish to where my coax exits the ground from an underground run. I slope it up so essentially I have likely close to 50' of vertical then the remainder meanders through some shorter treetops and comes back to ground rather quickly (unfortunately it's more an inverted U than L). I have a few thousand feet of radials mostly in the southern portion of the field under the horizontal section. A 800pf Cap is at the base and my SWR is around 50-60Kcs at the 2.1:1 pts. I seem to do quite well into w1,2,3,4,8 and at times western EU/Carib. Anything outside that sucks. That tells me I probably have gobs of high angle radiation. Have I anything to gain by putting the coax directly under the tree, going perfectly vertical for 37-ish feet, then, sadly, pretty much down to the ground for the horizontal section same as the original? (hope this ascii art works) Ie: This is what I am doing now (wire is around 65*-70* vertical or so_) ___ /\ /\ / \ but I wonder of this is any better __ _ |\ | \ |\ Lastly, I could go farther away from the tree and try to get 80-90' of sloping wire (likely closer to 45*) and then have the remainder droop itself back to Earth. _ _ _ _ / \ / \ / \ / Anyone have a skyhook for sale? Thanks for any insight. Mike VE9AA FN66na @ 660' ASL.rocky ridgetop. Mike, Coreen Corey Keswick Ridge, NB _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Inverted L height vs. length.
I can speculate that your mail box would be overflowing and you could retire comfortably especially if you had a 160m station that worked. Sri Tom, I couldn't resist having some fun. Doug -Original Message- 24 hours and even not one comment? Maybe I really should've said I was renting the station out for hire to offshore stns only, to be used to work rare countries, during contests for DXCC credits to put them at the top of the honor roll... VE9AA Mike, Coreen Corey Keswick Ridge, NB --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling Ground and losses
The source of the r-f current flowing on buried radials is the r-f current flowing in the earth as a result of radiation from the vertical monopole. (etc) It seems to me that answer ignores other effects. 1.) If we remove the earth, the radials still have current. Yes, but then the origin of that current is via a direct, metallic path back to the 2nd terminal of the source (transmitter), using either balanced or coaxial transmission line. I doubt any system is 100% pure with a boundary condition like a hard switch. Dirt is not the same everywhere, even at one location. It probably is almost never the same at the surface as it is a few inches down. Arbitrarily declaring the method current gets into the wire is a single method determined entirely by contact or no contact is completely illogical. The feedpoint connection, in all cases of vertical antennas, whether the system is shunt fed or series fed, or even if it is an end-fed half wave, ties one feed terminal to the ground or counterpoise system. It has to be that way, and the current out into that counterpoise (whatever the counterpoise is) has to be equal to the common mode current at the junction flowing up into the radiator. It can't be any other way. Contact with the earth isn't like suddenly flipping a light switch, where all of a sudden all of the current is magically collected from the dirt all around the antenna, and then moving the wire .01 wavelengths up suddenly flips the switch the other way. The only true case I can think of where virtually all of the current is returned from the soil would be where the radial wire is buried several soil skin depths below the surface. We can certainly have creative license to **say** it is collected from the soil for any buried radial, but it pretty clearly isn't factual unless the wire is infinitely deep in the soil so far as skin depth goes. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 Tower on 80
This is why wide broadcast towers, even 1/2 wave tall towers, can have reasonably low impedances at the base.² Agreed. I have found it very difficult to model accurate complex base Z measurements of wide broadcast towers (i.e., low height/diam. ratio) that are of the 180-195 degree variety - even with NEC4.2. This is one of NEC¹s more significant limitations. In some of these cases, lighting systems and any STL transmission lines play a part in the true base Z. Still, I routinely get results that show much higher base Z in the model than actual measured base Z results. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: DXCC Program Integrity
