Buying an HF and getting the most out of it
Buying an HF and getting the most out of it
(c) D Kerr 2005
Please note that this article is now six years old. ICOM have advised me that they now have a type-approved solution for Australia.
"Just a quick note to say I ran across your HF Marine radio run-down on the web and found it well written, but some of the information is out of date. In particular, it does not mention the Icom IC-M801E, which is a fully type approved option for people requiring a Class E marine HF.
Last month we looked at Australian HF facilities for Bluewater Cruising (and explained some of the acronyms). If you currently have a good HF radio and use Penta Comstat, Russell Radio (NZ) or similar, then it's unlikely you'll replace that radio yet.
What I tested
I tested Icom's IC-M802, the Barrett 980E and the JRC JSB-196. Although the JRC is intended for larger vessels, I tested it because it is relatively compact and could be installed in a yacht.
Add-ons or upgrades
Some cruisers responded to our survey saying that they had purchased an ICOM IC-M710 having been assured that they could add DSC later. This is true, but the cost would be high.
Very stringent frequency stability requirements and low sales volumes are the main reasons that "add on" DSC units have not been commercially produced for older HF radios. As I concluded last month, it no longer makes sense to purchase a new non-DSC radio.
What cruisers said in our survey
Not many cruisers have invested in a DSC capable radio. There were complaints about the need for a second DSC Watch antenna and the quality of Icom's manual. Barrett owners complained about insufficient channels, dealer-only transmit frequency programming and "return to scan" problems with weatherfax and other standby operation. One reader asked why microphones connect on the front panel where flexing and knocking can fracture the cable. I agree, but unfortunately all modern radios including Ham radios tend to use a front mount connector.
GMDSS Standards
There are two relevant GMDSS standards for DSC radios. "Class A" is a full blown specification for large commercial vessels. A revamped "Class E" specification is for recreational vessels. Cruisers would not like the size or price tags on many "Class A" units.
I could only find two Class E HF radios being sold anywhere, including Australia. These are Icom's IC- M802 and the Barrett 980E. There are considerable differences between them, though both conform to the specification. The IC-M802 is a fuller featured unit which costs more and is not "type-approved" for installation and operation in Australia. Icom and its resellers clearly mark the radio "For Export Only" but despite that, some radios are being installed locally. The 980E is Australian type-approved; it has been designed to a lower price-point and has some limitations which could be a little frustrating.
The JRC JSB-196GM is a "Class A" unit which is approved in Australia and could be fitted to a yacht. However it is substantially more expensive than the Barrett 980E or ICOM IC-M802.
What's wrong with the standard?
The Class-E specification appears to have been written by non-sailors. It assumes yachts have HF radios on full time so that the DSC channels can be monitored . This does not happen because of the high power drain. Realistically, a blue water cruiser will turn the radio on for skeds, email or distress call and it will be off the rest of the time. As a result, the continual scanning of DSC channels is meaningless.
To conform to the Standard, Icom and JRC have equipped their units with a dedicated DSC-only receiver and this requires a second antenna. Barrett uses the main transmit/receive antenna and switches the receiver to scan DSC channels after a relatively short time. This means that you can be several minutes into receiving a weather fax on the Barrett when the receiver switches off and onto DSC scan (effectively ruining the weather fax). You CAN disable this behaviour, but only until the set is powered off. Don't blame Barrett for this unfriendly behaviour- it's the fault of the standard.
Type Approval- what the ACA says
I contacted the ACA (Australian Communications Authority) about the issue of type approval. I received very detailed responses from them. Here is a synopsis of the rules and what they said:
1. Radios sold for use in Australia are required to have an approval label. This looks like a tick mark and you will find a similar label on all sorts of electronic equipment.
2. ACA does NOT keep a list of type approved radios! They leave it up to the importers and resellers to comply.
3. It is an offence to even turn on a non type approved radio, UNLESS it is for the purpose of summoning help in a serious situation. The penalties for "improper use" range from $13,200 for an individual up to $165,000.
