Author Topic: Interferenc Mode  (Read 2891 times)

0 Members and 1 Guest are viewing this topic.

Offline Knorrli

  • Member
  • *
  • Posts: 36
Interferenc Mode
« on: May 21, 2015, 12:24:17 PM »
I am in the process of tuning (fine tuning later) my station and had some interesting effects around Interference Mode.

I only run M-field detection with a 2 x 8 windings, 1000 mm frame antenna; amplification 5x4 or 4x4 both channels, threshold 120 mV (RED). I am facing intermittent interference problems that push my station into interference mode over long periods of time.

I was away last weekend (Friday to Monday afternoon). When checking via Blitzortung my station was in "Yes, no signal" mode for the whole time, showing the "Latest Signal"  as per around midnight Friday night. As soon as I started my laptop Monday afternoon everything worked fine.

Last two nights, when I checked my station with Blitzortung, same thing, my station was apparently in long-term interference mode starting around the time I turned off my Laptops.

My questions:

Is it possible that the turned off Laptops on the same network somehow make the controller "hang" itself in interference mode? When monitoring my system the controller goes in and out of interference mode by itself regularly.

Is there any way to track the times the station is working normally vs in Interference mode over an extended period (days) to find out if there are patterns in these interferences?

Thanks in advance for enlightenment 

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #1 on: May 23, 2015, 10:35:48 AM »
Best way is to put station in 'manual' with no filters switched... watch and determine your environment, and determine best settings... the laptop power supplies may be causing the interference signals... once you determine your 'baseline' you can proceed to mitigate the causes of your interference.... yes, the controller will cycle in and out of interference if it's running automatic mode...  see http://www.wxforum.net/index.php?topic=20439.0  good stuff in that thread....
 


Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interference Mode
« Reply #2 on: May 23, 2015, 10:46:16 AM »
...these thoughts:
While communicating with some operators, I developed a sense that some of us might be
confused when we speak of "interference" and "interference".... :D
We might be using "interference" as 'a disturber or noise that degrades communication or data, or a system's operation'.
But we might also simply be referring to "a system going into 'interference' ".

System RED (and BLUE will likely operate in a similar manner) will go into one of two types of "Interference Modes" from time to time.  "Burst" or "Normal"
The System is designed this way, generally,
1. Because nearby active cells produce so many signals, so rapidly, that they cannot normally be recognized separately... and matter of fact, one "paradigm" of the developers might be phrased as "detected signals <30km are generally useless to the network"  with the current design, anyway.
So when you go interference because of nearby storms.... accept it, let 'er ride, and let the network do its net work.  :D
2. Unless you have a perfect location, sporadic 'disturbers' such as an arcing power line, may produce conditional interference that swamps the controller similar to nearby cells, such are useless anyway.  But they're sporadic, and when they cease, you'll come out of interference.
3. Repeating, identical, signals that might be caused by someone standing nearby with walkie-talkie, burst of repeating  power line noise... weird stuff.

Now, while Interference Modes can be triggered by non-lightning signals,  it is based on the "number of signals sent" within certain time frames.
Except for the limited 'repetition and recurring' algorithms for "Burst Mode", it has no recognition of "types of signals" and doesn't care.
Interference mode can be activated due to signals on all channels, or one single channel, or a combination if you're running 5 channels including both H and E field.

It also is one 'controller parameter' that is monitored over time and varied by the server/controller! 
In other words, the server/controller can lower or raise those limits depending on what it sees from your station! 
You only have "indirect control' of this response: your operating mode, gains and thresholds, etc.
The 'basic' purpose is to avoid sending "too many signals" or "EM noise pulses" from your station.

These "interference parameters" operate no matter what mode you're in -Auto or Manual: 

If you look at your 'status' page when you access your controller web interface, down under "other parameters', you see something like this:
Interference Mode
•   Burst        When > 80sig/s in 3s average. Disable when 50% below threshold
•   Normal     When > 70sig/s in 60s average. Disable when 30% below threshold

...and if too many signals are actually sent under certain conditions,
that will 'back that down' to, for e.g. 30sig and 15sigs.... until
you can come out of interference, and the limits will rise again after some period of time.