This one interesting sentence, made in another thread, may be at the root of much of the disagreement expressed in the last few days with regards to DXCC. It does cause one to wonder why the award exists at all. If DXCC only matters to the recipient, why wouldn't their logbook serve the same purpose? For some, it does. What added gratification does that extra piece of paper provide? It's not exactly free. What makes the DXCC countries list so special -- why not use some other list? Why did ARRL go to great pains to make LoTW more challenging than online banking? Why are individuals disqualified from the program if the award only affects *them*? Why do we have card checkers that look for that dot between the 1 and the 8 like the guy looking for a hanging chad with a magnifying glass? Finally, what does it mean for the League to call DXCC the premier operating award then turn up their hands and basically say we can't enforce any of this it's up to you guys? Larry K5RK Larry, This all just life no matter what we do. If we base our self-worth, or determine the worth of others by what **we** like or what we think they should do, we are destined to be grouchy unhappy people who spend a lot of time making ourselves and others unhappy. It is this way in car shows, it is this way in automotive racing. It is this way in gaming and in sculpture and art. The DXCC is the DXCC as the rule written for DXCC apply. If someone does not like the rules as written, they can try to change the rules or go find something else they like better. In my opinion, and what makes me uncomfortable and ruins the spirit, is trying to disparage others because we don't happen to like the way the rules are written. As for cheating, which really means breaking a rule (not what we might personally WANT a rule to be), that will always go on. The best we can do is try to minimize it by careful thought. We seem to be becoming an increasingly angry society who like to not see anyone else having fun. We make extreme statements, invent conspiracies, and intentionally take things out of context just to be whining drama queens or professional curmudgeons. The weirdest part of it all is we worry about and get all dramatic about small meaningless stuff, while we do nothing to rationally work on real problems. I think maybe we are all getting old, and getting some of that infamous Brooklyn syndrome. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: DXCC Program Integrity
Larry I admire your ability to see past the 'smoke and mirrors' and expose the hypocrisy of the ARRL DXCC program. What you have said is true. The ARRL speaks out of both corners of their mouth. There will be others who will object to you exposing the DXCC program and there will be others who wish to change the subject. Some will find the truth unacceptable. Doug -Original Message- The integrity of the program is irrelevant This one interesting sentence, made in another thread, may be at the root of much of the disagreement expressed in the last few days with regards to DXCC. It does cause one to wonder why the award exists at all. If DXCC only matters to the recipient, why wouldn't their logbook serve the same purpose? For some, it does. What added gratification does that extra piece of paper provide? It's not exactly free. What makes the DXCC countries list so special -- why not use some other list? Why did ARRL go to great pains to make LoTW more challenging than online banking? Why are individuals disqualified from the program if the award only affects *them*? Why do we have card checkers that look for that dot between the 1 and the 8 like the guy looking for a hanging chad with a magnifying glass? Finally, what does it mean for the League to call DXCC the premier operating award then turn up their hands and basically say we can't enforce any of this it's up to you guys? Larry K5RK --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: DXCC Program Integrity
The integrity of the program is irrelevant This one interesting sentence, made in another thread, may be at the root of much of the disagreement expressed in the last few days with regards to DXCC. It does cause one to wonder why the award exists at all. If DXCC only matters to the recipient, why wouldn't their logbook serve the same purpose? For some, it does. What added gratification does that extra piece of paper provide? It's not exactly free. What makes the DXCC countries list so special -- why not use some other list? Why did ARRL go to great pains to make LoTW more challenging than online banking? Why are individuals disqualified from the program if the award only affects *them*? Why do we have card checkers that look for that dot between the 1 and the 8 like the guy looking for a hanging chad with a magnifying glass? Finally, what does it mean for the League to call DXCC the premier operating award then turn up their hands and basically say we can't enforce any of this it's up to you guys? Larry K5RK _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Question...
