Re: Topband: To clamp or NOT...that IS the question
On 01/17/2014 09:51 PM, Tom W8JI wrote: Intermod is a function of the TOTAL voltage of all the signal sources at the point where the diodes are. This is why some systems work with diodes, and some systems completely fall apart. The problem can come from a hundred small signals, each signal far below threshold, or just one large signal near threshold. Impedance also matters, both in band and out-of-band. Indeed. I've had problems with ICE 196 receiver protectors for several years. I assume the intermod is generated by the diodes in those devices, though I do not know that for a fact. The problem occurs on nights when propagation is very good both in the AM BC band and shortwave in the 5-7 MHz range. I get some extremely strong SW BC stations on good nights. All are well below the threshold but the combined affect of many signals is too much. Removing the ICE 196 clears up the intermod, so I am reasonably certain that is where it is generated. I need to either find another way to protect my front end or use band pass filters. 73, Paul N1BUG _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: To clamp or NOT...that IS the question
On 01/18/2014 06:20 AM, N1BUG wrote: Indeed. I've had problems with ICE 196 receiver protectors for several years. I assume the intermod is generated by the diodes in those devices, though I do not know that for a fact. The problem occurs on nights when propagation is very good both in the AM BC band and shortwave in the 5-7 MHz range. I get some extremely strong SW BC stations on good nights. All are well below the threshold but the combined affect of many signals is too much. Removing the ICE 196 clears up the intermod, so I am reasonably certain that is where it is generated. I need to either find another way to protect my front end or use band pass filters. Sorry... I should have noted this is using Beverages +/- 600 feet long. 73, Paul N1BUG _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: on the webcam issue
Thanks Mike. Interesting video. It brings back memories of working ARRL 160 with a straight key back in the 1980s. I couldn't do much with my right arm for days after that. 73, Paul N1BUG On 01/02/2014 02:55 AM, w7...@juno.com wrote: I have been reading with great interest the different forms of person/computer assistance one can expect to get while operating a CW contest. Not wanting to be left out of this fray and realizing freedom of speech issues are at the core of this discussion, I set up a web cam (Sony DCSC-P41) at the station 160 meter operating position, and feel it is my responsibility to let anyone look at it if they wish. There has been no editing, the signals heard are real, and individual calls and station operating practices are laid out for all to experience. http://youtu.be/sXhhHo5BKnE I wish to offend no one. mike w7dra _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Stew Perry Streaming Audio
For some like myself who have never and will never be able to experience topband from other areas ore even other local stations, streaming audio can be of significant interest, be it contest or non contest. It adds another dimension of fun, discovery, and learning to the hobby. I see very little to no potential for abuse of streaming audio from a contest participant. Non-contest streaming could be a different matter, but frankly in today's world there is so much technology available for cheating that the means is always there for those who are going to do it. I don't believe a few stations streaming audio is going to change the playing field much. I personally have streamed audio/video from my station during 6 meter operation. There was a good deal of interest for reasons similar to those stated in my opening paragraph. Thus far I have hesitated to do it on 160 because there are so many who get upset about it. I wish we had some way to stream with a short built in delay - long enough to preclude using the stream as a remote receiver. Incredibly, I have not been able to find any way to do that. My solution has been to stream video along with the audio. The delay in video encoding and broadcast has been enough to make it virtually useless to anyone who might try to use it as a remote receiver. My blood pressure is lower since I accepted there are those who are going to cheat, that DX standings may not reflect what was done by fair means alone, and that there is nothing I can do about it. It wasn't an easy adaptation, but it was a healthy one. I won't comment on contest scores. I'm not enough of a competitive contester to have formed an opinion on the level of cheating that may ore may not take place. 73, Paul N1BUG _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Wideband interference
I think Jim and Barry both have valid points. Let me attempt to throw some perspective on it. For a ham faced with going out in the bitter cold to hunt down RFI, getting input and advice from others who have found the source of noise with similar sound or spectrum plots can help narrow down the likely source and save time in the field. There's certainly nothing wrong with that. On the other hand, if a ham approaches a professional working for a utility company (or whatever) about their RFI and says they believe it is coming from such and such a device based on the sound and spectrum plots, it may have a detrimental affect on the professional's estimate of the ham's approach and claims. It may affect their response to the problem. This isn't always going to be the case, of course, but it certainly can't hurt if the ham has already done some footwork to identify the source in a manner consistent with how it is done in professional circles. You want to make the best first impression you possibly can. The other issue that often comes up with hams is not having the portable equipment to track down a source, and budget concerns related to acquiring it. As a ham on a fixed income and extremely tight budget, I get this. I also get that there will be some reading this who are thinking I've got no clue whatsoever what a tight budget is. :-) That was me for many years. When I really started looking into cleaning up my RF environment, I realized the DF equipment had to be a priority, even though it meant downsizing my ham station and/or not replacing some gear that is badly outdated or on it last legs. I now consider the DF and RFI hunting equipment to be vital tools for survival in the modern RF jungle. I am personally experiencing a strong topband RFI issue that I haven't gone out to find. It will require a three mile walk with the relatively heavy and bulky DF equipment just to get to the likely source area, some walking to find it, and a three mile walk home after! In Maine that is brutal this time of year. On the other hand, even if I become 95% certain I knew what it is, I won't be calling a utility or other business/professional to report my RFI until I have been out to DF it myself. First impressions can be everything. This is just my opinion, of course. 73 -- Paul Kelley, N1BUG RFI Committee chair, Piscataquis Amateur Radio Club http://www.k1pq.org _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Easy-to-learn 160 contest logging program?
