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Old 28th March 2014, 12:53   #1
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Default Off-Road Communication

Off-Road Communication (Part 1 - Hand Signals)

What is the Communication Loop?

A sender, sends a message, through a medium, where the message is distorted by a noise, to a receiver, who receives the message, and send a feedback.

In an off road scenario

Sender (Spotter/Marshal)

Message (spotting instructions / Situation Reports)

Medium (Hand signals/Verbal Cues/RT Comm)

Noise (Ambient Noise, cheering, shouting, engine noise, static, terrain obstructions etc)

Receiver (Vehicle Driver, who needs to receive the message to safely continue on the route)

Feedback (Steering Inputs, Course correction, Stop, or awaiting repeat of instructions)

Why are Hand Signals used?

1) Its economic, than equipping each vehicle and spotter/marshal with RT set.
2) It is easier than shouting aloud over the noise of vehicles, over a distance.
3) It is more effective, when there are a large number of participants or a course over few days.
4) It is not as distracting, a RT communication in cabin, in the ear.

Hand Signals
There are very few common international Hand signals for Off-Roading.
The ones that have been adopted are from the military, aviation, Hauling & Recovery and Crane users.

Every group or team has their own variation of the common hand signals, and are easily adopted and understood by people who are new to them, provided they are not complicated.

Factors for Driver’s misunderstanding the spotters hand signal
1) The Driver and / or Spotter/Marshal is unaware of the basic hand signals
2) The spotter isn’t confident or tired, and the signals are sloppy or contradictory.
3) Not able to see the hand signals due to the terrain, steep climbs or Steep Drops, foliage etc.

The Terra-Tigers use the following basic Hand Signals, which we have evolved and adopted over the years.

1) Stop
– Hands held High and crossed; with closed fist / One hand with closed fist

2) Move up /forward / come here – One / Two Hands held up with open palms, towards Spotter / Marshal, moving at the shoulder or elbow, calling the driver towards himself.

3) Turn Left – The Spotter/Marshal always indicate with reference to the Vehicle / Driver’s Orientation; usually facing him. So the Marshal will hold up one / both hands, and he will indicates his right (Vehicle Left) with his right hand open Palms facing the Vehicle.

4) Turn Right - The Spotter/Marshal always indicate with reference to the Vehicle / Driver’s Orientation;usually facing him. So the Marshal will hold up one/ both hands, and he will indicates his Left (Vehicle Right) with his Left hand open Palms facing the Vehicle.

5) Slow Down – Both Hands chest level, Palms facing out, slowly, pressing down.

6) Back Off- Both hands held high, palms facing out, and slowly pushing away. Or Both hands held high, palms facing in, rotate the wrists inwards, in a circular motion.

7) Throttle Modulation – Right hand held a chest level, and palms facing out, wrist rapidly fanning down.

8) Winch – Paying Out / Sending the Cable Out – Hold up Right Hand circle with index finger and pull the palm towards yourself.

9) Winch – Heaving in / Taking in the Cable - Hold up Right Hand circle with index finger and point towards the Driver / Vehicle.

10) Pulsing the winch /Intermittent winching – Hold up the right hand, make and circle with your thumb and fingers, rapidly open and close the circle with the fingers.

Some links

http://www.hummerxclub.com/docs/hand_signals.pdf

http://www.fourwheeler.com/features/...communication/

http://www.arrivealive.co.za/pages.aspx?i=2908

I would request off-roaders and outdoor enthusiasts to contribute to this thread, and give necessary suggestions or improvements.

Regards,

Arka
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Old 28th March 2014, 13:17   #2
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Default Re: Off-Road Communication

Very good thread Arka.

Standardising signals is the correct way forward so that the drivers are not confused by different hand signals at various events.

Here are some pictorial illustrations from my study materials.

These are international marshal signs. Ofcourse some need to be adapted to our offroad:

Off-Road Communication-screen-shot-20140328-1.09.40-pm.png

Off-Road Communication-screen-shot-20140328-1.09.51-pm.png

Source: British Pocket Guide to Marshalling

These are winch signals from my personal copy of Ken Sibly: The New Zealand 4 Wheel Drive Handbook. Shoal Bay, 2004.:

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Old 28th March 2014, 14:03   #3
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Default Off-Road Communication - Part2 Walkie Talkies

Part 2 – Radio Trans-Receivers / 2 Way Radios/ Walkie Talkies

What is a Walkie-Talkie? It is a communication device, where you can send and receive messages alternately over a “local” network, tuned to the same channel.

A Handheld set is carried by a person.
A Base Station is usually vehicle mounted and used to increase the transmitting power of the network.

