TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Communication & Navigation Equipment: VHF, UHF, GPS, Satellite phones ETC.
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TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

September 2011:
I have rewritten this section in order to hopefully present a more condensed, easier to follow essay on Radio Communications





TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS:


As a 4x4 owner participating in either local “get-togethers” with others in your area, or even on a weekend trail with a group of friends, one of the more enjoyable accessories is a two-way radio, enabling you to remain in contact with others within your group. This has many advantages: one is warned of any possible road or track dangers well in advance thus enabling you to take the appropriate action in time, or being told of where to find game in a game-drive, or simply to keep in contact with your friends when driving in convoy, thus helping to pass time and staving off boredom when driving along long tarred roads to reach your destination. Of course, it can be regarded as a life-saving tool as well during accidents or breakdowns. There is a lot of confusion over the type of radio to choose, so let’s consider the facts.



LICENSING:

For normal 4x4 use, one is able to join a Club that is affiliated to ORRA (Off Road Radio Association). ORRA has been tasked by the AAWDC (Association of All-Wheel Drive Clubs) to provide country-wide radio licences to its member Clubs and therefore directly to the members of those Clubs. By working through ORRA, the radio user is able to obtain a radio licence essentially in a matter of days, instead of applying directly to ICASA for a private frequency which is a lengthy and expensive process. In this latter case, you will only be granted a radio licence for use within your own immediate geographical area, usually limited to no more than 50km radius of your place of residence. Obtaining your licence through ORRA permits you to use the various frequencies issued by ORRA anywhere within the borders of RSA.


WHAT TYPE OF RADIO DO I CHOOSE - 29MHz AM or VHF/ FM?

Currently, there are two main modes of radio communications available to members of ORRA. The first one comprises the older 29MHz AM type radio, while the newer technology VHF/FM radio is an alternative choice. In days gone by, 29MHz radios were freely available and their pricing was extremely competitive, therefore they were widely used for short-distance communications. As the years passed by however, many Manufacturers of these radios dropped the 29MHz AM models which were uneconomical to manufacture in the relatively small quantities that were sold worldwide and concentrated more on the VHF/FM radios that were selling in considerable quantities world-wide. Following below, a brief description of the two modes of radios.


/contd

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
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Family_Dog
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Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
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Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

29MHz AM RADIOS:

The virtues of 29MHz AM radios are many – they are relatively cheap and many Clubs and 4x4 drivers make use of them. They are priced at around R1100 – R1800 excluding antenna & installation. Their reliable operating range is anything from about three to five kilometres or thereabouts, but this varies greatly with weather conditions and time of day, as well as area of operation and motor vehicle suppression. AM radios are susceptible to engine and atmospheric disturbances, resulting in a crackling sound when such disturbances are present. Adjusting the radio’s squelch control can help eliminate these disturbances but this also has the effect of reducing operating range. The radios are fairly low-power units operating at around 4 – 5 Watts RF.


Antenna location is critical with a 29MHz AM radio and a permanent mount is to be preferred over a magnetic mount. Ideally the antenna should be mounted in the middle of a large expanse of metal, such as the roof of a double-cab. This might not always be convenient, and mounting the antenna elsewhere could result in directional RF radiation. A good compromise would be obtained by mounting the antenna as high as practicable on either the “B” or “C” pillar of a vehicle, ensuring that the steel whip and spring does not come intro contact with any other metal work.

Below are examples of typical 29MHz AM radios available.

Dragon KR-80 AM Radio
Image


GX300 29MHz Radio.
Image



VHF/FM RADIOS:

This type of radio has been professionally in use for many years world-wide and is supported by all Manufacturers of two-way radios. These radios are typically high-powered but in South Africa the power limit is restricted to 25W for Commercial use. This is, however, completely adequate for good radio communications between two or more users.


For our ORRA purposes the radios operate on VHF, which is a range of frequencies within the 146 - 174MHz band. VHF radios offer excellent communication range, anywhere from about 15 - 30Km between mobile units but dependent uponsurrounding terrain. They are powered at 25 watt RF output and are immune to interference caused by atmospheric or electrical conditions. All VHF radios require an appropriate ICASA licence, or, in our case, an ORRA licence.

The same rules for AM antennas apply to the FM antennas as well. However, there are two common types available:

* Quarter Wave Antenna, which should once more be mounted in a central position on a metal surface or on the B or C pillars of a vehicle. The antenna whip is only some 400mm or so in length. This is the currently preferred antenna for ORRA purposes because of the fairly wide spread in the current ORRA frequencies. Quarter-wave antennas are a good choice in hilly terrain.