Since we haven't yet been asked to cease with this thread I'll throw my oar in the water. I know I will never win any contests with my station. Nevertheless I often enter with the intent of getting every contact I possibly can. It's not so much about competing, even with my own past efforts, as it is sharpening my operating skills. Improving my skills is a very powerful motivation. I find a major improvement during every contest I operate, and the faster I can run stations the greater the overall improvement. Hence, even though I know I won't be a winning contester, I want the best rate optimizing tools I can get. I've been using N1MM for several years. I am often a bit challenged getting new software set up but I found this one relatively painless. 73, Paul N1BUG _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: NOISE CANCELLERS
As always, Tom has done a great job educating us on this topic. I completely agree with everything he said about antenna selection for effective noise canceling. Unfortunately it isn't always possible to achieve the ultimate. In some cases it may be possible to achieve some improvement with much less than ideal antennas. I have a noise that I have been trying to locate for years. Despite many hours (better measured in days or weeks by now) out with DF equipment I have not been able to identify the source. In part due to the fact my 160 meter transmit antenna does a wonderful job of re-radiating this noise, I hear it to varying degrees in all of my 8 Beverage directions. Due to my lack of skill and/or adequate instrumentation to find the source or stop the tower from re-radiating, some other approach must be tried. It isn't possible to put up any more Beverages. Yesterday I erected a short vertical somewhat near my transmit antenna. It is a simple 24 foot whip with a single short ground rod. I fed it with a 900:50 ohm matching transformer and did not attempt to do any tuning or matching. Using this as the AUX or NOISE antenna with my MFJ-1026 noise canceler I am able to achieve a good null for all 8 Beverage directions. This isn't perfect but it does help. I will describe the limitations. In some directions my Beverages are in reverse mode and signal level is quite low due to loss in the WD-1A wire in transmission line mode. The noise is relatively low in these directions, so I am able to run the MAIN antenna gain at maximum and the AUX antenna gain at about 50 per cent of maximum. There seems to be little or no signal to noise degradation from the AUX antenna being omnidirectional. However, the noise floor of the MFJ-1026 is enough to raise the system noise floor and reduce signal to noise a small amount. This could probably be solved by using a preamp ahead of the MFJ-1026. I am not able to try that right now. In other directions, where the noise level on Beverages is very strong, I have to run the AUX antenna gain at maximum and reduce the MAIN antenna gain to get a good null. In this configuration, the AUX antenna does add considerable noise to the system. However, even with the described limitations, the setup allows improved signal to noise in each of the 8 directions, compared to using a Beverage alone with no ability to null the offending noise. This very simple setup is clearly better than nothing. It is often enough to make the difference between no copy and 100 per cent copy. My point is... If possible, follow Tom's advice about antennas! If not, don't give up. Try what you can. You might get lucky. 73, Paul N1BUG _ Topband Reflector
Re: Topband: Detuning/Grounding Xmit Antenna while on RX
Can someone explain why grounding the feed of a shunt fed tower prevents it from re-radiating noise? The tower is already grounded. I don't understand how grounding the coax port looking into the gamma or omega match accomplishes the goal. I've been trying to get my shunt fed tower to stop re-radiating noise into my Beverages for 7 years with NO success. I've been trying to detune a section of the tower by making a loop with capacitor as described in ON4UN's books. 73, Paul N1BUG _ Topband Reflector
Re: Topband: K9W
The first night they were on, K9W peaked 599 and a bit over here in central Maine around 0800z. Amazing! They were very readable for hours, but that was the peak. There was a secondary, much weaker peak at sunrise that morning. After that first night, conditions were never as good again. There were nights they were not readable at all, others they got up to 559, maybe 569 for short periods. This underscores a lesson I re-learned the hard way when I missed 3C0 and ZL9. On topband, you have got to lose some sleep and put some hours in the chair if you really want the DX. :-) 73, Paul N1BUG (happy to have worked W8A for # 281 this morning) On 11/15/2013 06:35 AM, Gary Smith wrote: Missed them, was trying at the wrong times I guess. Was listening at their Sun rise afterward, was up till 3AM several nights trying. guess I should have been listening at my SR. So here's W8A I'm listening for I'm not hearing them at my grayline but I hear plenty of others banging away for them. Hope this isn't a harbinger of this season for me on TB. 73, Gary KA1J Hoping to get K9W on top band tonight. I couldn't hear them last night but see they were on after I went to bed. I snooze, I lose... 73, Gary KA1J --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _ Topband Reflector --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _ Topband Reflector -- Paul Kelley, N1BUG RFI Committee chair, Piscataquis Amateur Radio Club http://www.k1pq.org _ Topband Reflector
Re: Topband: Local noise source identification
I realize this won't help but I have a similar noise. Mine is about 24 kHz wide and drifts up/down considerably more than yours. The drift seems related to outside temperature. Here's the real kicker: it goes away every year immediately upon the coming of snow cover, but does not return until mid-summer sometime. This has been happening for at least five years now. I've tracked it to a group of 4 or 5 houses on the other side of a river, about 1000 feet from (some of) my Beverages. Sidebar: With a portable receiver I can also detect it re-radiating from my 100 foot vertical, which is 1500 feet from the source. Good luck, and let us know if you find it. 73, Paul N1BUG On 11/09/2013 05:15 PM, Rick ve3mm wrote: I am looking for suggestions to help identify a local noise that I am experiencing on topband. It's characteristics are; - bandwidth approximately 15 kHz - amplitude relatively constant - centre frequency seems to vary in small steps over time, no real pattern. - right now the centre frequency is 1819 kHz, it moves up and down up to 7 or 8 kHz. - does not seem to be present during the day. At least not this afternoon. I shut down all of the circuits in my house other than my shack and it did not disappear. Has anyone experienced something similar? 73 Rick ve3mm _ Topband Reflector
Re: Topband: Power strip price break
Apologies for the second reply, to add: These come in lengths from 24 inches to 72 inches. All are built the same and are easily shortened as noted below. PS2408 PS3612 PS4816 PS6020 PS7224 The first two digits indicate the length in inches, the second pair the number of outlets. 73, Paul N1BUG On 10/15/2013 06:28 AM, N1BUG wrote: It looks like Wal-Mart matched Amazon's price to the penny. I recently bought two PS6020 strips for my new ham desk. Jim, are you sure about the MOV's? My understanding is that the PS series have no surge protection while the SS series does. By the way the PS series is very easy to shorten if you need a custom length as I did. The usual safety precautions and disclaimers apply. _ Topband Reflector
Re: Topband: Are stacked verticals feasible?
On 09/06/2013 09:26 AM, ZR wrote: I would think that at 6-12' spacing from the tower it would minimize interaction on 160 or 80? I don't know, Carl. I'll leave it to the experts. What I do know is I have made several attempts to erect a vertical for 80 meters near my 160 meter tower, using the same radial system. At 10 foot spacing from the tower, the base resistance of an 80 meter quarter wave vertical was less than 5 ohms. That to me suggests significant interaction with the tower. At 5 foot spacing the base resistance was less than 2 ohms! I don't have the data handy but I seem to recall having to adjust the length considerably from a quarter wavelength to cancel a reactive component. 73, Paul N1BUG _ Topband Reflector
Re: Topband: Dual band shunt-feeding tower on 160/80
I've done exactly what Herb suggested: hung a sloper for 80M off the side of my 160M shunt-fed tower. Neither antenna knows the other is there and both work pretty well - meaning I'm satisfied with what I get out of them. Interesting. I have tried verticals, slopers, inverted V's and other 80 meter antennas on or near my 160 meter tower with little success. The impedance of any such antenna seems to be severely altered by the nearby tower. I suspect it depends on the electrical length of the tower. Mine is close to an electrical half wave on 80 - 100 feet of Rohn 25 with a 7 element 6 meter yagi, approximately 30 foot boom sitting at 103 feet. At one point in time the 160 meter shunt feed could be made to provide an excellent match on 80 simply by changing the series capacitance. However, after I cut down several nearby trees that no longer works. 73, Paul N1BUG _ Topband Reflector
Re: Topband: Closed for the season or maybe just redecorating..
A couple weeks ago I declared my intention to be back on making some feeble noises in a few days. Unfortunately that hasn't happened. At this point I have no idea when I will be QRV, as I just don't have enough time or energy to get the station set up and repair finished. 73, Paul N1BUG _ Topband Reflector
Re: Topband: Lightning QRN season?
On 08/12/2013 11:29 PM, Mike Waters wrote: Frankly, I think many hams are just too lazy (maybe disinclined is a better word) to try and copy weak signals buried in the noise. To me, that's what's the most fun about this hobby. That's why I loved working 144.2 MHz, the challenge. And I managed to work 30 states there from a section of Toledo, Ohio that had prolific power line noise. I love a good brain-vs-noise challenge too. That's what attracted me to VHF/UHF EME back in the day when it was done with CW. That's probably why I DX on 160 and 6 meters today. Everything in between is just too easy! All I can think of is, what a bunch of wimps. Sorry if that offended anyone, but what else can we say? :-) I'm disappointed. I had planned to remain active all summer on 160 this year. I thought I had a light summer on tap. Instead, what was to be minor work on my home turned into an all summer battle with both exterior walls of the ham shack being torn out and rebuilt, among other things. I've been completely off the air for some three months now. 73, Paul N1BUG _ Topband Reflector
Re: Topband: 160
Sorry I'm missing all the fun! I recall being active on 160 throughout the summer back in my early days on the band, mid 1980s, and working a lot of DX during the summer. I had intended to be active all through the summer this year, especially to see what I could work fro the southern hemisphere. Life, however, had other plans. I've been off the air for a couple of months but hope to be back by late September if not sooner. I have been enjoying the threads about W6AM and W4BPD. 73, Paul N1BUG _ Topband Reflector
Re: Topband: RFI ferrites
Hi Dean, Did you search for the right part number? Mouser indicates 748 of the 2.4 31 mix toroids in stock at $6.94 each. That is where I get mine from. The Fair-Rite part number is 2631803802. 73, Paul N1BUG All good topband ops know how to put up a beverage at night. _ Topband Reflector
Re: Topband: Fw: Mike, VK6Hd.