What are the advantages of using Radio Trans-Receivers outdoors?
1) You can create a local network.
2) Improve situational awareness, because everyone receives the message.

Common types used
1) FM Sets – Regularly Walkie- Talkies available in 2 Handset packs using AA batteries, ideal for use over a short Range 2-5Kms Line Of Sight.

3) UHF/VHF Walkie-Talkies – Used by the Police/ Military and available for hire, using a licensed channel. Range 5-25Kms

4) CB Radio – Used largely by Call Taxi Network in the city, these operate on a fixed, free channel, which anyone and hear. Range 20-40Kms.

From TPC2006-2009 we used the FM Walkie –Talkies, they were good as a start, but range was bad, and poor battery life, voice clarity was poor.

In 2010 we switched to UHF/VHF Handheld sets and 3 Base Stations, this gave us excellent coverage good battery life and good voice clarity, but the sets required a lot of care and temporary mounting inside the vehicle was not safe.

In 2011-12, we went in for the UHF/VHF (Motorola/Siemens) sets, these gave us good coverage, good battery life and good voice clarity, but the handheld sets were quite heavy.

Currently we are using Talkpro, their biggest advantage is they come with a Hands free set which is clipped to the ear, and a remote PTT Switch this makes it more useful while driving.

The BODA off-roaders have been using handheld and vehicle mounted CB Radios since 2011 and I would request them to share their experiences and suggestions on this thread.

Basic Walkie-Talkie usage
1) Brief the users on
a) User names/identity i.e Satya & Hari, at SS1
b) Preset Channels.
c) On/off/Volume/Channel functions.
d) Changing /Charging battery
e) PTT Function.

2) Send clear and short messages.
3) Protect the Set from the elements, physical damage and theft.

How to send a message on a Walkie-Talkie
1) Identify the Target Receiver, since the network can have more than 2 users, and on larger networks the message may become confusing.
SS1,pause SS1, pause SS1, this is SS2 OVER
or
SS2 for SS1, pause SS2 for SS1 OVER.
2) Acknowledge the Sender, the acknowledgement, alerts the sender to send the message, indicating the Receiver is ready and Channel (Network) is free.
Come in SS1 OVER

3) Send the Message, The message must be short and clear, think out the message, say it in your head, then press the PPT and send it out.
SS2, Teams 111, and 312 are heading to SS4 OVER.

4) Receiver Acknowledges the Message. This is to ensure that the Target Receiver has indeed received the message.
COPY THAT SS1 or ROGER THAT SS1

5) Sender Acknowledges Receipt, if there is a Part 2 of the Message, that is sent now, or the Sender closes the loop after receiving the “feedback” to allow further communication between other users.
SS2, Teams 112, and 113 are stuck near SS4, Over
Or
SS1 OVER AND OUT

Good Practices while using Walkie Talkies
1) Avoid Loose Talk and Chatter.
2) Identify the Receiver and Sender.
3) Think Out the message, Talk it in your head and then Speak out the message.
4) Be alert and follow every communication.
5) ONLY the initiator of the conversations can close it with OVER & OUT
6) Don’t cut-off any communication till you hear OVER & OUT

This is just an example, as the entire group gets more familiar, messages can be relayed to other users who are not in range.

Regards,

Arka
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Old 7th April 2014, 21:10   #4
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Default Re: Off-Road Communication

Interesting topic...

The conduct of wireless operators are very well listed down by Arka.

BODA does not use CB Radios, but HAM Radio. To legally operate HAM Radio in India, a license is required. This is issued by Indian Wireless Telegraphs(Ministry of Communication & IT). All the BODA Marshals have written this exam, and possess this license. Though CB radios were sampled by BODA, their effectiveness falls short of their expectation, the CB radios weren't performing in wooded and hilly areas. Usually the OTRs are around old quarries where the elevations are pretty differant for even for every 200 meters. The HAM radios offer crystal clear communication comparatively. You may read more about HAMS here.

http://www.indianhams.com/

Regards
Andy

Last edited by Grace : 7th April 2014 at 21:14.
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Old 8th April 2014, 10:39   #5
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An Update,

This article has appeared in todays (8th April'14) Deccan Herald newspaper, page no 4, top left corner. Interested BHPians keen to get license for HAM radio operator may contact the coordinates mentioned in there.

Regards
Andy
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Old 8th April 2014, 16:07   #6
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Default Re: Off-Road Communication

Also good to know that currently only HAM and CB are legal stuff in India. Walkie-Talkie (FM based) is not legal and can land you in trouble. (PS - I had the inbuilt battery pack ones compared to the AAA ones, and they were faar better in clarity and range. But as the battery came closer to 25-30% levels the sound quality and range withered away)

To learn and get HAM there is a training course and a cool-off period after you pass the exam (right, Andy?).

