NZ Weather Forum

Gidday guys... I ahve been searching thru the old posts and have also seen on the net that people without "real" lightning detectors use there AM band radios....

So I have a few questions...and I have attached a pic of my WX sensor tower so you know what I amtalking about! I have a UNiden 9000XLT Bearcat Scanner that we use for monitoring the Kaipara Weapons Range and the Volunteer Fire Freq's.... the scanner aerial is attached to the top of my WX tower....

My scanner picks up electric fence "pulses" 9000V DC...so could it be used for lightning detection purposes? What freq in the AM band do you use for "sferic" detection? How do you measure distance to the strike?

Fascinating subject, one that has been inspired by seeing Steve's Boltek Graphic!!!

You get sperics well into the 80 metre band ie 3.6MHz but its better above 1400kHz and very good in the 160m band(above 1700kHz) if your radios go up enough.I have heard sferics on LW too however.and at night the distant storm systems will propagate like AM I occasionally can get from the USA or Hawaii.

Shepherds Valley WX wrote:Gidday guys... I ahve been searching thru the old posts and have also seen on the net that people without "real" lightning detectors use there AM band radios....

So I have a few questions...and I have attached a pic of my WX sensor tower so you know what I amtalking about! I have a UNiden 9000XLT Bearcat Scanner that we use for monitoring the Kaipara Weapons Range and the Volunteer Fire Freq's.... the scanner aerial is attached to the top of my WX tower....

My scanner picks up electric fence "pulses" 9000V DC...so could it be used for lightning detection purposes? What freq in the AM band do you use for "sferic" detection? How do you measure distance to the strike?

Fascinating subject, one that has been inspired by seeing Steve's Boltek Graphic!!!

Gidday Michael,

Thanks for the rapid reply...I can see I am going to have a problem with using the scanner and I should have seen it coming. The scanner freq range is 25Mhz - 1.3Ghz... I think 10m AM band is 28Mhz - 29.5Mhz from memory, and I cannot go lower than 25Mhz (6m band is around 50Mhz?).... do sferics appear in the 10m/6m band groups? I know I can monitor any freq between 25 and 1.3Ghz.... Look forward to your advice.

Cheers mate

I hink the lightning has to be local to give spherics above 25MHz but have heard them(locally) on FM (VHF) and causes fluttering and signals going momentarially out of stereo.Get a cheap SW radio to find the MUF of the lightning

Shepherds Valley WX wrote:Gidday Michael,

Thanks for the rapid reply...I can see I am going to have a problem with using the scanner and I should have seen it coming. The scanner freq range is 25Mhz - 1.3Ghz... I think 10m AM band is 28Mhz - 29.5Mhz from memory, and I cannot go lower than 25Mhz (6m band is around 50Mhz?).... do sferics appear in the 10m/6m band groups? I know I can monitor any freq between 25 and 1.3Ghz.... Look forward to your advice.

Cheers mate

Hmmmm, forgive my ignorance...but what is lightning "MUF"?

Maximum usable frequency.its where its used in ie recieving skywave etc,iyou go throuh the band on your radio and then the MUF is the last point you receive it and suddenly cuts off(ie with lightning the crackling/hiss stops)

Shepherds Valley WX wrote:Hmmmm, forgive my ignorance...but what is lightning "MUF"?

I just use my normal AM radio at home, tune it somewhere up high near 1500khz and find a spot where there is no radio station and a small amount of general hum coming through. When I say 'hum' I just mean the sound a radio makes when your not tuned into a station. When lightning goes off it'll make a scccchhhhhh! sound, generally you don't have to have the radio up very loud to hear it come through. Loud screchy sounds means somethings close while faint sounds means the storms are far away. I believe I've gotten strikes from way out in the Tasman sea from here in Chch. Over time you'll develop a sense I guess as to how loud the sounds are as to how far storms are away.

But by then you probably would've got a boltek!

you could use the dallas 1 wire lightning counter with weather display.....I have one here in use, and so does ricky in grey lyn...
works quite well at picking up strikes and counting them....but there is no direction information though.,....but that could be done somehow...

$$$$$$

Manukau heads observer wrote:works quite well at picking up strikes and counting them....but there is no direction information though.,....but that could be done somehow...

I had a look at the Dallas Semi site... the one wire detector looks pretty good...do you buy them online from overseas Brian? or is it just as easy to buy one ready made and ready to go? My PC Board/Electronic soldering skills are not that flash despite being a sparky!! (Ok so I was an industrial electrician!)

I'd be keen to hear more info and how it works for you guys....

Shepherds Valley WX wrote:Gidday guys... I ahve been searching thru the old posts and have also seen on the net that people without "real" lightning detectors use there AM band radios....

Fascinating subject, one that has been inspired by seeing Steve's Boltek Graphic!!!

Hi Macca,
I found a "lightning detector" in the readers contributions in Everyday and Practical Electronics (EPE) that I subscribe to. It could be built on the small bit of strip board. I have not built it but it looks like it would work. You can download the page here
http://weather.northcott.co.nz/instrume ... tector.pdf

There is a constructional article on a thunderstorm detector in the Nov edition (out in about 2 weeks) that claims it will detect a thunderstorm by the high potential difference between atmosphere and ground.
Hardly a replacement for Stephens detector but it may be useful.