The Australian type approval is based on the European standards. For this reason, the IC-M802 is type approved in the US but not Australia or Europe. Barrett has expended considerable effort and cost to ensure type approval on all three continents.
From Icom
Icom is not seeking type approval for the IC-M802 in Australia because of the high cost and the likelihood that the radio would not conform. The main issue is that transmit frequencies can easily be set from the front panel, even though these are within the marine bands. I find this standard incredible and think that Australia should adopt the more pragmatic US model.
Legally
The only Class-E radio you can legally install and operate in Australia is the Barrett. The JRC is also a legal option if you can afford it.
My tests
I tested each radio on the work bench in order to provide a direct technical comparison. Each was "stressed" by using it in continuous data mode for over an hour and units were also deliberately operated with an untuned antenna to simulate tuner failure or a poor set-up on a boat. I also used the radios "on air" with voice traffic, email and DSC. Each radio was tested for one week.
I looked at transmit performance with low battery voltages which are a common occurrence on cruising boats. In general, the radios performed well but adequate power connections are essential (see the tips section).
ICOM IC-M802
This transceiver comes with a compact control head and separate main power unit which can be installed out of sight. Installation was relatively simple though you must supply your own tuner cables. As with the Barrett, the tuner lid needs to be removed to install the cables. I thought the tuner plug on the radio was flimsy. I foresee reliability problems if the cable is not well supported.
Despite the rather negative comments from one reader, I found the manual adequate though it was unclear about the watch antenna and non-distress DSC calls. A separate receiver antenna is required for the DSC Watch receiver (as is the case for all DSC transceivers except the Barrett). This second antenna could be an insulated leg of a bridal back stay. Length needs to be about four metres or more. Do not run it strapped to the main antenna feeder as I saw on one boat or you will blow up the DSC-Watch receiver!
Received DSC calls were hard to ignore as they triggered a loud siren- similar to a car alarm. Sending of distress calls was quick, simple and menu driven. 100 MMSIs can be pre-programmed with understandable names to make non-emergency contact easy.
The large display is excellent. Unlike the other radioss, the protected distress button is not illuminated. The microphone is good with channel control and user programmable buttons. The radio puts out at least the rated power, sometimes a little more. "Real world" tests to other boats and Penta Comstat went well.
The IC-M802 has a crystal oven that is on even when the radio is turned off in order to meet the stringent frequency stability requirements. This means that the radio will use about three amp hours per day unless you disable it with a separate power switch or circuit breaker.
Barrett 980E
The 980E comes packaged in one compact unit. An optional control head is available if required but was not tested. Installation was simple with all required bits and pieces supplied. A laminated "how to" card is supplied for making DSC distress calls. The installation section of the manual was excellent. The supplied power cable was too long/thin, resulting in more than 0.7volts drop along the cable when sending a DSC distress call. The healthy 12.65V at the battery was 11.9 by the time it reached the Barrett (when transmitting). If you buy one, cut off most of the cable and install heavier cable.
Setting up the DSC was relatively straightforward. The manual was slightly better than the IC-M802's in this regard, but the small display and lack of a rotary knob made programming more tedious. You cannot program as much as on the IC-M802. The DSC is adequate but would be a bit of a pain if you were frequently using DSC for other than distress calls (e.g. AUSREP reports or calling other vessels). I felt frustrated by the inability to program my own transmit frequencies and there are barely sufficient channels. Indeed, if you were on a world circumnavigation needing voice, email and weatherfax, you would have to plan very carefully indeed or have dealers re-program the radio in selected countries. Operation within a more restricted area such as the Pacific would be fine.
The Barrett has some good self-diagnosis features and can measure a number of internal parameters which are useful for diagnosing problems.
