NVIS equipment

[Skean Dhude]

There must be hams all over the place including close to Ken. Perhaps we should find out if anyone from the ham area can help anyone. Do any of our hams know the way to find out about other hams.

[NorthernRaider]

(10 July 2012, 18:56)Skean Dhude Wrote: There must be hams all over the place including close to Ken. Perhaps we should find out if anyone from the ham area can help anyone. Do any of our hams know the way to find out about other hams.

!!!!!!!!!!!! I know how to find a ham near Kenny, we set a trap for one....... A HAMBUSH !!!!!!!!!!!!!

[Lightspeed]

(9 July 2012, 19:03)Skean Dhude Wrote: They are the same price, what is better the 1340 or the 1380?

They are identical radios just different frequencies.

1340 is 40 meter band ( 7Mhz) which will work NVIS in daylight hours

1380 is 80 meter band ( 3.5Mhz) which will work NVIS at night

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(9 July 2012, 20:44)Paul Wrote: Hi NR, hows the back?

NVIS for the unknowing is "ham speak" for Near Vertical Incidence Skywave or low frequency transmitters working from 1.8mhz to 10mhz with vertical or inverted v aerials.

Sort of CB sets working at low frequencies. (CB sets work at 27 Mhz)
Typical modes include morse code and SSB.

You'll need a ham foundation licence to work this and then you are limited to 10 watts.

Problems include:-
Aerials are BIG typically in an inverted v 35' long.
Aerials usually need to be tuned in using an aerial tuning unit.
Both ends need to be working NVIS to achieve reliable communications.
You'll need a ham licence.
and of course if you're working morse, you'll have to learn morse!!!!!!!!!!!

---

Morse is fun.
It's not quite just learning the code though it's also about the timing i.e.

1. A dot is worth 1 unit (you decide how long that is).
2. A dash is equal to 3 dots
3. The space between parts of the same letter is equal to 1 dot
4. The space between two letters is equal to 3 dots
5. The space between two words is equal to seven dots.

Shall I go on? (Y) -.-- or -. (N)

Would you like the morse code now ? (Y) -.-- or -. (N)

Hi Paul,

Small correction NVIS antennas are indeed long but they are always horizontal-ish They are also low to the ground. Some people rig them just a couple of feet off the deck. Objective is to use the ground as a reflector to send the signal straight up. ( its the signal that's near vertical nnot the antenna)

End fed half waves can therefore be moiunted discreetly along the top pf woode fences. the antennas does not have to be a straight run to work.

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(10 July 2012, 18:56)Skean Dhude Wrote: There must be hams all over the place including close to Ken. Perhaps we should find out if anyone from the ham area can help anyone. Do any of our hams know the way to find out about other hams.

Look up local radio clubs and contact them. A face to face meeting will quickly establish the guys who'll help and thaose that'll hinder :-)

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(9 July 2012, 23:00)Juice Wrote: 12. Power supplies and charging systems, most likely 12v

Very easy to make permanent magnet motor (fairly cheap too).

http://www.energy-creator.com/the-coil.php

Then use one of those plastic tool boxes to house it, along with a 12v battery winding handle and pulley (make your own).

http://www.youtube.com/watch?v=r0IyjsPTx...r_embedded



Cheers Juice.

Excellent idea Juice.

Isn't it easier to just rig up a car alternator, or better still a 12v dynamo if they can still be had?

LS

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(10 July 2012, 19:13)NorthernRaider Wrote:

(10 July 2012, 18:56)Skean Dhude Wrote: There must be hams all over the place including close to Ken. Perhaps we should find out if anyone from the ham area can help anyone. Do any of our hams know the way to find out about other hams.

!!!!!!!!!!!! I know how to find a ham near Kenny, we set a trap for one....... A HAMBUSH !!!!!!!!!!!!!

Good to see that the happy pills are still working NR

[Lightspeed]

TenTec T1380 demonstration on NVIS

This is a video of a converstaion in morse on a Ten Tec low power T1380 radio using NVIS propogation: The contact is on the on 80 meter band. Its described as typical morning NVIS propagation, distance 207 miles (333km) using RF power output of about 3 watts

http://www.youtube.com/watch?v=amvIb6fwuN0

[Paul]

A demonstration of the problem that all non hams and even some experienced hams encounter.
Morse code.
Without the "tele text" on this clip, for most of you it's just pretty tones.