Eddy, Unfortunately many technical nets have been replaced by group discussions. I participate in the group discussions but I enjoy talking about station and antenna setups and hearing the results of the experimentation on the air. My 160 inverted L came down during the first snowfall of the season. I'm waiting for the ice and snow to melt before so that I can fix it. Hopefully I'll meet you on the air. Mike N2MS - Original Message - From: Eddy Swynar deswy...@xplornet.ca To: mstang...@comcast.net Cc: topband@contesting.com Sent: Sun, 01 Mar 2015 14:34:52 - (UTC) Subject: Re: Topband: Question... On 2015-02-27, at 4:04 PM, mstang...@comcast.net wrote: Eddy, You do have a computer in the shack. You are an internet operator. Ham radio was one of the first forms of social media. We used to discuss operating and contesting issues on the air with our nets. We replaced the radio social media with internet groups and chat rooms. I bet you're like me and spend more time on internet groups that on the air. We have met the enemy and it us. Mike N2MS Hi Mike, Yes, that is quite true: lately I probably spend more time in front of the computer, than I do in front of the rig. I keep telling myself that it's merely a phase I'm going through, but on-the-air QSOs just don't seem like what they used to be. Seem to be more challenging interesting encounters people on-line, than on-the-air, of late. ~73~ de Eddy VE3CUI - VE3XZ _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 Tower on 80
Hi all, I have a 90 foot Rohn 25 tower with an insulated base and insulated guy wire sections for top loading ,base fed for 160 meters. It work great ,but I would like to use it on 80 meters as well. The 3 ideas I have considered are voltage feed at the base with a resonant LC network at the base, but I am a little worried about the voltages present at legal limit power. Second idea,disconnect the top loading and put a trap between the top loading and the tower to divorce the top loading on eighty then an L network at the base for 80. Third idea, run a wire as a sloper either a quarter wave fed against ground or a 1/2 wave dipole from the tower. Any thoughts or alternative ideas would be greatly appreciated. Hi Glen, Every antenna is also a transmission line. Every conductor making up an antenna has a surge impedance. That surge impedance, along with several other factors, determines the base voltage. If the conductor is uniform size, lossless, not coupled very well to space, and infinitely thin, the voltage at some points along the length can extremely high. As it is made thicker or loss is added, voltage greatly decreases no matter what the length. This is why wide broadcast towers, even 1/2 wave tall towers, can have reasonably low impedances at the base. A 90 foot tower against lossless perfect ground, with hat wires to make it resonant on 160 meters, has about 2kV peak base voltage at 1500 watts on 80 meters. The base impedance is only around 1000-1500 ohms. This is no worse than voltages typically encountered in traps of trap Yagi antennas, so it isn't astronomical. It won't be anything at all like feeding a vertical #38 AWG wire for voltage or impedance. :) 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: DXCC Program Integrity
I think the ARRL does many good things for Amateur Radio. They are also involved in things that are good for them and not so much for us. Their latest call for comments is directly related to the RM11708 issue. The DXCC program history is certainly not a beacon of purity and transparency is it? Some guy operating a remote station to work people is nothing compared to some of the things that have gone on in the program. The Centennial Award last year got people on the air and working other people which is a good thing. They also sold a boat load of LOTW credits and awards. The challenge Award Sells lots of LOTW credits and more plaques. I have no problem with it. The plaque is nice and it is fun to chase all the band mode combos and it has promoted more activity. Was the primary goal to get more people on the air or sell more stuff? Mike W0MU On 3/1/2015 10:27 AM, Doug Renwick wrote: Larry I admire your ability to see past the 'smoke and mirrors' and expose the hypocrisy of the ARRL DXCC program. What you have said is true. The ARRL speaks out of both corners of their mouth. There will be others who will object to you exposing the DXCC program and there will be others who wish to change the subject. Some will find the truth unacceptable. Doug -Original Message- The integrity of the program is irrelevant This one interesting sentence, made in another thread, may be at the root of much of the disagreement expressed in the last few days with regards to DXCC. It does cause one to wonder why the award exists at all. If DXCC only matters to the recipient, why wouldn't their logbook serve the same purpose? For some, it does. What added gratification does that extra piece of paper provide? It's not exactly free. What makes the DXCC countries list so special -- why not use some other list? Why did ARRL go to great pains to make LoTW more challenging than online banking? Why are individuals disqualified from the program if the award only affects *them*? Why do we have card checkers that look for that dot between the 1 and the 8 like the guy looking for a hanging chad with a magnifying glass? Finally, what does it mean for the League to call DXCC the premier operating award then turn up their hands and basically say we can't enforce any of this it's up to you guys? Larry K5RK --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: DXCC Program Integrity
I don't see ARRL staff pulling down six figure salaries, driving expensive cars, or living in mansions. Why do we always assume there is an ulterior and possibly malicious motive? The inescapable fact is that the ARRL needs funds to fight for us in Washington. The ARRL is not perfect, but no organization is. If you don't want to participate in DXCC because you think it is corrupt, then don't! No one is holding a gun to your head. 73, Tony K4QE _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling Ground and losses