I was caught out by the "return to scan" issue a couple of times when I was listening to weather forecasts and skeds. An email to Barrett got a quick response on how to temporarily turn it off. I was impressed by Barrett's responsiveness each time I contacted them with an issue or a question.
All tests went smoothly. The emergency button is separate from the main unit, is lit all the time the radio is on and can be mounted in a strategic spot. Sending a distress call was a little slower than on the IC-M802, but still quick. The 2*16 line display and five leds on the Barrett are fully utilised and need to be improved on future models. There is no signal strength meter though you can see power output and mistuning information. There is programmable scanning which is adequate but not as good as the other radios. An internal GPS, internal scrambler and various mounting schemes are useful optional extras.
JRC 196GM
I tested the basic transceiver and tuner but not the DSC unit. I liked the very large display and ease of use of the controls. The DSC unit is the same size as this compact transceiver so you could definitely fit them onto a yacht. The microphone is basic with no extra controls. Of the three manufacturers, JRC did the best job in providing all screws, brackets, cables etc.
The manual has plenty of typos and is the poorest of the three. Despite that, it is usable. There are plenty of user programmable channels, organised in 10 groups of 20 each with useful text aliases for quick recognition.
The DSC-ready transceiver is similar to the one I tested, but has tighter specifications on frequency stability. The unit I tested did not have a "type approval" sticker on it and I was also able to program my own transmit frequencies. I am assuming that the DSC-capable radio may not have this programmability.
I found that TMQ, the agents, were helpful but not as knowledgeable as Barrett or Icom.
This radio had excellent power output, good reception, a fine tuner and good ease of use. It did not seem to be rated for continuous data, but it comfortably passed my "torture test" with full power on data transmission. It also comfortably handled severely mistuned antennas. As with the IC-M802, I liked the transmit power indication and receiver signal strength meter. An attenuator is a handy feature when other nearby stations are blasting away at high power.
Performance of this radio at low battery voltage was excellent. In my tests, the power output only dropped 10% between 13.6V and 11.6V.
Summary
All units are solidly built and should give you many years of trouble free operation on voice, email and DSC. It IS important to understand radios AND have a thorough knowledge of DSC if you are going to install them yourself. The antenna tuners are similar and perform well.
The IC-M802 comes out top in overall price/performance and ease of use. This radio would be my choice if I did not have to worry about type approval. DSC facilities are easy to set up, programmability is good and performance is excellent.
If type approval is necessary, then the Barrett is the way to go. It is simplest, cheapest and smallest/lightest. You will find some annoyances with the small, limited display screen, the shortage of channels, return-to-scan function and the need to have a dealer program your transmit frequencies. Most of these annoyances result from the GMDSS specification and type approval regulations. I hope that Barrett improves internal memory and the display in their next model.
If money is no object and you need a type approved radio, then the JRC is worthy of consideration. It is solid and well built (but heavy), relatively easy to operate with a large display. Being a Class-A unit, it has the most DSC capability of the radios tested.
The best from your HF
Typically, you have spent a lot of money on your radio and want to get the best from it. I have noted some typical problems experienced by cruisers and the following should be of some assistance. If it seems like gobbledegook, then it might be worthwhile consulting a knowledgeable marine radio technician to perform a mini-survey.
Poor quality
We often hear poor transmissions caused by low battery voltage. Some radios are provided with inadequately sized power wiring so that 12.6 volts at the battery can end up being more like 10.5 volts at your radio- a recipe for poor performance. As a guide, for 3 metres distance between batteries and the radio, you need cable with each internal wire 3.5mm in diameter. You must scale up the diameter 1.4 times each time you double the power cable length.
Tuner
Nearly every boat will have an antenna tuner which matches the particular chosen frequency of the radio to the length of the antenna. It's similar to the gearbox in your car, matching the engine to the wheels. Your tuner MUST be as close to the antenna as possible- ideally four metres or less.