Mike's passing is very sad news indeed. I had many contacts with Mike over the years, both on topband and elsewhere. Mike helped inspire me to become the topband DXer I am today. I had been chasing DX on topband briefly in the mid 1980s. I was relatively new to the hobby then, and lacked practical knowledge of topband. Having listened to other stations working Japan, VK6, and other far off places and never hearing so much as a whisper of the DX, I thought it beyond my reach. Surely that must be the exclusive privilege of super-stations or else I was just a little too far and had no propagation at all. Having left HF for several years to work EME on VHF, I returned in 2004 still hanging onto the belief that VK3 would likely be my best DX. Then one morning I heard and easily worked Mike in VK6! I was shocked, but an even bigger shock would come two weeks later when I worked him again - this time the other way around at my sunset. Subsequent email exchange with Mike revealed he was not using a super-station but instead had simple antennas such as mine. In the months that followed I worked Mike several more times on topband, including at least one contact well before my sunset and well after his sunrise (both of us in daylight). Clearly I had much to learn about topband - and it had more to offer than I had previously thought. I soon learned that working VK6, which is near my antipode, is very much easier than working, for example, southeast Asia. Nevertheless, the contacts with Mike and his email exchanges prompted me to learn more about topband and to fully appreciate it. Topband DXing has become one of the most exciting and rewarding facets of our hobby I have experienced. Thank you, Mike! Rest in peace, my friend. 73, Paul N1BUG All good topband ops know fine whiskey is a daylight beverage. _ Topband Reflector
Re: Topband: solar wind, auroral oval images, D-region bite-outs
On 01/23/2013 09:17 PM, k...@frontier.com wrote: I would think that there's a high correlation between the polarity of the IMF and the K/A indices, so this polarity may not tell us any more than the K/A indices. Absolutely there is a very strong correlation. I suppose it comes down to what one wants to know and how soon one wants to know it. A index is a 24 hour value so it will usually not show much increase until a disturbance has been going on for many hours, even a day. K index (measured at Earth) is a 3 hour value but still looking at the previous 3 hour period so there is a lag. Suppose a disturbance starts at UTC. It won't be reported in K index derived from Earth based magnetometers until 0300. It won't show up officially in the A index until the following day, though SWPC does estimate the daily A index starting at 1800 UTC if I recall correctly. There is, however, a K index model which attempts to forecast K index a few hours into the future using solar wind data as input: http://www.swpc.noaa.gov/wingkp/ Raw solar wind data is more of an early warning system. It will show what is coming some 30 to 60 minutes before any Earth based magnetometer, depending on solar wind speed. It also shows what is coming sooner than the Wing Kp model. For the average MF/HF DXer I suppose the Wing Kp or even the previous 3 hour data of measured K index at Earth is quite sufficient. For catching VHF auroral propagation it most definitely is not enough, and I suppose years of that have biased me toward monitoring the earliest information available - even if it is in a raw state and requires considerable experience to appreciate. I pretty much always have an eye on the ACE plot: http://www.swpc.noaa.gov/ace/MAG_SWEPAM_24h.html NOTE, however, that following solar proton flares, the ACE data can become severely corrupted and useless. This affects all downstream models that depend on it, such as the Wing Kp and the much beloved (by me :) OVATION models. 73 -- Paul Kelley, N1BUG RFI Committee chair, Piscataquis Amateur Radio Club http://www.k1pq.org _ Topband Reflector
Re: Topband: solarwind and 160 prop
Hi Wolf, I'm not sure if I understand your question. If you are looking for real time solar wind monitoring, you might start here: http://www.aurorasentry.com I have assembled a collection of solar, solar wind, and geomagnetic real time data, originally to forecast and track VHF and UHF radio reflection from aurora. The site needs updating. I haven't had time for it in a while. Of particular interest is the ACE MAG SWEPAM plot which you can find on the Solar Wind Dst portion of that site, or directly here: http://www.swpc.noaa.gov/ace/MAG_SWEPAM_24h.html The red Bz trace in the top panel is the north-south orientation of the interplanetary magnetic field. It couples most heavily with Earth's magnetic field (producing geomagnetic disturbance) when it is south oriented. Note that there are versions of this plot available for time spans of 2, 6, or 24 hours, 3 or 7 days. While on the subject, I never have liked, and still do not, the ever popular NOAA POES Auroral Activity plots: http://www.swpc.noaa.gov/pmap/index.html These have to me proven very unreliable for the intended purpose of correlating to VHF auroral propagation, but also do not track as well with intensity of real time auroral disturbances at MF and HF. Much better I think, but not yet adopted by hams, is OVATION Auroral Forecast: http://helios.swpc.noaa.gov/ovation/ or OVATION Prime Real-Time: http://www.ngdc.noaa.gov/stp/ovation_prime/ Unfortunately this one lacks a good map overlay and takes some practice to read it correctly. 73, Paul N1BUG On 01/23/2013 12:24 AM, Dr. Wolf Ostwald wrote: Now is the critical factor whether the polarity of the arriving solar wind, developing the interplanetary mag field , fits the earth mag field or not. becuase if it does, the influence is by far greater than without it. Question is, where do i find that info ?? -- Paul Kelley, N1BUG RFI Committee chair, Piscataquis Amateur Radio Club http://www.k1pq.org _ Topband Reflector
Re: Topband: Another take on power line noise hunting
Thanks for adding to the discussion Don. That reminds me I forgot a couple of important details so I'm replying on-list to add them. I hadn't thought about using a spectrum analyzer even though I'm well aware of the increasing high frequency component as you get closer to the source. The bloom sounds like an even quicker way to get very close to the source than the variable frequency method (assuming, perhaps, there aren't too many overlapping noise radiations from multiple sources). I forgot to add I have been using a UHF FM link to hear audio from my home receiver in the field. In early stages with multiple noise sources being heard at home and in the field I couldn't sort one from the others by ear. I could sort them pretty well at home where I had the scope and felt that having one in the field would have saved me countless hours of frustration. In later stages comparing by ear started to be useful, though with some of the steady noises it was difficult to know for sure if I had the right one. I also had (and still have) many sources in the field that I do not hear at home on any band. I'm leaving them alone. It's amazing that I have one not more than 500 feet several of my antennas. Loud on HF through 135 MHz as I pass by it, deafening on ultrasound, but not a whisper of it at home. I would agree most folks may not need the ultrasonic unit but I owe mine a huge debt of gratitude and will never be without one - preferably the most capable one I can get my hands on. It saved my bacon this summer. The power company had been out and wrote a work order to address multiple problems. Three months had passed and the work had supposedly been completed, yet I still had noise from all but one of those poles. Nothing I said about my RF observations was convincing him to come out and check again. He was doing everything possible to convince me I couldn't possibly have power line noise any more and whatever I was hearing must be generated in a home and radiated from power lines. I wouldn't have been the first to go down in flames dealing with this company. I was losing the argument big time until I asked him to kindly explain why I could be hearing ultrasound from a particular insulator and the changing sound pattern matched up perfectly with audio from the home receiver over the UHF link. He was back out here in 2 days, and 3 work days after that every one of those poles had been rendered absolutely silent. 