So if over "some period of time" you've averaged over 70sigs/minute, you'll go into "Normal" interference, and stay there until it drops below 70sigs average.... which can be a long time... especially if the /controller has lowered the max limit temporarily for your controller to 15...! And if you are in Auto mode it could take even longer under certain conditions, as the controller may continuously cycle on and off and in and out of the mode.

For Burst mode... (short periods of repeating signals) it'll come out of interference much quicker.. a few seconds). It can be longer, again, if your limits have been temporarily lowered...

Remembering that you have only indirect control over 'Interference Mode" ... each channel's 'gain and threshold' settings.
If you're in "Automatic" mode, you have no access to your gains and threshold settings. Unless you desire to wait until the sources vanish on their own, you'll have to return to "Manual" mode, and reapply gain/thresholds settings under each specific amp, (the actual gains /thresholds have been set by "Auto", and they are NOT visible under the AMP settings... that shows you your settings so you must hit apply to reset the "Auto" parameter.
It follows, then, that if H channel A is the one causing the interference, you could back down channel A to 'just under noise trigger level, it will now come out of interference, and channel B  continues its merry way, and A now is of some use also.
You can take it from here.

(This is duplicated at http://sferics.us/bo1/index.php?topic=130.0 for cross searching )
« Last Edit: June 23, 2015, 06:29:13 AM by Cutty Sark Sailor »
 


Offline Knorrli

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #3 on: May 29, 2015, 07:40:48 PM »
Ok, so I changed to manual mode, grounded the Controller, selected an average amplification and the problem with Interference mode is gone.

However, compared to other stations in the vicinity (by Alberta standards), I consider my stroke count and Effectivity rate as disappointingly low. 

My network gear, Laptop and Controller get their power via a UPS. I created 3 scenarios and recorded ~ 1 min screenshots of my signal:
1. Standard configuration
              https://www.dropbox.com/s/ayibxz7twtijxok/AllOn_15-05-28_14-46.mp4?dl=0

2. Main breaker of the house off, Blitzortung gear (1 Laptop, Controller, Router, DSL) supplied by UPS
              https://www.dropbox.com/s/e58qheszjvq6dow/UPS_2015-05-28_14-52.mp4?dl=0

3. Main Breaker of the house back on, no UPS for Blitzortung gear.
              https://www.dropbox.com/s/1nksrqt12kjly4f/NoUPS_2015-05-28_15-23.mp4?dl=0

In addition I also have the Ratio graph for that period posted
              https://www.dropbox.com/s/vo6z8ccnbb6j48h/Ratios_2015-05-29.pdf?dl=0

There is a residential distribution power line about 30' away from my antenna (2x 1m loops) and I don't have too many options to place the antenna.

I am lost on how to improve the contribution of my station, any idea, hint on where to look for improving?

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #4 on: May 30, 2015, 06:29:00 AM »
Does your UPS have a USB power output, and are you connected to that?
Checked your signals on Sferics, and there was no B signal... just A, and the noise is all low freq components.
On your videos, it appears at quick glance that your 'noise' floor decreased by 50% on scenario 3.
Now, my system is also backed up with UPS, pure sine wave, and the http://www.powerstream.com/AC-1898.htm is connected to the UPS.

In my noisy environment, I could not eliminate much of the noise using big loops... ferrite core antennas dropped the junk by about 50%, since I could find a more suitable location easier, etc...
« Last Edit: May 30, 2015, 06:32:07 AM by Cutty Sark Sailor »
 


Offline dfroula

  • Forecaster
  • *****
  • Posts: 551
Re: Interferenc Mode
« Reply #5 on: May 30, 2015, 09:01:58 AM »

I only run M-field detection with a 2 x 8 windings, 1000 mm frame antenna; amplification 5x4 or 4x4 both channels, threshold 120 mV (RED). I am facing intermittent interference problems that push my station into interference mode over long periods of time.

Is there any way to track the times the station is working normally vs in Interference mode over an extended period (days) to find out if there are patterns in these interferences?


Your detected strike rate is extremely low. It is possible to set the graphs on lightningmaps.org for as little as 6 hours or as much as 4 days. Hover your mouse near the upper-right corner of one of the signal statistics graphs and a drop-down selection box should appear that allows a time-frame selection. This affects all of the graphs on the page, regardless on which graph the selection was made.