Now watch and listen to this-[Utube linky]

Two CBers chatting away between Aylesbury to Germany.
A range of 400 miles(ish).

Hands up all those who prefer voice to key (morse code).
Keep them raised if you like the idea of not having to get a licence.

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(11 July 2012, 17:15)Paul Wrote: A demonstration of the problem that all non hams and even some experienced hams encounter.
Morse code.
Without the "tele text" on this clip, for most of you it's just pretty tones.

Now watch and listen to this-[Utube linky]

Two CBers chatting away between Aylesbury to Germany.
A range of 400 miles(ish).

Hands up all those who prefer voice to key (morse code).
Keep them raised if you like the idea of not having to get a licence.

you can put your hands down now!

[Lightspeed]

(11 July 2012, 17:15)Paul Wrote: A demonstration of the problem that all non hams and even some experienced hams encounter.
Morse code.
Without the "tele text" on this clip, for most of you it's just pretty tones.

Now watch and listen to this-[Utube linky]

Two CBers chatting away between Aylesbury to Germany.
A range of 400 miles(ish).

Hands up all those who prefer voice to key (morse code).
Keep them raised if you like the idea of not having to get a licence.

---

(11 July 2012, 17:15)Paul Wrote: A demonstration of the problem that all non hams and even some experienced hams encounter.
Morse code.
Without the "tele text" on this clip, for most of you it's just pretty tones.

Now watch and listen to this-[Utube linky]

Two CBers chatting away between Aylesbury to Germany.
A range of 400 miles(ish).

Hands up all those who prefer voice to key (morse code).
Keep them raised if you like the idea of not having to get a licence.

you can put your hands down now!

Different sort of propogation Paul.

The CB is single bounce skip. almost everything between the UK and German station will have been unable to hear either of those stations.

The 200 odd miles on the NVIS clip, and everything in between those two stations would have been able to catch both sides of that conversation. ( incidentally it would have worked using SSB voice mode too, but the transmission power would have had to be a little higher than 3w.

Yes Morse is hard work I agree, but its also the most penetrating of signals and also employs the simplest electronics to generate it..

I've put my hand down now and an about to go down to the pub for a well deserved pint :-)

Cheers

LS

[Juice]

Hi Lightspeed,
Yes you can use a car alternator; if you can spin it fast enough! - so best used on a combustion engine generator, unless you modify the alternator with permanent rare earth magnets - expensive!
How about making a generator from scratch and bespoke to your needs? Enter...

http://www.energy-creator.com/the-coil.php

I bought this guys video and highly commend it.
It explains how to make a powerful generator that creates power even from a low rpm - unlike the car alternator.
Using plain and simple tools, the generator is very easy to make and is quite novel!
See his videos!!

For more info on different electric generators, see link below

http://www.otherpower.com/otherpower_win...ators.html

Hopefully something like this (see earlier post) could help with our comms or power needs; now, in the field or post 'doo-doo hits the turbine'.

Cheers Juice.

[Paul]

Propogation is not always what it seems and the books don't account for "magic". You know the effect LS, it shouldn't work but it does.
i.e. The DV27 on the biscuit tin set up talking to Italy, etc.

For instance. Dorset CB'ers were moaning about Scottish signals swamping them at S5 this week. They in turn are chatting back at 4 watts FM.

Yesterday, our group was working a day net with the hub based in Hitchin, Herts. Huge amounts of atmospheric noise.
All 12 watt stuff, FM, most of us with 1/2 or 5/8 vertical dipoles, all mobile.

Mileage and signal strength [S1-5]
Hitchin
To Poole, Dorset. 134 miles [Variable S2-4]
To Norwich 90 miles [S3]
To Manchester 168 miles [Variable S2-4]
To Worcester 116 miles [S4]
To Woodhall Spa (Lincs) 111 miles [S2]
To Bedford 17 miles [S1]

As I said above, magic. Now I'll admit we've all got damn good rigs, receivers tuned WAY above factory spec but for 7 out of 9 of us holding decent conversations on such a bad noise day, it must have been magic.
The other two? Couldn't hear each other some 23 miles apart let alone us.