73, Paul On 01/05/2013 02:41 PM, Don Moman VE6JY wrote: Similar observations here Paul in my never ending battle to keep on top of the noise situation in my rural area - mainly 14.4 kv distribution and some 25kv 3 phase stuff. Many sources top out above 135 mhz but well below 450 so a yagi in between is certainly helpful. Like a ch 13 tv yagi or something for UHF mil aircraft. In the vehicle I often like to use an old (i.e. analogue and inexpensive) spectrum analyser like some of the portable Texscan CATV ones. Mine is the VSM-1 which covers up to 300 mhz so that coupled to a little whip on the vehicle is almost always enough to get you to the nearest pole or two as you drive by. The AVCOM PSA 65 I have is also OK but one wants something with a really wide RBW so you gather lots of the noise energy and in my experience the cheap and dirty Texscan gives me the best noise bloom as you drive by the pole. Depending on ambient light it can be tough to see the screen and still drive safely so fortunately they also have a wide band video out jack that can be used to drive a amp'd speaker. To zero in a bit closer I use the ICOM R-10 and a Create 50-1300 mhz log with the rear elements removed to make easier to get in the vehicle. It's OK but the pattern is not as nice as a single band yagi. But with this setup I can almost always tell the utility which pole is the culprit and they take it from there. I have some ultrasonic stuff and the power guy has the Radar Engineers unit - the hand held dish style and these are generally NOT helpful in finding much other than in maybe 1/3 of the cases confirming the findings that we are on the right pole. I think on many of the sources the arc is weak enough that there's not much ultrasonic energy. I have seen it not work enough that I wouldn't spend much energy or money on this route. The one ultrasonic device you want the power guys to have is the hot line sniffer from RE and that can (in their hands, not yours) pinpoint the exact hardware. The most challenging noise situation that I have experienced is the faulty transformer (all from brand new units) with a micro arc inside the can. TONS of LF noise around 80 and 160m but nothing at VHF, nothing ultrasonic as everything is in the can. And as you know, the noise at lower frequencies can travel a LONG way and you'll get noise peaks at corner structures etc, all trying to mislead you. When you don't see any obvious source in the normal fashion and there's still
Topband: Another take on power line noise hunting
I've been following this discussion with interest. I spent the summer tracking down more than 20 sources of power line noise. As an offshoot of that I've made it my mission to help clean up RFI in my little corner of the world. I've been slowly drifting away from DXing and this has turned out to be my new area of interest. Since this topic is perhaps of interest to topbanders, and since my experiences seem to vary somewhat from the typical reported here so far, I thought I would take a moment to share some observations. I should probably note I was dealing with a mix of 13.2 kV distribution lines and 46 kV transmission lines. My hunt was made more challenging by the fact I had multiple sources in a relatively small area and could often hear more than one at a time even with directional antennas and attenuation. My tools this summer were 135 MHz AM receiver with 3 element yagi and step attenuator; LF/MF/HF/VHF/UHF AM receiver with DF loops for low bands and 7 element yagi for 445 MHz; ultrasonic receiver with dish. Low frequencies, eg. AM BC or 160 meters were *occasionally* useful in locating a general source area. Sometimes the area identified turned out to be an area of *radiation* but the noise was *generated* elsewhere. Often the relatively close proximity of multiple sources made low frequency tracking useless. VHF was always useful in finding a source area, 80% of the time resolving it to a single pole. The sharp, deep null at exactly 90 degrees off axis of the yagi proved very useful for confirming a source structure. Poor resolution/accuracy of signal strength metering was perceived as a problem. UHF was very helpful in a few areas where the noise was particularly strong at VHF and/or signal strength so close over a span of several poles that VHF could not pick the source pole with high confidence. So far, experience indicates this is more likely to happen on the transmission lines. They're a bear. Again, poor or no signal strength metering (signal below AGC threshold) was perceived as a problem. The first ultrasonic unit tried was a waste, finding something at only 10% of RF noisy poles. The second unit was able to hear something from about 60% of the same 21 poles. The figures are averages over more than 10 runs with each unit. The two were also tested on a spark signal range under somewhat controlled conditions. These things are definitely not created equal! To date I have identified and had the power company fix almost everything I have worked on. The remaining open case involves a short section of a 46 kV transmission line which is extremely perplexing due to the specific nature of the issue (details on request). Just when I starting thinking I was getting good at this, I came up against this one. If I were doing this strictly for myself these tools would be more than adequate. Since I'm not and I only have so many hours in a day I have several upgrades on my wish list: HF/VHF/UHF AM receiver with wider bandwidth better signal strength metering Log periodic dipole array covering ~100 to ~900 MHz for frequency agility while maintaining some directional properties Portable oscilloscope for observing noise signatures in the field (I'm hoping it helps sort out overlapping source radiations) Yet another upgrade of the ultrasonic unit. Comments are welcome, even if it's to tell me I'm clueless! :) 73 -- Paul Kelley, N1BUG RFI Committee chair, Piscataquis Amateur Radio Club http://www.k1pq.org ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: Subject: Re: Why the DX doesn't always work split? Especially on the low bands
On 12/22/2012 08:18 PM, Steve Ireland wrote: On the 16 December, there was a nice opening into the eastern USA with signals to S6, but the static and general atmospheric noise was about the same level - a common phenomenon. As it is summer in the southern half of the world, it is REALLY noisy! I ended up asking for heaps of repeats mainly because of the noise. Perhaps a comment from the other side of that same opening? I called Steve a few times that morning but stopped because even with a 200 Hz filter and audio peaking it was difficult to hear when he came back to people through the callers. They were spread out some but it only takes a couple who call too long or with questionable/unfortunate timing to make things difficult when the DX is S7 and the callers are 20 to 30 over S9. Steve had a relatively small pile (10 callers at a time?) of reasonably well behaved DXers. For me it was marginally OK working simplex but I very likely might have missed it once or twice had he come back to me. I heard Steve answer a few stations who did not copy him right away due to the other callers (I'm assuming, because there were others still calling and they subsequently seemed to hear him just fine when in the clear). That may have slowed his potential QSO rate somewhat but not drastically. With a few more callers or a couple who are particularly eager it can easily go from that to total chaos. Of course there are times when there isn't enough space on the band for all DX with multiple callers to go split. 73, Paul N1BUG ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: PE coated RG6
No problem at all here, using two or three types of compression F connectors. PE jacket flooded direct burial RG6 type cable, one foil and braid, NOT quad shield. They have been in service now for 4 years with no issues. Best part is my local squirrels don't seem to like the taste of polyethylene. 73, Paul On 12/14/2012 10:20 AM, Craig Clark wrote: Anyone have any success installing compression F connectors on polyethylene coated RG6? I am having no luck with either double or quad shield compression or older crimp F connectors. ___ Topband reflector - topband@contesting.com
Re: Topband: detuning shunt fed tower
Thanks to everyone who replied (many off list)! I will be working through personal replies and follow-ups but have spent most of the last 24 hours frantically investigating my station setup. I do have some SEVERE new noise issues, and that vertical still needs to be detuned. However... I also found connector problems in my receive system, which I am trying to correct as best I can. I became highly suspicious yesterday when I bumped the desk and my noise on a particular Beverage/frequency went from S1 to S8! The culprit in that case turned out to be a blasted RCA connector which has now been ripped out, thrown in the trash, and replaced by an SO-239. A similar fate is about to befall a few more of the devils! Thanks 73, Paul N1BUG ___ Topband reflector - topband@contesting.com
Topband: detuning shunt fed tower