Could you provide some details of your antenna construction and connections to the amplifier? Sometimes an issue here can manifest as a low strike rates and detection ratios. I notice that your signal count varies wildly from near-zero to very high. I assume this is due to interference.

Also, I am only seeing signals from one of your channels this morning.

The noise in your posted videos appears to be related to the AC line frequency (harmonic distortion), as the signal on both channels varies at quite a low frequency. Do you have the system grounded per recommendations (single ground at the controller with SHIELDED CAT5 to the amplifier)?

Regards,

Don F.
WD9DMP

Offline miraculon

  • Sunrise Side Weather
  • Forecaster
  • *****
  • Posts: 4107
  • KE8DAF
    • Sunrise Side Weather in Rogers City MI USA
Re: Interferenc Mode
« Reply #6 on: May 30, 2015, 10:35:36 AM »
Since the locating ratio improved during the time that the entire house power was off, it seems to be a noise source inside the house.

Could you repeat with only the Main breaker on, and all other breakers "off"? Then start introducing one house circuit at a time.

If you could afford the time that the power is off (food in the fridge, etc), it might be interesting to watch the locating ratio as you introduce circuits back at your breaker panel. If you find the culprit circuit, then you can start looking at what is plugged into that circuit and start unplugging devices to see what makes the noise come and go.

Greg H.




Blitzortung Stations #706 and #1682
CoCoRaHS: MI-PI-1
CWOP: CW4114 and KE8DAF-13
WU: KMIROGER7
Amateur Radio Callsign: KE8DAF

Offline Knorrli

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #7 on: May 30, 2015, 11:49:27 AM »
Mike, Don, Greg, thanks for your replies.

When I checked, Sferic as well as my controller showed both channels working. So it must have been just temporarily. An interesting observation I made is that sometimes the two channels display a life of their own. Attached picture shows my antenna with the amplifier attached just underneath.

@ Mike: unfortunately, my UPS does not have a USB output.
Does the power supply you recommend come with the required USB connector?
 I was already thinking about your suggestion of going ferrite. There is not much room to move the antenna, since the room it is in might have to serve as an occasional guest room and I don’t think people would like to wake up with an antenna in their face.

@ Don: Yes, the controller is grounded as per recommendations and the network cables are supposed to be shielded CAT 5.
I feel like an idiot but I can’t find the hover point to change the time scale (http://www.lightningmaps.org/blitzortung/america/index.php?bo_page=statistics&bo_show=station&bo_sid=1342&bo_page=statistics&bo_show=station&bo_sid=1342). I assume you are talking about the top right corner of the Stroke Count, Signal Count or Ratios graph.

@ Greg: might have to make the time to just do that

Thanks again

Uli

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #8 on: May 30, 2015, 02:31:48 PM »
Mike, Don, Greg, thanks for your replies.

When I checked, Sferic as well as my controller showed both channels working. So it must have been just temporarily. An interesting observation I made is that sometimes the two channels display a life of their own. Attached picture shows my antenna with the amplifier attached just underneath.

@ Mike: unfortunately, my UPS does not have a USB output.
Does the power supply you recommend come with the required USB connector?
 I was already thinking about your suggestion of going ferrite. There is not much room to move the antenna, since the room it is in might have to serve as an occasional guest room and I don’t think people would like to wake up with an antenna in their face.

Uli

Actually I was going to suggest NOT using the USB output from the UPS...  No the little supply requires you to sacrifice a mini power cord from somewhere... and splice it in... make sure it's shielded, and carry the shielding over, if you go that route.. it's a good little supply.

Hang in there, you'll find it!
Mike
 


Offline Knorrli

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #9 on: May 30, 2015, 07:18:58 PM »
Mike, I am glad I don't have to source a 50 ft. USB cable.
Regarding ferrite antennas, did you source them in N. America, from Germany or did you build them yourself. If the latter where can one find some instructions (number of windings, distribution of windings, etc)

Thanks

Uli

Offline PaulMy

  • Forecaster
  • *****
  • Posts: 5509
    • KomokaWeather
Re: Interferenc Mode
« Reply #10 on: May 30, 2015, 08:21:10 PM »
Finally I can contribute  ;)  This may be what you are looking for http://www.wxforum.net/index.php?topic=19914.175

DonF is the expert on this!