Feeder wire
Many people take the wire from the antenna tuner to the backstay and simply clip the intervening length to the uninsulated lower part of the backstay. This is BAD for several reasons. Firstly, what is known as the "capacitance" of this connection is very important to the tuner's ability to function properly. Secondly, there can be several thousand volts on this wire and you could get sparking through the insulation. So, employ spacers of about 25mm or more between the feeder wire and any other metallic object. Mine are made from pieces of nylon cutting board and show no deterioration after six years. Recently, we manufactured spacers for a boat in Fiji. A piece of 12mm conduit was procured from the local dump and cut into 70mm lengths. Grooves were filed in each end, holes drilled and they were then whipped to the backstay and feeder. Cheap but good! Make sure you use proper feeder wire which is characterised by lots of fine wires, preferably tinned, with high voltage insulation that can take at least 1000 volts and is uV resistant.
Grounding
Most people are aware of the antenna on their boat. This is often an insulated backstay. Less well known is that the backstay is only half the transmission system. The other part is the "ground" or connection to the ocean. You need a good connection using 50mm copper strip or a short, heavy cable with many fine wires (at least 12mm thick),. These run from the tuner to a metallic fitting in contact with seawater or at least 1 square metre of metal sheet against the inside of the hull and below the waterline. This subject is a big one and we don't have enough space to cover it adequately. Steel boats are relatively simple, but you still have to ensure corrosion does not spoil your contacts.
Electrolysis
I almost ruined my Saildrive by connecting the engine block to the keel. It provided a reasonably earth for the tuner, but the electrolysis after 12 weeks was dreadful. You can fix this sort of problem using a capacitor- a device that passes HF but blocks the harmful DC currents. You can make your own by buying 10 "0.1 microfarad disc ceramic capacitors" from somewhere like Dick Smith and soldering them in parallel. Place in a 35mm film canister and fill it full of Epoxy. You can now use this to safely link metal fittings that are in contact with seawater.
Coaxial cable
The cable that connects the radio to the antenna tuner can be reasonably long, but you must use the correct sort of cable which is "50 ohm coaxial cable". However this comes in a variety of diameters. Note that "75 ohm cable" used for TV installations mustn't be used! You can use 5mm diameter cable (RG-58U) up to a maximum of about 10 metres which will lose 25% of your power. Beyond that length, you need RG-213U cable which is approximately 10mm in diameter but has only a quarter of the loss of RG-58U. Failure to use the correct cable will cause a loss of transmitter power.
Good luck!
It has not been possible to cover everything in the two articles, so if you have further questions I would be happy to answer them through the editor.
BOX 1: General
ICOM IC-M802 Barrett 980E JRC 196GM
Power output claimed 150W 100W 150W (100W <4Mhz)
With voltage input 11.6-15.6V 13.6V 12.3-15.0V
Measured power @ 12.6V # 135-180W 85-100W 105-157W
Low power setting 60/20W 25W 50W
Current drain standby 1.9Amps 1.5Amps 2.57Amps
Current drain full power 30Amps 18Amps 35Amps
Current drain when "off" 0.11Amps 0Amps 0.01Amps
Receiver sensitivity Best V. Good V. Good
User manual 70% 80% 60%
Overall ease of use 90% 80% 85%
GPS NMEA 183/3.01 183 183
Channels 1355 450 1893
Including user channels 160 450 200
Tuner * AT140/130/120 911 NFC196
Remote control Yes Yes Yes
Antennas required 2 1 2
Customer Service Excellent Excellent Good
* The Barrett comes with a re-badged SGC tuner. The IC-M802 was tested with an AT130 but can be used with several tuners. I liked the JRC tuner which was pre-wired, sealed, with a drain tube but can only be mounted one way if exposed to the elements.
# Measured power usually varied with frequency. The power into a "perfect" dummy load was lowest for IC-M802 and 980E at high frequencies with the highest power at lower frequencies. JRC was lower (as per their specification) at lower frequencies. All units have adequate power output.