I have made numerous attempts to detune my vertical over the past 6 years. I admit at this point I have no idea what I did wrong or what to try next. I have what I believe to be evidence the vertical is interacting significantly with the several Beverages, which of necessity are close to it. I attempted to follow the advice in Low Band DXing and on W8JI's outstanding web site but I didn't get very far. The vertical is 100 feet of Rohn 25 tower with a ~30 foot long 7 element 6 meter beam sitting at 103 feet. There are approximately 100 on-ground radials ranging from 60 to 200 feet in length. It is gamma matched by a 4.5 inch triangle of #6 wires spaced approximately 30 inches off one side of the tower. The short is at about 32 feet (from memory, may be off a couple of feet in either direction), BUT the 3 wire gamma rod continues to approximately the 60 foot level. Is this a problem? Should I get rid of the excess length of the gamma match? Previous attempts to detune the vertical ended in frustration. First I attempted to use the gamma match as the loop since that would be very convenient. Using an MFJ-259B I was able to get the loop down to about 2 ohms. This occurred with about ~900 pf capacitance vs the few thousand pf I was expecting. It did not seem to have any noticeable affect on what I presume to be vertical / Beverage interaction. I tried the same thing with a similar sized loop placed half way up the vertical on the side opposite the gamma match, with similar results. Perhaps I am wrong about the nature of the problem? Local noises (eg. plasma TV) don't change by the expected amount (F/B of Beverages) when I switch among Beverages. Often, while listening to such a noise on one Beverage, switching from the vertical to a different transmit antenna (thus leaving the ~250 feet of coax feeding the vertical open at the shack end), there will be a dramatic change in noise on the Beverage, depending on the particular noise and Beverage selected. I take this as evidence the vertical is re-radiating noise and that detuning it should help. Is that a valid assumption? Is there any other method I can use to detune the vertical? How about listening to a signal coming from the back of a Beverage and tuning the vertical decoupling section for minimum signal on the Beverage? Would that be valid? Any other ideas? Noise is getting out of hand around here. Every time I listen there seems to be a new one. Of course I will continue to track them down and attempt to mitigate at the source. But the need to get my station receive performance as good as it can be has never been more evident. 73, Paul N1BUG ___ Topband reflector - topband@contesting.com
Re: Topband: Remote SDR Receive only setup
On 11/27/2012 12:35 PM, MIKE DURKIN wrote: Not there anymore Yes it is. RX array-Demo audio file .mp3 The above, though perhaps somewhat confusing, actually links to 2 different things. Click on the part of it that says RX array and you'll get the power point presentation. Click on the Demo audio file .mp3 portion and you'll get the audio file. Paul ___ Topband reflector - topband@contesting.com
Re: Topband: Vertical Array Over Uneven Ground
I suspect most Americans are more comfortable with our own measuring system plus our ham bands where antenna formulas are still published in feet and inches. I suspect most (or at least many) Americans are resistant to change and unwilling to give anything different than what they are used to a fair try before dismissing it. When I don't have to deal too extensively with materials made to specific sizes for the U.S. market, I do much of my measuring and work using the metric system. Why? Because once I got used to it, I find it much easier to work with. My notes on projects going back over 20 years usually give dimensions in metric (eg. plate line dimensions for a VHF amplifier in millimeters). I have grown somewhat weary of converting to another system just so that other Americans won't grumble about my choice of units. I may stop that practice. If other Americans don't understand the measurements and can't be bothered to do the conversion, they probably don't really want/need the information. Paul ___ Topband reflector - topband@contesting.com
Re: Topband: Tuning 160M Dipole
On 10/30/2012 07:56 PM, Bob K6UJ wrote: I believe with frequency changes of 10KHZ the wire length changes by about one foot. So if it is resonant at 1.800 and you trim off one foot it will be resonant at 1.810. If you can find the resonant freq (where the lowest SWR is) then you can see how far you have to move. Usually I use an MFJ antenna analyzer to see what the frequency of lowest SWR is, then calculate how much to shorten (or lengthen) each end of the antenna: (234/current frequency) minus (234/desired frequency). That had worked well until I started putting up several antennas in close proximity to each other. With the current crop of antennas that method proved nearly useless, since the frequency of minimum SWR did not move by the expected amount. My somewhat uneducated assumption is that when the antenna is significantly interacting with something in its environment, all bets are off. 73, Paul N1BUG ___ Topband reflector - topband@contesting.com
Re: Topband: Fishing beacons redux
An observation: There seem to be more LOUD buoys this season than ever in the past. I wasn't on much last season due to local noise but it seemed to me activity on topband was WAY down from the past several years, perhaps due to people going back to higher bands. Could the two be related? Less amateur QRM makes 160 a more attractive place for buoys? Just wondering... 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: W5UN this morning (Tuesday 25th September) - long path into EI?
On 09/25/2012 03:12 PM, Cormac Gebruers wrote: Hi, I was up early this morning (Tuesday 25th September) and heard W5UN come up on 160m at 0444utc. Though very weak and with deep QSB, he was by far and away the strongest on my K9AY when switched NE and next strongest when switched SE. I'm in IO51, he is in EM19; direct bearing is 296 degrees (WNW), long path is 116 degrees (SSE). Was he really long path (33428km) or is some other propagation mechanism at play here? Hi Cormac, I have four reversible Beverages giving directions every 45 degrees around the compass starting at due north 0 degrees. It is not uncommon to experience DX stations coming in at wildly different headings from direct path, even 180 degrees off. Often when this happens, the signal will be there on more than one Beverage, sometimes all of them! In almost all cases, switching to a low dipole has resulted in good reception, sometimes better than any of the Beverages. I suspect the phenomenon is caused by signals arriving at a high vertical angle, where directivity of the Beverages is questionable or non-existent. I have no experience with K9AY loops. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: The use of digital modes on 160 metres
On 09/19/2012 08:33 AM, Tom W8JI wrote: Maybe we will need two versions of 160m DXCC - one of which specifically states SSB and CW only or somesuch! That's a good suggestion. It really should be one award for the case where a human operator copies the signal, a man and his radio, and another certificate where a machine actually copies the signal, a man reading the text decoded and printed on a machine. This fits with the trend to make rewards in life increasingly less dependent on human effort, patience, and skill, and those who prefer to do it with human involvement. There should be two clear classes. Awards fairness is the primary issue for me and it is the reason I came back to 160/HF after many years chasing DX on VHF/UHF EME. After digital modes largely took over that world, those of us who were stalwart CW (and/or SSB) operators argued for mode-specific awards. That would have made the difference between staying or going for some of us. But ARRL was strongly opposed, as were most digital operators who insisted on leaving things as they are. Most were vehemently opposed to mode-specific awards. It obviously was and remains a lost battle. At least on HF we have CW *or* SSB awards, which is a huge step above the free-for-all we are forced to endure on VHF and up. But even here, I think adding a mixed non-digital category (for SSB and CW) would be a step forward in today's world. It would undoubtedly improve my somewhat waning enthusiasm for the hobby. For the record, I have tried JT65 and other digital modes. I'm not opposed to them, but they are not for me. To each their own, of course, but I would rather watch paint dry than work digital modes. For me it takes the fun and sense of personal achievement out of operating. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Soldering in the wild!