Paul

Offline dfroula

  • Forecaster
  • *****
  • Posts: 551
Re: Interferenc Mode
« Reply #11 on: May 31, 2015, 10:29:55 AM »

When I checked, Sferic as well as my controller showed both channels working. So it must have been just temporarily. An interesting observation I made is that sometimes the two channels display a life of their own. Attached picture shows my antenna with the amplifier attached just underneath.


@ Don: Yes, the controller is grounded as per recommendations and the network cables are supposed to be shielded CAT 5.
I feel like an idiot but I can’t find the hover point to change the time scale (http://www.lightningmaps.org/blitzortung/america/index.php?bo_page=statistics&bo_show=station&bo_sid=1342&bo_page=statistics&bo_show=station&bo_sid=1342). I assume you are talking about the top right corner of the Stroke Count, Signal Count or Ratios graph.


One missing channel could be due to low gain and the 10% rule. If one of the channels exceeds the (default) 120mv signal threshold, it's data will be sent to the server. The other channel(s) will only be sent if their amplitude at the time of the trigger is at least 10% of the triggering channel's amplitude. This threshold can be changed on the settings page in the Tracker section, "Ignore Signals below Threshold". Best to leave at the default of 10%. This is to avoid sending waveform data on a channel detecting only the noise floor.

That hover point can be tough to find, as it is invisible. Some browsers do not seem to allow it, but Chrome does. Picture below.

I wondered if you had excessive length on the connections between your antenna loops and amp, but that is not a factor as the amp is essentially directly connected to your antenna, which is good.

I started out with loops with (I think) 54 turns on a 2 foot x 2 foot foam board former. Mine were shielded. Performance was good, with almost too much sensitivity. I had to back the gains down quite a bit. I eventually moved to my ferrite antenna design for ease in relocating the antennas to a noise free location. This is a major advantage of the ferrite designs! Performance is equal or better to my loops. There is some added delay due to hysteresis in the ferrite material, but the BO servers can easily compensate for that. That's why it's important to accurately specify antenna type on the blitzortung.org site.

I also noticed that the ferrites produced signals with sharper definition, with less rounded peaks. This is likely due to less capacitance in the ferrite designs. Sharper definition of the signals is a good thing!

See the ferrite construction thread in the sticky area of this board. Read the entire thread, as construction improvements were made along the way!

BTW, only the amp to controller CAT5 MUST be shielded. The network connection MAY be shielded, as long as you only have a single ground path to the controller. If the shielded network cable has a ground path through your router or Ethernet switch, it should be the only ground connection. If that ground is poor and you add another ground wire, the shielded network cable should be replaced with an unshielded cable to avoid ground loops.

Regards,

Don F.
WD9DMP

« Last Edit: May 31, 2015, 10:36:46 AM by dfroula »

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #12 on: May 31, 2015, 12:04:52 PM »
In order to process a signal, the current algorithm calls for the signal to be Twice the noise level, even if it exceeded your threshold level.  Even if a channel triggers at 100mv, if the noise level is 70, it doesn't meet the server limit of 2x Noise level, and will be dropped, prior to reaching the 'display' processing.  Even though you see it on your local display, Sferics, and the server, won't show it.  The server, currently, is using the 'best signal' from the station.  Now, the display on the websites show what's there after that 'initial' test, as far as I can determine, or been told, so any 'channel' that meets the "2x" rule will show, but that does not mean that specific channel was the one the server used to decide if it was a stroke, or not.  They experiment with that some, but that's the current algorithm unless Egon's changed it.  It will likely change from time to time.   Especially as they move into testing phase for system Blue... you may see some 'strange' things over the next month or two or three....
 


Offline dfroula

  • Forecaster
  • *****
  • Posts: 551
Re: Interferenc Mode
« Reply #13 on: May 31, 2015, 12:33:47 PM »
The 10% rule is enforced by the local controller and controls what is sent to the server for further processing.

Mike, it sounds as though the 2X noise floor rule is imposed by the server, not the controller? Even if done at the controller, I agree, it would prevent the servers from displaying the signal on the graphs.