CB - there is a document available on internet/Tbhp to say its legal for street use and no licence is needed. One deterrent is it looks like a cop-cars' dash mount unit and you be can flagged down by the enthu-cutlet cop for questioning.

Good to know -

1) Walkie-Talkie can be picked up at 4-5K/pair from USA.
2) CB with Antenna costs about 5K from USA, 2Ft antenna sucks, min 6Feet will help in real world forest/jungle trail, signal absorbtion by foilage is too high.
3) HAM - Exam+Equipment is 10ish, can ham users clarify?

Someone should try and procure the SOS/Serial Flare/Aerial Flare (the diwali rocket type red light that is shot from a pistol into the sky), it IS a helpful tool.
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Old 8th April 2014, 16:31   #7
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Default Re: Off-Road Communication

OT: talking about flares, or rather 'locate me tools', there is a very commonly used service in Europe, Australia and US called SPOT.

A small GPS machine when pressed sends out the GPS coordinates to a preprogrammed number / email.

Unfortunately service not there in India. Available everywhere else.

www.findmespot.com
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Old 8th April 2014, 18:00   #8
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Default Re: Off-Road Communication

Quote:
Originally Posted by Tejas@perioimpl View Post
OT: talking about flares, or rather 'locate me tools', there is a very commonly used service in Europe, Australia and US called SPOT.

A small GPS machine when pressed sends out the GPS coordinates to a preprogrammed number / email.

Unfortunately service not there in India. Available everywhere else.

www.findmespot.com
Why not in India. There are personal GPS trackers available which take a normal sim card.
You press the panic button and it sends your coordinates to upto 10 numbers pre-programmed in the device.

You also have the option of GPRS to send data every 30 seconds to a traccar server(free to setup if you have a machine with atleast 512MB(1024MB recommended) machine.
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Old 8th April 2014, 19:36   #9
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Default Re: Off-Road Communication

This one doesn't use cellular service. For sim based trackers you need coverage. This one has some setup to work with satellites directly.
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Old 8th April 2014, 22:13   #10
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Default Re: Off-Road Communication

@SVS, the CBs have limited range, something like around 4-5 kms and that too in clear line of site, you are done in by any change in elevation, no matter how tall your antenna is. This was tried out in BODA recce, in fact hollering on top of our voice was more effective.

The FM is clearly not a winner again due to it limited range.
HAM radio has HF(High Frequency), VHF(Very High Frequency) & UHF (Ultra High Frequency), these enables you to connect with another person more than half way across the world. Infact the lecturer in the course informed us that it was possible to use the radio for voice communication upto the moon also.

HAM+Licence may be 10ish in cost, plus there is a process to get license, you wont be handed one right after you pass the test, there will be separate address verification by Police department, who will actually come and 'interview' your neighbor to know whether you actually live there or not. The licence period is for 20 years, thereafter renew every 20 years. Fee for 20 year is Rs 1000/-. The HAM community is very vibrant despite the advent of cellular phone, it has its own fan base. The lecturer claimed that every 2nd citizen of Japan is a HAM operator, therefore half of Japan is on HAM :-)

Regards
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Old 9th April 2014, 01:16   #11
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Default Re: Off-Road Communication

Quote:
Originally Posted by Grace View Post
HAM+Licence may be 10ish in cost, plus there is a process to get license, you wont be handed one right after you pass the test, there will be separate address verification by Police department
For getting a HAM license, you first need to take a test which is conducted some 3 times a year (in Bangalore). You need to register for the test a couple of months in advance. The test has 2 parts, one on the HAM rules and regulations and another on basic electronics. If you have an engineering degree or have studied electronics for BSc, you are excepted from taking the electronics part of the test. Apparently, even after clearing the test it takes about an year to get the license due to paper work and police verification and stuff.

I was planning to take the test last year but couldn't since I had to travel for work. Have to apply for the next exam.

Bangalore guys can attend classes and take the exam at the Indian institute of HAMs http://www.indianhams.com/home.asp
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Old 9th April 2014, 09:47   #12
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May be I should take this test as I only have to take just 1 part, the HAM rules. I do have a BE in Electronics. Police verification may be tougher since I live in two places.
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Old 9th April 2014, 21:59   #13
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Not really Samu,
Police will just visit the address given by you in the application form, they will actually interview your neighbor irrespective whether your home or not. Infact they came in my absence and interviewed a moron neighbor, who called me to inform that "Police came in search of me regarding a theft of radio".

Make sure you have some intelligent neighbor, put in a word to them in case you will be out.
I experienced this because I gave the address of my new house that I am planning to shift in next 10 days and this happens to be in bangalore rural district, my neighbors are actually villager kind.