* 5/8 Antenna, normally, suitable for B or C pillar mounting but can work on a bull bar. This type of antenna will produce good results when used either for a single frequency or a group of frequencies clustered in close proximity to one another. Not suitable for frequencies that are spread far apart from one another.



Pictured below are some typical multi-channel VHF/FM Radios. As ORRA has revised their channel list, we will no longer consider any radio below 8-channel capacity.


KENWOOD TK7100 64-Channel VHF Radio
Image




KIRISUN PT8100 VHF 256-Channel Mobile Radio
Image




VERTEX VX220012 8-Channel VHF Radio
Image



The radios depicted above are all Alpha-Numeric Display models with LCD screens. This is highly advantageous because instead of the customary “Ch 1” being displayed, the radio can br programmed to display “ORRA 1” ORRA 2+T” etc, which certainly makes things a lot easier if you have to select an individual channel from a bank of, say, eight channels.


/cont'd

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
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Prado 3.4 VX
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Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

PORTABLE RADIOS (“HANDHELDS”):

29MHz hand-held portable radios are not being discussed here as they have shortcomings due to their low-frequency operation coupled to a cumbersome antenna. They have a very limited operating range and are also no longer readily available.



i) UHF LICENCE-FREE PORTABLE RADIOS:


The cheapest portable radios are the so-called “Licence Free” hand-held radios, which have very limited RF output stages, usually somewhere between 50mW & 500mW. Dump the 50mW, they are worthless. The 500mW radios offer an operating range of anywhere between 1 – 3Km, depending upon terrain, irrespective of what their Manufacturers might like to claim on the packaging. Line of sight provides the best range. The Stealth ST-200 radio pictured here is supplied is powered by a Lithium-Ion battery pack and is supplied complete with a battery charger. Useful for short-range communication, but with range restrictions of around 1 kilometre maximum when used between two vehicles on an open road. This range can be increased significantly however by means of an external magnetic antenna placed on both vehicles.

This radio operates on various fixed frequencies in the UHF band so therefore is not suitable for the programming of the VHF ORRA frequencies.



ii) VHF PORTABLE RADIOS:

These are the most popular of all types of radios and are used extensively throughout the Country by Industries, Mines, Municipalities etc, so they are certainly rugged enough for the average 4x4 driver! Again, for our purposes, we will not consider portable radios of fewer than 16 channels, which has more or less become the Industry norm in any case. They all have similar ratings of 5 watts RF and 16 channel capability. While portables with many more channels are available, these are not required for our purposes.

Battery life on most portables is rated for a minimum period of eight hours usage during which the radio transmits for 5% of that time, receives for 5% and is on ‘idle’ for the remaining 90%.


Some examples of Popular VHF Portable Radios
Image



cont'd/

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
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Family_Dog
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Joined: 02 May 2009 20:31
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Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
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Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

ORRA LICENCING PROCEDURE:


Licencing your radios through ORRA is quick and easy! As long as you are a member of a Club that in turn is one of the AAWDC member Clubs, you may apply to ORRA for a VHF or 29MHz licence.

Download the form from the ORRA website http://www.aawdc.org.za/fg_orra.asp and fill in the appropriate details. Approach your Club’s Radio Officer and request a letter from him/her confirming your membership of that Club. Pay in the required amount as per the ORRA application Form and submit all three documents to ORRA at the address listed on the Application Form.

Congratulations! You will shortly be joining the thousands of people who have found out the benefits of two-way radio!



More details upon current two-way radios may be obtained by sending an email to repcom @ lantic . net (remove the spaces) and requesting a copy of the 4x4 price list, which is updated on a regular basis.





-F_D

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
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Posts: 163
Joined: 02 May 2009 20:31
Full Name: Eric Skeen
Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

(This page temporarily blank as I've edited the content. Reserved for future additions to content)

Some examples of Mobile Antennas
Image


-F_D

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
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Posts: 163
Joined: 02 May 2009 20:31
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Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

HF/SSB RADIO:

These high-power radios operate on low RF frequencies, typically between 1.8 ~ 30MHz, at RF levels of about 100W. They offer greatly extended operation, but they do have pitfalls. The operating range varies with a local ground-wave signal providing about 30Km radius, but this is in general not too reliable and nor is the radio designed for ground-wave communications. HF comes into its own with the reflected Sky-wave signal, which signal that is reflected off the Earth’s Ionosphere, which is constantly varying in height from above the Earth’s surface. The RF path can be compared to a tennis ball bouncing up and down as it is thrown hard into the ground.