Don
WD9DMP
« Last Edit: May 31, 2015, 12:46:49 PM by dfroula »

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #14 on: May 31, 2015, 07:36:22 PM »
The 10% rule is enforced by the local controller and controls what is sent to the server for further processing.

Mike, it sounds as though the 2X noise floor rule is imposed by the server, not the controller? Even if done at the controller, I agree, it would prevent the servers from displaying the signal on the graphs.

Don
WD9DMP
Yes, assuming he's still using that algorithm,.... the server determines everything.... generally, all we do is send signals, hopefully with the proper time stamp, the sharpest possible slope (fastest possible rise time) on the discharge pulse, standard phase shifts that the server expects for antenna type, and no diddled components that mess with filtering, tuning or delays or relative strength per gain / threshold and noise basement. At one point, last year, he raised that, I think, from about '1.5x' to two...I believe it was about the same time he lowered the trigger point to try to help with location accuracy, and improved the zero crossing toga the first time.  I think part of the issue is that 'distance' detection, while a good indicator of system overall quality, is not necessarily related to quality for the areas we're more concerned with generally... a system can respond well to the low frequencies of distance strokes, and really suck with the higher frequency components of nearer signals.  Responding more to local interference at low frequencies.... if you follow me. Richo and a couple of others think a lot of that has to do with antennas.... to a degree.  You remember the issue I had with the flat panels... of course I overbuilt mine, but... they were unusable in my environment... ](*,) ....
« Last Edit: May 31, 2015, 07:38:49 PM by Cutty Sark Sailor »
 


Offline Knorrli

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #15 on: May 31, 2015, 07:44:54 PM »
Don: that hover point doesn't work, neither IE nor Google Chrome. Unless you tell me that I have to hover 60 seconds or more.

Thanks for the tip

Uli

Offline va3mw

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #16 on: June 01, 2015, 10:23:27 PM »
Lots of good work going on here.  I sort of skimmed it as I am travelling.

I have the same antennas and I am running about 50ft of CAT 5 (unshielded as that is what I had to run a 'test' with) to my 2 1M loops sitting high in a Cedar tree.  I did add some Mix 43 chokes on the UDP cables though.

How well does it work if you run your Red in Automatic?  I am not sure if you tried that as well.  (I didn't look at  your noise floors).  However, I was just watching some of your signals and there certainly is something ringing unfortunately.   

I essentially built my antennas (1M loops) and for the most part, I just plugged them in and they worked.  I have seen them go in and out of interference mode, but I am pretty sure that was due to something totally out of my control (like my neighbour?).  I do need to rebuild them the correct Canadian way and use Hockey Sticks instead of the ripped Pine I used.

Mike va3mw
 
« Last Edit: June 01, 2015, 10:28:42 PM by va3mw »

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #17 on: June 02, 2015, 07:36:18 AM »
About the antennas.... If memory serves, some Hockey sticks have been shown (Gretzky, et.al. 1982-84) to puck up the net at high stroke levels.  My suggestion would be stay with the Ripped Pine... as the high ETOH levels in Ripped Pine would be more conducive to "don't care" and therefore have much less limiting on input than a merely High stick. It's possible that a Hockey Stick design, if constructed with a positive THC, might lead to an increased delay of up to 7+ days in fast response recovery, whereas Ripped Pine would normally be out of such hangover after 24-72 hours.

Seriously, 'Automatic' mode has remained pretty much 'Beta'  since 'day one'.  A few stations, with great environments, do well with Auto... most of us won't, simply because of location, and noisy environment, especially 'intermittent' signals.  There is a tendency, perhaps, to go "Auto" and turn on those two additional specialized filters without tracking down and mitigating the environment and other factors, which leads to degraded performance overall.  Up to the operator, of course.  I've always advocated the "stay out of Auto" paradigm, and resolve issues, if possible, the environmental changes in a stations' location, in order to determine the 'baseline' settings and location... since "auto" controls the system, not you, and you will see erroneous settings and levels, real-time vs. your actual settings.  The two 'extra' filter settings allowed were designed for very specific situations, and absolutely do not apply to most of us.