I use a soldering iron tip with a regular propane torch. The tip attaches to just about any torch with a setscrew. Slip it over the end of the torch, tighten setscrew. I haven't looked for them recently. I bought this at a local hardware store 30 years ago for about $2 I think. It gets hot enough to solder #12 copperweld at 100 feet above ground with an air temperature of zero and moderate breeze. I could have been content never having acquired that particular bit of knowledge. ;-) 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Beverage strain auto-disconnects
On 07/24/2012 08:14 PM, KAZeringue wrote: @N1BUG. The WD1A is fairly tough, ~200lbs break strength. Tie it to the supports/trees/insulators/whatevah with a single strand of 20-25lb test monofiliment fishing line. Tree falls on WD1A, maybe you then need only replace monofiliment fishing line supports to re hang the wire instead of splicing/weatherproofing. Thanks W4KAZ and everyone else who has offered suggestions. I've been using a similar method, using #18 soft copper wire to attach the Beverage end insulator to the support. It is attaching the Beverage wires to the transformer box that is the bigger problem. There are two basic approaches: 1. Solidly attach the Beverage wires to the box, then attach the box to the support with a breakable line of some sort. This has the disadvantage of leaving the coax, ground wire, box, and the Beverage wire subject to strain and possible damage when something falls on the Beverage. Leaving extra length in the coax and ground wire is no guarantee, as I've seen boxes snag up on/in the next tree after breaking loose from the end support. 2. Solidly attach the Beverage box to the support, then attach the Beverage to the support *and to the box* with something that breaks or disconnects when the Beverage is under abnormal strain. I've been using the #18 copper wire to attach the Beverage to the support, and 1/4 blade connectors to attach the Beverage wires to the box. The Beverage falls without breaking, while the box, coax, and ground wire stay with the end support (tree in my case). This has worked very well, but the blade connectors get black and ugly after a year or so out in the weather. Whether this causes any real problem has yet to be determined. The two suggestions I'm looking at are: A. Coat the blade connectors with automotive silicone grease. B. Use banana plugs on the end of the Beverage wires with jacks in the boxes. My supports along the run (everything that isn't an end support) consist of 2x2x4 pieces of pressure treated wood, oriented vertically and nailed to the side of the support tree. I drill loose fitting holes about 3/4 from the top and bottom for the nails. I use galvanized nails longer than needed, driving them into the tree far enough to hold firmly but leaving the wood block an inch or two away from the tree. This allows the tree room to grow several years before it starts to surround the insulator. The WD1A wire passes through a 1/4 hole in the center of the wood block. Obviously these support blocks aren't really insulators but as far as I can tell they cause no problems. The slippery wire slides through the block easily when something falls on a Beverage. Of course, the same basic technique could be used with some material that actually is an insulator. ;-) 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Connector installation on flooded cable
On 07/21/2012 09:55 PM, Bill Wichers wrote: If you're in an area where DSL service is available try asking the foreman at your phone company's local service yard. Rural C wire is not a twisted pair so it is generally replaced when a customer orders newer service that uses higher frequencies than the POTS that the rural C wire was intended to support. Wow! I always enjoy these bits of news from the rest of the world. Around here, rural C wire is never replaced. If a new DSL customer has problems, they will run a test on the line and try to solve it by re-doing connections, etc. If that doesn't fix the problem it's We're sorry, but your phone line is not of sufficient quality to support DSL. I'm afraid we cannot offer you DSL service. Have a nice day. I'm not saying the rural C wire drops are responsible for DSL failures, only that a lot of folks who theoretically should be able to get DSL can't, and replacing wire is not a strategy considered. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: Connector installation on flooded cable
I am replacing the coax in my Beverage system and have a dumb question. When using flooded cable and compression F connectors, is it necessary to clean the goo off the stripped cable prior to installing the connector? If so, how? 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: Beverage strain auto-disconnects
Another question. My Beverages run through forest. Falling trees caused many wire breaks and high maintenance until I started using strain disconnects at all ends. I use a fuse link of #18 soft copper wire between the end insulator and the support pole/tree. For the Beverage connection to the transformer, termination, or reflection transformer (most are WD1A reversible type), I've been using 1/4 blade connectors. This allows the Beverage to fall and simply unplug itself from the boxes. In 4 years using this system I have not had to splice a single wire, and they have been down MANY times. My concern is those blade connectors, which turn an ugly mottled black within a year after installation. I'm not sure if this is a real problem or an imagined one. The Beverages still work but I'm concerned about possible BCI or other crud being generated in these connections. Does anyone have a better idea for disconnects to protect Beverage wire and boxes from destruction? I could replace these connectors every year or two but that would be lot of work. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Connector installation on flooded cable
Thanks guys. All replies were helpful. I now have the information I need on this. I'm happy to know I can leave the goo alone. Now, as soon as I get enough weeds and thorny bushes out of the way to pull up the old coax and run the new stuff... 73, Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Beverage strain auto-disconnects
On 07/20/2012 11:09 AM, Jim Brown wrote: I understand why Paul does what he does. If your Beverages run through rough terrain, as mine do, it can be a real challenge to walk the Beverage to check and repair it. And as I get older it gets tougher. :) Mine run through very rough, uneven, steep, overgrown terrain with plenty of swampy muck in places. I can diagnose most end disconnections from the shack by looking to see which directions are not working. Of course I still have to venture out with saw to remove whatever has fallen on the Beverage before I can pull it back up. But with self-disconnects at the ends, at least I don't have to wander around with a bunch of tools for splicing wire. Even so, if I had single wire Beverages I would probably just let them break and splice as necessary. However, single wire Beverages are out. The only way I can have Beverages in more than a couple of directions (south, southwest, and west) is to make them reversible. All feeds have to be on the end that is on high ground so that leaves two-wire Beverages with a reflection transformer at the far end. That established, I analyzed the possibilities. Two separate wires side by side would be a lot of work to put up and maintain since I cannot dig holes for posts and must use existing trees/bushes for support. I settled on WD1A wire for ease of installation. BUT the stuff is a nightmare when it breaks! It is never a clean break, but rather a badly frayed section at least several inches long. Over time the Beverages quickly shorten from cutting out the bad section and splicing, requiring re-adjustment of the end points and/or splicing a new section in. Splicing the stuff is not fun with the steel strands, and splices must be COMPLETELY waterproofed or else the steel strands rust through and the wire becomes too weak. Not to mention the tinned copper strands seem to get eaten by the rust. it didn't take many experiences splicing this stuff to realize I needed to come up with Plan B! I will admit I haven't tried window line. I should be able to install it with a level of aggravation somewhere between two separate wires and the WD1A I now have. But I imagine that stuff isn't the most fun to splice when it breaks either? It's amazing these Beverages work as well as they seem to, considering the terrain and compromises. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Fw: Deterring Critters was:Re: How Good is Good Enough?
But you want it insulated. Id suggest #18 Copperweld with a PVC lacket. A PITA to unravel and hold in place but should be up to the task. The stuff the telephone company uses for drops here is 2 x #18 copperweld with very thick insulation (not sure what material). It is made like zip cord and is easily separated into two single insulated conductors. It can sometimes be had for free if you look around. 25 years ago I used the stuff to make my first BOG. It was cut in several places by neighborhood kids, but when cleaning up my property and laying radials 2 years ago I pulled up the sections of it. There had been no critter damage over the years. Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Deterring Critters
On 03/13/2012 07:01 PM, Bill Wichers wrote: You can get coax with a PE outer jacket, although I think they usually use MDPE instead of HDPE for coax. All you need to do is order the direct-bury type, which should almost always have a PE jacket. Getting the flooded kind will also help if you do get any tooth-holes in your cable. Yes, and it seems to deter them. I was using regular PVC RG-59 cable for Beverage feeds for a while. It was constantly getting munched by critters. Since switching to RG-6 with a PE jacket three years ago (it also happens to be flooded) I have yet to find so much as a single tooth mark. It doesn't hold up to a chain saw very well though, and neither does LDF5-50A or 0.84 CATV cable! ;-) Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Fw: Deterring Critters was:Re: How Good is Good Enough?
On 03/13/2012 03:26 PM, Bill Wichers wrote: That material that looks like superman's zip cord is known as Rural C drop wire. Thanks for the information on this. It is virtually indestructible stuff. At one time I was interested in buying some, but couldn't locate a source. I like the description superman's zip cord ! Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: How Good is Good Enough?