The distances obtained by HF are virtually anything from 300Km upwards but the operating frequency (and therefore operating range) is very much influenced by the height of the Ionosphere at the time of transmission and therefore these radios are generally allowed to operate on three or four frequencies to allow for the changing conditions. Weather conditions play a major part in obtaining clear reception, as the system is essentially an AM one. Atmospherics and Lightning would cause difficult reception, as would electrical impulses.

Because of the need for various operating frequencies, you will have to consider using an “Automatic Antenna Tuner”. Each operating frequency requires the antenna to be a certain fixed length to provide for maximum signal transfer and also to prevent damage to the radio. This is done either by the use of an Automatic Antenna Tuner, or you could carry four stainless steel whips & HF Coils and change them as you change frequency – not too practical!

HF/SSB licences, although obtainable, are fairly restricted due to the limited number of available frequencies. This is not a bad thing in itself, as it is comforting to know that there might be other users on the same frequency should you be stranded in a remote area and in need of assistance. You are allowed to use HF across borders, provided you have the necessary Radio Communications Licence from both Country’s Regulatory Authorities.

Successful HF radio operation requires a learning curve, but for those traveling long distances where there is no other means of communication, it is a blessing.

Pros: Greatly enhanced RF coverage

Cons: Price, adversely affected by bad weather, long antenna/s



KENWOOD TK90 HF/SSB Radio
TK90 HF_SSB.jpg
TK90 HF_SSB.jpg (35.95 KiB) Viewed 23898 times


FT-857D HF/VHF/UHF ALL MODE TRANSCEIVER
FT-857D HF-VHF-UHF ALL MODE TRANSCEIVER.jpg
FT-857D HF-VHF-UHF ALL MODE TRANSCEIVER.jpg (50.31 KiB) Viewed 23898 times

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
Senior Member
Senior Member
Posts: 163
Joined: 02 May 2009 20:31
Full Name: Eric Skeen
Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

(I've left this section in as it applies for people who choose not to go the ORRA route but apply for their own Radio Frequency.)



SECTION TWO:

ICASA LICENCING PROCEEDURE:
All Two radio equipment has to be licensed. In the case of the so-called “Licence-Free” products, ICASA has already approved these short-range radios for use by the general public, School sports events, parking attendants, etc.

As previously mentioned, some of the Clubs have already been allocated an operating licence for their members by ICASA, and should you wish to make use of their frequencies, you will have to contact the Club directly and apply for membership. They will allow you to use their frequencies subject to a small fee to cover their licencing costs. The Licence granted to the Clubs is exactly that: They will allow you to use this frequency as long as you are a member of the Club, but it is not transferable to you should you resign from the Club, and you may not operate any radio without an official licence (ICASA ruling). The fines are not small!

You may also apply for a private radio communications licence, but there is little sense in that if no-one else is on the same frequency as you. It therefore makes sense to join a Club and use their allocated frequency. If you live in a remote area, you may by all means apply for a private communications frequency, or, as already mentioned, form a local Club with other 4x4ers and apply for a frequency in your new Club’s name.

ICASA requests a Radio Communications Licence Application fee must first be paid to them before they will consider your Application. You are required to submit proof of payment along with your Application. They do not accept any form of payment directly at their premises. Currently, the Application Fees are R290 for 29MHz AM Radio, and R620 for VHF, and then if granted, an Annual Licence renewal fee of R42.00 per radio applies. Should you apply in the name of a Club, these Application costs can be shared amongst the members. In the case of a VHF frequency, you will receive a frequency which can be used within a 50Km radius of your home, or Base. You are not legally allowed to make use of the same frequency outside this area, unless you apply for a "Roving Frequency", which is the type of frequency that the larger Clubs would apply for. Roving frequencies require a minimum of 40 radios to be granted such a frequency, and the applicable annual licence fee becomes expensive for an individual.

The following thread is separated as per the requirements on the ICASA Application Form one “reply” per page. There is a degree of repetition, but the Form can be confusing. I am trying to simplify it as far as I reasonably can. Members are invited to PM me for any additional help.