Again, when tracking 'interference' and 'noise' especially, I'll state this thought, regardless of other opinions:  Assuming we have a 'standard' 'recommended' antenna type, from it's signal through to the end, it may help some of us to think in terms of "Audio" and "Supersonic" processing rather than RF: Richo asks the other developers to read. http://sound.westhost.com/articles/balanced-2.htm
Is my noise Antenna induced, or is it system / ground related?  And most system issues seem to be grounding or power supply issues.

The network's primary area of interest is <500km from a given station.  Secondary interest are more distant strokes. Of virtually no significance are those signals <30KM.  And most of us run 'overkill' on antennas. A lot of our signals are sferics at distance.  We fall into the 'trap' of the much under-explained and misunderstood 'efficiency/effectivity' figures on the Participants page and on LMO.... If the "Regional" total network detects 1000 strokes, and 900 of them were farther than 1500 km from me, and my range is 1400km, I only detected 100.  My network 'efficiency/effectivity'  is 10%.  Does that mean I have a bad station?  On the other hand, those 100 strokes were within 500 miles of me, and I got 90 of them.  WOW!  90%
And my system will go Normal interference with extreme activity <30-200km. That's designed and expected. Especially with the network having good density of stations. I don't need to be sending all those extra signals, since those under <30km or so are virtually useless due to distortion.  Likewise, them old skywaves at distance are better left to the 4-18 nearer stations to the stroke.... all it does is raise that 'efficiency/effectivity'  percentage for my station... but had nothing to do with 'location' or other parameters... and the signals in both extremes lack the quality required, in terms of 'frequency' and phase content to improve the overall Network 'quality'.
We've got great stations, here in Region 3 - "Americas"... The other regions know it.  We've done well, and when BLUE hits, we'll be 'mentoring' a buncha people with far less technical knowledge, and background, then the Green and Red Builders possess... so we might practice some 'less technical' 'analogies' here and there as we have an opportunity... like "think of it as a stereo receiver" or "a microphone mixer", or a 'guitar tuner'... or your "cell phone and public WiFi"...
and see if they make sense...
« Last Edit: June 02, 2015, 07:42:03 AM by Cutty Sark Sailor »
 


Offline dfroula

  • Forecaster
  • *****
  • Posts: 551
Re: Interferenc Mode
« Reply #18 on: June 02, 2015, 09:15:03 AM »
Don: that hover point doesn't work, neither IE nor Google Chrome. Unless you tell me that I have to hover 60 seconds or more.

Thanks for the tip

Uli

Are you certain you are logged in? Logins seem to time out after a while. even if the "stay logged in" option is checked. You need to be logged in to see the time frame options. For me, hovering anywhere in the chart area brings up the pull down menu that allows selecting a time frame.

Best,

Don F.
WD9DMP

Offline Knorrli

  • Member
  • *
  • Posts: 36
Re: Interferenc Mode
« Reply #19 on: June 02, 2015, 12:49:05 PM »
I just found out that my network cable between controller and H-field amplifier is shielded, but there is no connection in the plug. The metal contacts at the outside are covered with plastic, so useless. Waiting for a new cable; keep you posted.

What are the distances to calculate the Effectivity S, M and L ratios?

@ Don: going from Blitzortung --> Participants --> M-button, no luck (when logging into WXforum with Blitzortung open in a separate tab, WXForum complains that I am already logged in. Must have something to do with the configuration of my computer.

@ Mike: I love your excursion into the philosophy of using Hockey sticks for building antennas. Is that why you think?  =D&gt;

Offline dfroula

  • Forecaster
  • *****
  • Posts: 551
Re: Interferenc Mode
« Reply #20 on: June 02, 2015, 01:57:50 PM »
I think curling brooms as spreaders would produce an antenna with lower self-capacitance. The frequency-sweep effect would help pull in those signals!  :roll:

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 3393
    • Frankfort Weather - TwinHollies WeatherCenter
Re: Interferenc Mode
« Reply #21 on: June 02, 2015, 03:53:44 PM »
I think curling brooms as spreaders would produce an antenna with lower self-capacitance. The frequency-sweep effect would help pull in those signals!  :roll:
Hmmm... don't know the effect of Iced and Stoned with a twist of Sweep vs. a High Stick with Icing called,  and / or out-cold Ripped Pine.  More research may be needed... .
« Last Edit: June 02, 2015, 03:57:06 PM by Cutty Sark Sailor »
 


 

anything