The feedpoint connection, in all cases of vertical antennas, whether the system is shunt fed or series fed, or even if it is an end-fed half wave, ties one feed terminal to the ground or counterpoise system. It has to be that way, and the current out into that counterpoise (whatever the counterpoise is) has to be equal to the common mode current at the junction flowing up into the radiator. The link below leads to a NEC4 comparison of a 1/4WL vertical monopole using four 1/4WL radial wires at 90-deg horizontal intervals. In one case the radials are buried. In the other case they (and the monopole) are elevated 1 meter above the earth, and not connected to the earth by any metallic path. Applied power in both cases is 100 watts, and earth conductivity in both cases is 5 mS/m, d.c.5. The surface wave fields at 0.1 km from these two configurations differ by about 1.15 dB, which means that their radiated powers differ by about 30%. If the total energy flowing into the monopole system with buried radials is dictated only by its hard-wired connection through the transmission line back to the transmitter, then what is accounting for the reduction of its radiated power? http://s20.postimg.org/453nz5vn1/160_M_QTR_WV_MONOPOLE_Flds.jpg R. Fry _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Improving low angle reception DX Eng 8 ele Circle RCV Array
I just recently hooked up my 8 ele rcv array and I was not too sure if it was working correctly. I will need to do some maintenance and checking when the snow is gone to make sure each element is working right. I chose the 160/80/40m which is close to 50 ft radius circle. I may opt to make it bigger if the area I have will allow. Last night in the NA QP RTTY contest the array seemed to be working fine and was quite directional on stateside signals on 40 and 80. I am seeing directivity on 160 with local broadcast stations. I was listening to the 3G0ZV station last night on 80 and he had a good signal. His signal did not seem to change much when I changed directions on the array. I was unable to work him though :( But that is an Xmit antenna issue. The array is placed over what it probably poor sandy soil. W3LPL mention in some of his talks that he was adding some radials to his receive array. His elements are a bit different than the DX Eng antennas so I don't know if this would help the DXE elements. My feeling is that the array could use some improvement in the low angle reception. I feel that it should hear better to Europe and Africa When I had just the 4 SQ Array up in Montana it was like night and day. EU Signals that were not copyable on the 80 xmit antenna were perfectly copyable on the 4 sq array. I am not seeing that on the 8 ele array. Conditions are always different so maybe it is fine but condx have been poor? Thanks for your suggestions in advance! -- Mike W0MU _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: [Bulk] Improving low angle reception DX Eng 8 ele Circle RCV Array
My 4 sq DXE exhibits similar no directivity at times. I think it is high angle signals. I did add three 20 foot radials to each antenna, I don't think it matters what the vertical element is, a little better grounding is good. My soil is wet/swampy forest/grass mix and I don't think they made much difference. I put the radials along the square 70' baselines and pointing outward outside the square to minimize any coupling to the feedlines to the switch box in the center of the array. My BIG problem is an intermittent S9+40 noise generated within the array. Comes and goes, so it is very hard to troubleshoot. I've disconnected each antenna one by one, checked, cleaned and reseated every cable, varied the power supply voltage, had the DXE preamp in and out and not found it. VERY frustrating!! I did find the antenna amp pcb's had not been flux cleaned and at each F female connector a lot of corrosion products had built up. I think this is because of the sustained DC voltage on that connector. Removing the white crystalline gunk that went from F center to the 4 soldered legs made no difference. My next step is to take apart the switch box and see what is going on inside it. DXE won't provide schematics, but I did find the W8JI patent which I think is what DXE is selling. It's a very good antenna IMO, but DXE needs to have better QC. Residual flux is bad and although the antenna enclosures are well made, they aren't water tight. Probably the boards should be conformal coated given the WX exposure, but that makes them harder to fix. Grant KZ1W On 3/1/2015 10:52 AM, W0MU Mike Fatchett wrote: I just recently hooked up my 8 ele rcv array and I was not too sure if it was working correctly. I will need to do some maintenance and checking when the snow is gone to make sure each element is working right. I chose the 160/80/40m which is close to 50 ft radius circle. I may opt to make it bigger if the area I have will allow. Last night in the NA QP RTTY contest the array seemed to be working fine and was quite directional on stateside signals on 40 and 80. I am seeing directivity on 160 with local broadcast stations. I was listening to the 3G0ZV station last night on 80 and he had a good signal. His signal did not seem to change much when I changed directions on the array. I was unable to work him though :( But that is an Xmit antenna issue. The array is placed over what it probably poor sandy soil. W3LPL mention in some of his talks that he was adding some radials to his receive array. His elements are a bit different than the DX Eng antennas so I don't know if this would help the DXE elements. My feeling is that the array could use some improvement in the low angle reception. I feel that it should hear better to Europe and Africa When I had just the 4 SQ Array up in Montana it was like night and day. EU Signals that were not copyable on the 80 xmit antenna were perfectly copyable on the 4 sq array. I am not seeing that on the 8 ele array. Conditions are always different so maybe it is fine but condx have been poor? Thanks for your suggestions in advance! _ Topband Reflector Archives - http://www.contesting.com/_topband