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
Senior Member
Senior Member
Posts: 163
Joined: 02 May 2009 20:31
Full Name: Eric Skeen
Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

OBTAINING THE RADIO COMMUNICATIONS APPLICATION FORM


The "Landmobile Application" form can be downloaded from the ICASA web site ICASA Land Mobile Application Form

Scroll along until you find the application form entitled "Landmobile Application", and then download the PDF document, which will open in a new window. Print it out, it is six pages long. It is advisable to number the pages in the order they are printed so that they do not get muddled
up, they are confusing enough!

-OR-, if this Forum supports downloads, you can scroll along to the PDF uploaded here.

Please use BLACK INK to complete the form. The emphasis here is on a VHF FM frequency, but the procedure is much the same as for 29MHz (or 27MHz CB) AM, with a few small changes where applicable.

Page 1: SECTION 1: RADIOCOMMUNICATION APPLICATION

Under the right hand column, "Type of Service"

Place an X next to "Private", about two-thirds down the page.

Now go to Page 2 (each page is under a separate thread to make for easier reading).

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
Senior Member
Senior Member
Posts: 163
Joined: 02 May 2009 20:31
Full Name: Eric Skeen
Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

Page 2:

APPENDIX A - DETAILS OF FIXED AND MOBILE TERRESTRIAL SERVICE.

Insert your name in the space provided and insert a X in the block corresponding to "Voice".

Purpose of Service: "Roving Frequency for 4X4 use"

Nature of Service: "Roving Frequency for 4X4 use"

Place an X under Simplex.

Name of Operational Area:
(Here you must insert where you intend to mainly use the Service. You are generally limited to a 30-50Km radius of a specific area. However, for a Roving frequency, just enter "Roving VHF Frequency RSA").

Proceed to Page 3.

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
User avatar
Family_Dog
Senior Member
Senior Member
Posts: 163
Joined: 02 May 2009 20:31
Full Name: Eric Skeen
Nickname: F_D
Home Town: Klerksdorp
Current 4x4: Hilux 2.7i IFS D/C
Hilux 2.2i SFA D/C
Prado 3.4 VX
Home Language: I try to be Fifty/Vyftig
Been thanked: 19 times
Contact:

Re: TWO-WAY RADIO CONSIDERATIONS FOR 4X4 DRIVERS

Post by Family_Dog »

APPENDIX A: DETAILS OF FIXED & MOBILE TERRESTRIAL SERVICE

Under NETWORK LAYOUT, fill in the following:

Modulation Scheme:
F3E (for VHF FM), or
A3 = 29 MHz AM
A3J = LSB / USB (i.e. A Sideband capable CB).


Service Area / Radius in Km: 30Km
(It is futile applying for 50Km, UNLESS you plan to make use of a BASE STATION in addition to a MOBILE RADIO).

SITE A:

Pages 3 & 4 are duplicated, one page would be required for any FIXED UNIT, and the other for MOBILE UNITS, i.e. those fitted to the vehicles.

FIXED UNITS:
Unless you plan to make use of a Base Station (i.e. a FIXED unit at your home, place of Business, etc, leave this section blank)

MOBILE UNITS:

Fill in details under
CONTACT PERSON

TELEPHONE

EQUIPMENT MANUFACTURER & BRAND NAME (Found on the Radio or packaging)

MODEL No. (Found on the Radio or packaging)

TRANSMITTING POWER (25W) (or 5W for 29MHz AM)

ERP
(25W)

TYPE OF TONE CODING
CTCSS

ANTENNA MANUFACTURER
WEBB

ANTENNA GAIN
0 (Tx & Rx)

POLARISATION
Vertical

ANTENNA TYPE & MODEL:

ZARA 130 for VHF,(...OR:...ZARA 29 for 29MHz AM / ZARA 27 for 27MHz CB)

FREQUENCIES REQUIRED:
(146-174MHz) (or 29MHz / 27MHz CB)

COUPLING LOSS - Tx & Rx: 0 dB

EQUIPMENT TYPE APPROVED BY ICASA:
YES
(All radios type approved by ICASA will have a little ICASA sticker attached to the radio as well as the packaging.


Proceed to the next section.

White Fang: 1999 2.7i DC Raider 4x4
Bull Dog: 1987 4Y-EFI 2.2 DC 4x4
Pra Dog: 1998 Prado VX 3.4
Hound Dog: 2000 2.7i SC 4x4

One Staffie, One Jack Russell, One Ring Neck Screecher, One Gold Fish
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