If you need a preamp on any Beverage you have a problem IMO. Its too long, poorly terminated or there is a lot of feedline loss. Or you've been forced into some other bad situation. I have a local noise problem that is beyond my control. Unfortunately I can't afford the DXE noise canceller so I got an MFJ. With my ~600 foot Beverages as main antenna and a very short vertical as the aux antenna it will completely null the noise (on most Beverages). Unfortunately with its high noise floor I lose several dB S/N unless I use a preamp ahead of it. My Beverages have lower signal output than most in some directions, since they are reversible using WD-1A wire (lossy as a transmission line). Not everyone can construct an ideal station, but even with all these problems it is far better than not having Beverages at all. The bottom line is using a preamp buys me several dB S/N I cannot get any other way (only when using the noise canceller). Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: 3C6A
On 02/24/2012 01:46 PM, Jim Brown wrote: Actually, what we need is a long time commitment to 160, with an experienced operator, high power, and a decent RX antenna pointed WNW. Agreed! Which prompts me to ask, what is it about 3C / 3C0 that I don't know? Are there exclusive travel restrictions? I am wondering why there hasn't been a major DXpedition or a topband focused op from either entity (in my time on the band). Both seem sufficiently rare to warrant more attention. Just curious and trying to learn something. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: LOTW Participation
It's easy enough to upload logs and take care of the Ham on the other end who may not use real QSLs. Thank you Julius. I am known as a dinosaur to my friends. I do not readily adopt new technologies and ways of doing things. But LoTW is my salvation, lest I leave the hobby altogether. I upload 100% of QSOs to LoTW, whether I need a confirmation or not. It may help the other guy! I wish more people would at least upload to LoTW to help me. I would *very* much like to have paper QSLs for all the DXCC entities I have worked on 160, but that isn't going to happen. I finally realized too many people were paying the cost for my efforts to try to keep up with the paperwork. As a result, I depend on LoTW for confirmations now. When I work a new one all I can do is hope my QSO partner will upload. To cut down incoming requests I no longer call CQ or run stations. Generally I will only call stations who are flagged by my spotting and logging software as LoTW users or whom I strongly suspect will not be needing a paper QSL from me. In a contest I only do SP, skipping stations who are not flagged as LoTW users. I'm sorry, but that is how it needs to be. I know of others who do the same, albeit for different reasons. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Unintentional QRM on TB
I listened to HK0NA this morning around 1.8328 and he was sending 12 after his CQ. and folks were madly calling 12 Khz up, and 12 Khz down from his frequency. While it may not be an every day thing, this is common enough on topband so that anyone seriously attempting to work DX there should be familiar with what is meant. 12 is short for QSX 12 which is short for QSX 1812. Time is of the essence on a DXpedition so abbreviations are used wherever possible. If the operator meant up 12 or down 12 he would send UP 12 or DWN 12 (or DN 12). 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: BCI chase update
On 01/08/2012 04:46 PM, Lee K7TJR wrote: Paul you might want to be careful just shorting the receiver input. This would also put a short on the output of your preamp. This would have the preamp blasted with RF from your TX while trying to feed a short. My guess would be you could destroy preamps doing this. Clarification: Actually what I had in mind was to place the short at the input of the preamp. I want the preamp protected too. My only concern is the preamp might want to oscillate with a short on its input. I don't know whether these low frequency, medium gain preamps are prone to that or whether it would harm anything if they did oscillate. The 25+ dB gain, very low noise figure VHF/UHF preamps I am more used to can get pretty squirrelly with something other than 50 ohms on the input. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: BCI chase update
Prompted by Roger, N1RJ, I decided to do some digging around. Aided by isolating specific stages of my receive signal path as much as possible, and using precision 3 and 6 dB pads at various points to see where they dropped the IMD more than the attenuation of the pad(s), I have come up with a list of suspects. 1) The preamp. This was oversight on my part. A review of the original construction article clearly states a filter will likely be required if using a Beverage. Evidence: I simplified the signal path to BeveragePreampReceiver. Placing a 6 dB pad before the preamp dropped the IMD level more than 12 dB (may be closer to 18, I did not attempt to verify). Placing the 6 dB pad after the preamp dropped the IMD products 6 dB. 2) The ICE 196 receiver protector. Evidence: 6 dB pad before the 196 reduced IMD more than 12 dB. Placing the pad after the 196 reduced IMD 6 dB. Bypassing the 196 reduced IMD more than 12 dB. 3) A relay used to switch the preamp in and out. This relay had apparently failed, since replacing it with another of the same type made a big difference. This likely explains why my IMD problem when using the preamp went from annoying to severe a couple years ago. (I am aware relays in a receive signal path can be problematic due to insufficient current to clean the contacts). Based on results of this investigation my proposed plan (once I figure out how to fund it) is: 1) Replace the preamp. I'm not in the mood to build another one from scratch so I'm leaning heavily toward the Clifton Labs Z10040B. 2) Use a HPF in front of the preamp. Whether actually necessary or not it seems like good practice. I am leaning toward the Clifton Labs Z10022A, although I am torn between that and the Par Electronics BCST-HPF. The latter has more attenuation at the high end of the BC band, but not as much at the middle and low end. 3) Get rid of the ICE 196. I've had it with these things. This is not the first problem I have had with these devices generating crud. I have not as yet come up with a plan I am entirely comfortable with for receiver protection in its absence but I am leaning toward using a relay to short the receive signal path to ground when transmitting. Rather than put an additional relay contact in series with the signal path, I am thinking about having a normally open contact connected to the signal path, taking it to ground when transmitting. I welcome any comments. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: BC filter follow-up
Thanks to everyone who sent suggestions on my problem. Those who did not receive a personal thank-you note is because mail to you bounced. I thought it might be helpful to post a follow-up with links. In no particular order: http://www.arraysolutions.com/Products/BCB%20RF%20Filters.htm http://www.n1nc.org/Filters/160meter/ http://www.cliftonlaboratories.com/z10020_am_medium_wave_band_reject_filter.htm http://www.dlwc.com/ http://www.rescueelectronics.com/RF_Filters.html (note: may be able to custom build HPF) http://www.parelectronics.com/bcst-hpf-specs.php http://www.universal-radio.com/catalog/filters/4426.html http://www.morganmfg.us/radio-products/bcb-interference-filters/ http://yu1lm.qrpradio.com/bp%20yu1lm.htm http://www.cliftonlaboratories.com/z10022a_high_pass_filter.htm http://www.ac0c.com/main/page_antennas__homebrew_clifton_labs_z10022a.html ... Final comments on my specific issue: The overwhelming consensus is I should not be having anywhere near this magnitude of problem with skywave signals. I agree! But I have been chasing this on and off for years and have been unable to identify a specific problem with my station. I don't know what else to do but throw money at the problem and hope to cover up the symptoms of what surely is an equipment malfunction. I have ruled out building. I build a lot of stuff, but filters would seem to require test equipment I do not have access to. Flying blind is usually a good way to crash. :-) I am guessing my primary problem is mixing of signals in the mid to low part of the BC band, and will most likely opt for the filter with the best attenuation at those frequencies. I do not seem to hear anything particularly strong at the upper end of the BC band anyway. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Noise problem question
On 12/19/2011 04:41 PM, Joe Giacobello, K2XX wrote: It's more or less centered on 1836 and is quite wobbly and varies in amplitude and frequency. It's about 2.5 KHz wide, and it doesn't vary in strength when I change directions on the RX array. I'll have to check for a badnik somewhere in the house. When I got back on topband in 2002 I discovered the band had been invaded by what might best be described as unstable growls, each about 3 kHz wide, between 1810 and 1820. There used to be several, then last year there was just one. This season there is just one, but it seems consistently higher in frequency than the one I had last year. These things drift around a bit. There is very little change in strength when I switch receiving directions. The noise seems to come from everywhere, perhaps radiating from many points. I discovered I can also hear them at the club station, 2 miles away. A few years ago I suddenly had a much stronger one show up. It turned out to be a bad computer power supply in my own home. That one did vary in strength as I switched antennas, strongest when on the Beverage pointed toward my house. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: QSL or CFM or R?
