Author Topic: SaratogaWX Blitzortung build diary.  (Read 10187 times)

0 Members and 1 Guest are viewing this topic.

Offline scarecrow93

  • Member
  • *
  • Posts: 26
Re: SaratogaWX Blitzortung build diary.
« Reply #50 on: October 09, 2013, 08:20:58 AM »
What gain are you running at?  If you're running at 10/4, under the current weather situation you're not going to get much.

When I first started my test on the 12 inch (30 turn, 18ga wire)...I started off at 10/10 and ended going up from there.

I just built an 8 inch (45 turn, 18ga wire) ball antenna on Friday to see how low I wanted to go in regards to the size.  The starting gain was much higher...around 16/16.

I'd probably start at 16/10 with yours and go from there.

Lance
Huntingtown, MD  #724
~Lance
#724 - Huntingtown, MD(Aug 2013 - Feb 2014)
Owings, MD(Feb 2014 - Feb 2015)
Annapolis, MD(Late Feb 2015)

Offline saratogaWX

  • Administrator
  • Forecaster
  • *****
  • Posts: 7498
  • Saratoga, CA, USA Weather - free PHP scripts
    • Saratoga-Weather.org
Re: SaratogaWX Blitzortung build diary.
« Reply #51 on: October 09, 2013, 11:05:00 AM »
Hi Lance,

Thanks for the gain advice -- I will crank up the gain as soon as I can isolate where the strange 60Hz spikes are coming from.  I've tried running higher 10:4, but currently, it only moves the controller into interference mode due to the false-positives provided by the spikes :(

Best regards,
Ken
Ken True/Saratoga, CA, USA main site: saratoga-weather.org
Davis VP1+ FARS, Boltek-PCI/NexStorm, microSferics ToA, Blitzortung RED, GRLevel3, WD, WL, VWS, Cumulus, Meteobridge/hub
Free weather PHP scripts/website templates - update notifications on Twitter saratogaWXPHP

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3320
    • Carson Valley Weather
Re: SaratogaWX Blitzortung build diary.
« Reply #52 on: October 10, 2013, 12:18:11 AM »
Ken,

Based on what I've experienced in the ham radio arena, sometimes, when attempting to locate an interference source, you will get better results by rotating the antenna to get a null in the readings. Nulls tend to be sharper (narrower due to them being lower in amplitude) and thus easier to find than a peak in signal.

I would look for a wall-wart (transformer used for all kinds of devices today - ie, laptop power supply, cell-phone charger, etc, etc), some kind of light dimmer or even the door-bell transformer to be your problem source. Do you have lamp in your door-bell button outside? All of these things could be sources of interference. Is this 60Hz signal present day and night or just at some particular time of day?

You may also want to begin turning off the circuit breakers for different areas in your house. That would help narrow down the location of the circuits causing the problem. Sorry, I know that means resetting your digital clocks but...

Good luck finding this elusive signal...

Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37s101,
StartWatch, VirtualVP, VPLive, Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline miraculon

  • Sunrise Side Weather
  • Forecaster
  • *****
  • Posts: 3465
  • KE8DAF
    • Sunrise Side Weather in Rogers City MI USA
Re: SaratogaWX Blitzortung build diary.
« Reply #53 on: October 10, 2013, 06:49:09 AM »
I would try using an AM radio to see if you can find anything. I have had mixed results with this, sometimes the radio finds noises that are not related to the lightning detector response.

I have used several different "sniffers" and have been able to eliminate some noises. I have an infrequent severe noise of unknown origin.

I noticed that my "green" detector responded and went into interference mode when the wife was running the vacuum cleaner. It could be a motor. Cutty has night-time outside light problems. Unfortunately, we live immersed in RFI from a lot of sources. Best of luck tracking them down, W3DRM has some good advice there and should give you some ideas.

Greg


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

Offline dfroula

  • Forecaster
  • *****
  • Posts: 543
Re: SaratogaWX Blitzortung build diary.
« Reply #54 on: October 10, 2013, 09:36:17 AM »
I found the best sniffer for noise detection is the amp itself. Try connecting the monitor pins on the amp to a stereo headphone jack and plug the amp into a high-impedance input audio amplifier and listen to the signal. It is very easy to distinguish normal low-level 60 Hz background hum from noise from motors, 60 Hz harmonics from a bad "wall wart" power cube or other sources. With stereo earphones and each antenna connected to left and right channels of the amp, the nulls from the antennas are a very good way to trace the direction and type of interference. I used a simple "CMOY" headphone amplifier for the purpose. The CMOY is a simple single-chip headphone amp. Try Googling for the schematic. A PC soundcard would work, but then you are dealing with processor noise from the computer. An old set of PC powered speakers may work well.

Don

I would try using an AM radio to see if you can find anything. I have had mixed results with this, sometimes the radio finds noises that are not related to the lightning detector response.

I have used several different "sniffers" and have been able to eliminate some noises. I have an infrequent severe noise of unknown origin.

I noticed that my "green" detector responded and went into interference mode when the wife was running the vacuum cleaner. It could be a motor. Cutty has night-time outside light problems. Unfortunately, we live immersed in RFI from a lot of sources. Best of luck tracking them down, W3DRM has some good advice there and should give you some ideas.

Greg


Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3320
    • Carson Valley Weather
Re: SaratogaWX Blitzortung build diary.
« Reply #55 on: October 10, 2013, 01:00:55 PM »
Here's a link to the CMOY article. This site includes a complete, and detailed, description of the CMOY amp and a full listing of where to get the parts. It appears to be well done and should be easy for anyone to build.


Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37s101,
StartWatch, VirtualVP, VPLive, Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline miraculon

  • Sunrise Side Weather
  • Forecaster
  • *****
  • Posts: 3465
  • KE8DAF
    • Sunrise Side Weather in Rogers City MI USA
Re: SaratogaWX Blitzortung build diary.
« Reply #56 on: October 10, 2013, 03:04:26 PM »
That circuit has a gain of only 11. (1+(10k/1k)). Just less than 21dB.
Is that enough to hear anything?
It might be for a strong enough noise source. If the amp remains stable, you could increase the 10K feedback resistor to get more gain.

Greg


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

 

anything