Ofcourse you can escape the electronics part and just do rules & regulations part.

Last edited by Grace : 9th April 2014 at 22:00.
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Old 19th June 2014, 10:20   #14
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This thread caught my attention as I am also an Amateur Radio Operator.

Quote:
Originally Posted by ex670c
1) FM Sets – Regularly Walkie- Talkies available in 2 Handset packs using AA batteries, ideal for use over a short Range 2-5Kms Line Of Sight.
These walkie talkies comes in two flavours - the PMR and FRS. They generally operate on the UHF spectrum. PMR is on 446Mhz, where as FRS is on 462Mhz. How ever there is a catch. These radios can only transmit at 0.5 Watts of power. With this the coverage is very very minimal. In a concrete jungle I live, these radios don't even give a coverage of 1 to 1.5kms. On highways the ranges are better and you should get 1-3kms. These radios have good coverage if the area is empty flat land. A couple of my relatives had got these sets and use them when going on convoy mode. BTW, these sets are illegal to be used in India. The belief is that these frequencies may be used by the police, but I am sure the police also knows that it is better to avoid this frequency. With 0.5 Watts the chances of these sets messing some up other communication channel is very less. A normal walkie talkie used by the police can transmit at a power of 5W (10 times more than these PMR and FRS radios).

Quote:
3) UHF/VHF Walkie-Talkies – Used by the Police/ Military and available for hire, using a licensed channel. Range 5-25Kms
The walkie talkies generally have power output of 5 Watts. With pure line of sight, the walkie talkies can communicate to a distance of around 5-10kms. Base stations (which are kept inside homes or vehicles) how ever can transmit at 25W (and some times even more). So with a good antenna, these can easily cover distances over 25kms. Wireless Planning Cell (WPC) has ear-marked some frequencies for Rally communications etc. Licensing has to be done well in advance. In a K1000 rally which I took part around 5 years back, we had a setup of around 5 channels. One channel was a "repeater" channel, which ensured that the entire rally area was reachable on wireless. The other four channels were more of local channels, only covering one part of the rally area.

Quote:
4) CB Radio – Used largely by Call Taxi Network in the city, these operate on a fixed, free channel, which anyone and hear. Range 20-40Kms.
CB Radios are the new entrant to the field. A set of frequencies on 27Mhz has been delicensed by GoI few years back. But there is a catch here again. CB Radios cannot transmit at more than 5Watts power. And CB Radios will never have "repeaters", a key tool to increase the communication range. So this puts CB radio at a disadvantage, because they are slightly powerful (and legal) versions of the FM set mentioned in Point #1.

From what I have observed in the city I live, Call Taxis do NOT use CB Radio for communication. They have a dedicated set of frequencies, and also have a repeater installed on a tall building in the city. The drivers have channels configured for them. With the arrival of MDT etc., many companies have done away with radios these days.

Quote:
SS1 OVER AND OUT
This is incorrect radio procedure. How ever "Over & Out" has been popularised by movies/serials etc., and perhaps i gives a very serious impact. But in real usage these terms are mutually exclusive. It is either "Over" or "Out". Over means "Over to you". This means that the current speaker is done, but is expecting a response from the listener. Where as "Out" means, the speaker is done with the communication and does NOT expect any response from any one. So if SS1 is done with his communication all he needs to say is "SS1 OUT", or "This is SS1 OUT".


Amateur Radio (HAM) communication goes beyond all these problems, but comes up with its own set of new problems . 1. It requires a license. Licensing is a slow process and the lead time is around one year. It includes mandatory police verifications etc.
2. "Mobile" use is not really sanctioned by WPC. When stations are to go "mobile" they are to get a special permit for the same. HAM organisations are trying to get this rule changed, and at present it is not very strongly enforced.
3. Since HAMs require a license, and will have a unique call sign it just cannot be used by any one having access to a wireless set.

On the positive side:-
1. HAMs can operate a minimum power of 10W. Higher grade HAMs can operate at a power of 25W.
2. HAMs have the benefit of repeater stations. Repeaters are devices which can capture a radio signal and re-transmit at high power. These are generally placed on tall buildings or on hill tops. So with such a facility a HAM on a mobile at Vijayamangalam Toll Booth (on NH47), can communicate with a HAM in Electronics City, Bangalore - 300kms away !!! That too by transmitting at 10W power. The hero in this operation is the repeater station at Yercaud hills near Salem. The only private party who have a similar setup is the KPN bus service operating across the states of Karnataka, Tamil Nadu and Kerala. They have a special license for the same (just like Call Taxi companies).
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