[Lightspeed]

(11 July 2012, 21:27)Juice Wrote: Hi Lightspeed,
Yes you can use a car alternator; if you can spin it fast enough! - so best used on a combustion engine generator, unless you modify the alternator with permanent rare earth magnets - expensive!
How about making a generator from scratch and bespoke to your needs? Enter...

http://www.energy-creator.com/the-coil.php

I bought this guys video and highly commend it.
It explains how to make a powerful generator that creates power even from a low rpm - unlike the car alternator.
Using plain and simple tools, the generator is very easy to make and is quite novel!
See his videos!!

For more info on different electric generators, see link below

http://www.otherpower.com/otherpower_win...ators.html

Hopefully something like this (see earlier post) could help with our comms or power needs; now, in the field or post 'doo-doo hits the turbine'.

Cheers Juice.

Makes sense Juice,

I do not have a human powered generator yet. My thinking was to rig up an alternator on my bike training rig somehow, or even modding a rear wheel to act as a drive pulley ( with the bike in the stand.) Of course a low tech replaceable drive belt would also be needed.

I've also noticed on e-bay that you can pick up ex army hand generators designed for the Clansman radio kit. These are built combat and squaddie-proof, so should be extremely durable. Snag is that they are 24 volt, but they could be used to charge up a pait of 12v batteries wired in series of course.

Primarily I'm going down the Photo Voltaic Solar cell route so as to collect energu for free.

I see human powered generation as either an emergency solution or as a way both exercising and capturing the energy expended in that exercise during the extended lay-low period that I am planning for.

Do you really thing home made generators are a viable project for non-mechanical-toolshop savy folk like me?

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(12 July 2012, 04:17)Paul Wrote: Propogation is not always what it seems and the books don't account for "magic". You know the effect LS, it shouldn't work but it does.
i.e. The DV27 on the biscuit tin set up talking to Italy, etc.

For instance. Dorset CB'ers were moaning about Scottish signals swamping them at S5 this week. They in turn are chatting back at 4 watts FM.

Yesterday, our group was working a day net with the hub based in Hitchin, Herts. Huge amounts of atmospheric noise.
All 12 watt stuff, FM, most of us with 1/2 or 5/8 vertical dipoles, all mobile.



Mileage and signal strength [S1-5]
Hitchin
To Poole, Dorset. 134 miles [Variable S2-4]
To Norwich 90 miles [S3]
To Manchester 168 miles [Variable S2-4]
To Worcester 116 miles [S4]
To Woodhall Spa (Lincs) 111 miles [S2]
To Bedford 17 miles [S1]

As I said above, magic. Now I'll admit we've all got damn good rigs, receivers tuned WAY above factory spec but for 7 out of 9 of us holding decent conversations on such a bad noise day, it must have been magic.
The other two? Couldn't hear each other some 23 miles apart let alone us.

Paul,

You're right it is magic. This is precisely why I am fascinated in radio... there's still lots of stuff that is unexplainable, not least how flea power 1/2 watt signals can be detected on the other side ofthe planet.

The Dorset Scotland contact is explainable. its single skip again. probably off what is called the E layer. This is a sporadic summer phenomenum. Its fairly reliable and predictable. We can plan for it in our CB based coms prepping.

Yesterday's consitions are more exciting. What you were getting very closely corresponds with NVIS. If it was, it was a very rare phenomenum. Fascinating. Its exactly what we need for longer range UK coms. But we need to select frequencies where it will be fairly reliable for the task, not just possible on rare and exceptional occasions.

[Lightspeed]

[quote='Paul' pid='18392' dateline='1342063079']
Paul,

Your FB group's event yesterday got me thinking and researching before work today.

Its possible that you had a dense sproradic-E cloud of ionisation right overhead and that it was dense enough able to reflect 11m transmissions straight back down to earth (NVIS) this accounts for the high noise floor you experienced, and also the contacts that were achieved in what would normally be the skip zone.
e-layer is 95Km to 120Km high by the way.

Web researching indicates this to be very rare indeed at CB (27Mhz)frequencies.