Fine. But in marginal conditions a single R can easily get lost to a static burst or signal flutter/rapid QSB. I still contend that RRR is the same length as QSL or CFM and more likely to be understood if part of it happens to be missed. Paul On 12/13/2011 11:13 AM, Doug Renwick wrote: Hold on just a minute. I am talking about a single QSL or single CFM not a long string of these. I don't need a long string of s. Besides the string or Rs wastes too much time. And also I am talking about marginal copying conditions. If the station is 60 over 9, then nothing needs to be said to confirm. Doug ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: My take on ARRL 160
I've decided to put my oar in the water regarding the comments on ARRL 160. I didn't operate this year but it is my favorite 160 contest and the only one I would seriously enter. Why? Because mostly it does end up being a domestic contest and I have some chance of being competitive with my modest station and limited real estate. There is no way on Earth I could ever be competitive in the DX contests but I can in ARRL 160. I do understand about it being unfair to the rest of the world and especially U.S. territories. In addition I am increasingly of the opinion having so many contests is unfair to a great many people. I love a good contest, but I don't think we need one nearly every weekend during the topband season in the northern hemisphere. As for not being heard... here in the northeast, QRM is INCREDIBLE in ARRL 160. It is a very popular contest and let's face it, there just isn't enough useful spectrum. Even people who normally hear very well may be challenged in this one. We cannot pause for more than a couple seconds between CQs or some big gun will try to take over our run frequency and refuse to move. Callers need to be quick. I cannot emphasize enough the importance of getting on frequency. Make sure you can zero beat and get EXACTLY on frequency of the station you are calling. It is amazing to me how many people cannot seem to do that. I always have callers 200 and even 300 Hz high and low, and then they wonder why I don't hear them. I don't hear them because 200 to 300 Hz away is someone else's run frequency and I am forced to use a 200 Hz filter with very steep skirts. That is how crowded the band is during this contest. It does no good for me to tune for off frequency callers. A distant caller who is S5 but insists on calling under another running station who is S9+20 or more is not likely to be heard. At least not by me! Those are my comments. I'll go back to being silent now. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: ARRL 160 conditions
Bang on zero beat IS a problem. I am noticing more and more of that as (Iguess) more and more guys rely on SPOTTING SOFTWARE! Agh! It doesn't make any sense to call exactly zero beat. Huh? As I stated earlier, out here with the QRM and crowding if you are not darn close to zero beat you risk not being heard. There is no point in calling if you are going to be under the big gun on either side of the station you wish to work. If you are referring to possible problems with two or more calling the same station and zero beat with each other, it CAN be a problem IF both stations are near the same strength. Otherwise I find it no problem to pick the stronger one, work him, then go after the other(s). It is much faster and easier if all callers are zero beat or very close than if they are all over the place and under the adjacent QRM. 73, Paul ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: ICE 196 Receiver Protector
Excuse me if this has been asked. I was wondering if anyone on here has ever used or is currently using the ICE 196 Receiver Protector? What's your opinion? I have been using them for some time. I suspect they protect receivers OK. I did have to put a bandpass filter ahead of mine. On nights with very good propagation I found my noise floor would rise, sometimes by 40 dB or more! Investigation revealed this did not happen with the ICE 196 removed, and did not happen with a band pass filter in front of the ICE 196. It seems to be ionospheric propagated signals overloading the protector. I found some extremly strong MW BC and SW BC up around 5 to 6 MHz on the nights this was happening. This is with 500 to 600 foot Beverages. I do not have any nearby BC stations. 73, Paul N1BUG ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: Propagation from Maine this morning
Finally some remarkable propagation! I got up about an hour before sunrise this morning to see if there was any sign of T30RH on topband. Nothing, so I parked the receiver on 1826.5 and went back to bed. I did NOT turn the amp on, trying to conserve $$. A few minutes prior to sunrise I was startled by a loud CQ. Can't be, I thought. Then he signs T30RH up 2! So I flew out of bed, tripped over the cat, but managed to flip the amp switch to ON before hitting the floor. Three minutes is a very, very long time when you are listening to the DX call CQ and the amp isn't ready. I was still too sleepy to think of trying barefoot! Five or six relatively long CQs, no takers. Finally the amp was ready! I gave my call twice and a very easy 599/599 QSO resulted. Jacek really was 599 here! Amazing! Quickly looking around I found Dave, KH2/N2NL CQ'ing with no takers, so I waited a bit and then sent my call ONE time. Dave came back... another quick, easy QSO. Great ears, Dave! My new S9+ local noise (from a defective furnace next door) came up just seconds after the QSO with Dave. By the time it stopped, the sun was well up and BU2AQ was fading into noise. Rats! Might have had a chance at that 40th zone were it not for the noise! Following a cold night the three to four feet of snow was finally frozen enough to walk on for Beverage repair. They had been down since the ice storm a week ago, but fortunately none had been dragged away by flood waters as I feared. All are now up and ready for action again. The self-disconnects at the ends of the WD-1A wire reversible Beverages paid off yet again. They disconnect and drop, but don't break. 73 -- Paul, N1BUG Aurora Sentry: http://www.aurorasentry.com Piscataquis ARC: http://www.k1pq.org N1BUG: http://www.n1bug.com ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: ICE-196 has a catch-
Bryon PAUL Veal n0ah wrote: The ICE 196 is a very cool design.but if you are sending out voltage on your coax to control an antenna switch, relay, etc...it may adversely effect the controlled device’s ability to operate properly- The company I purchased this from did not inform me about this, but I think it is a good to know- I now use radio Dan’s front end protector and the KD9SV solid state front end protector for my rigs- I've been using an ICE 196 to safeguard my receiver for several years and want to share something else I discovered about this device. I suggest using a bandpass filter ahead of the ICE 196 may be appropriate for some. I was having a mystery noise problem. The noise had no special characteristics. It appeared to be a large increase in normal band noise. I was only hearing it in specific directions, mostly SW and W. I couldn't find the source of the noise. Eventually I realized I was only hearing it on nights with exceptionally good low band propagation. One night I discovered, quite by accident, that removing the ICE 196 made the noise disappear. I later discovered placing a 160 meter band pass filter ahead of the ICE 196 also made the noise disappear, but placing the band pass filter after the 196 did not. My only guess is that a combination of very strong MW and SW BC signals were enough to cause the diodes in the ICE 196 to conduct, generating noise. I would note that I have no local broadcast stations, so any strong signals I get are propagated via the ionosphere! I did find some very strong MW BC signals on nights when the noise was present, and some *unbelievably* strong SW BC up around 5-6 MHz (I can't find my notes on exact frequencies). I have been running with the 160m BPF and ICE 196 for several years without problems. When using the Beverages on higher bands I must bypass the filter, and in so doing I still have severe noise issues on nights with excellent propagation. I need to add filters for the other bands! BTW I do send out voltage on my receive coax to control remote devices, but the ICE 196 is installed between my receiver and voltage insertion point (control box for remote devices). 73 -- Paul, N1BUG Aurora Sentry: http://www.aurorasentry.com Piscataquis ARC: http://www.k1pq.org N1BUG: http://www.n1bug.com ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