BOX 2: DSC
ICOM IC-M802 Barrett 980E JRC 196GM
Sending quick MAYDAY 6.5secs 6.5secs N/A
Sending full MAYDAY 25secs 31secs N/A
Power output MAYDAY 128W 95W N/A
BOX 3: Physical & Cost
ICOM IC-M802 Barrett 980E JRC 196GM
Weight (DSC Radio) 6Kg 5Kg 12.3Kg incl DSC
Weight (Tuner) 2Kg 2.5Kg 3.4Kg
Radio volume # 8,296 5,040 14,500 incl DSC
Tuner volume # 6,256 7,481 5,589
Warranty 2 years 3 years 2 years
RRP incl. GST * $5,002.80 (w/AT130) $4,290.00 $10,000
# The volume of each unit in cubic centimetres. You can get dimensions from brochures or the web.
* Prices were correct at the time of going to press.
BOX 4: For the techos
Test equipment used:
Rohde & Swartz Sweep Generator
Digital meter with data acquisition software
Function Generator
Dummy loads
Power and SWR meter
100Mhz Oscilloscope
Variable power supply and battery banks
Fixed length dipole
Backstay antenna
PICS
Slides
HF1 Lead photo. "Good HF installation is essential"
HF2 IC-M802 (left) and 980E (right) under test
HF3 Barrett 980E- compact, cheapest & Type Approved
HF4 ICOM IC-M802- Best features but not Type Approved
HF6 Remote heads make for neat installations (IC-M802 shown)
HF7 Feeder standoffs using12mm conduit
HF8 Feeder standoff using nylon breadboard
HF9 Icom and Barrett tuners must be opened to install cables
Electronic
HF10.JPG 196GM display is excellent
HF11.JPG IC-M802 display is excellent
HF12.JPG Barrett's display is small and basic
HF13.JPG Use capacitors to isolate DC electrolysis
HF14.JPG Barrett documentation manual was best
HF15.JPG Use the thick RG-213U cable with a good connector (right one is best)
Author
David Kerr is a regular contributor who has a keen interest in Radio, Electronics and Sailing.
The article appears to be crosslinked to by a non-ICOM-authorised importer of the M802 who is selling the radio to customers who risk fines if they install and use the radio here.
If it were possible to update your article to indicate that there's a fully legal Icom option, it would be appreciated!"
Are you in the market for a new HF radio? David Kerr tested and evaluated DSC equipped radios from the few which he found suitable for cruisers. He also provides some useful tips about HF installation.Last month we looked at Australian HF facilities for Bluewater Cruising (and explained some of the acronyms). If you currently have a good HF radio and use Penta Comstat, Russell Radio (NZ) or similar, then it's unlikely you'll replace that radio yet.
What I tested
I tested Icom's IC-M802, the Barrett 980E and the JRC JSB-196. Although the JRC is intended for larger vessels, I tested it because it is relatively compact and could be installed in a yacht.
Add-ons or upgrades
Some cruisers responded to our survey saying that they had purchased an ICOM IC-M710 having been assured that they could add DSC later. This is true, but the cost would be high.
Very stringent frequency stability requirements and low sales volumes are the main reasons that "add on" DSC units have not been commercially produced for older HF radios. As I concluded last month, it no longer makes sense to purchase a new non-DSC radio.
What cruisers said in our survey
Not many cruisers have invested in a DSC capable radio. There were complaints about the need for a second DSC Watch antenna and the quality of Icom's manual. Barrett owners complained about insufficient channels, dealer-only transmit frequency programming and "return to scan" problems with weatherfax and other standby operation. One reader asked why microphones connect on the front panel where flexing and knocking can fracture the cable. I agree, but unfortunately all modern radios including Ham radios tend to use a front mount connector.
GMDSS Standards
There are two relevant GMDSS standards for DSC radios. "Class A" is a full blown specification for large commercial vessels. A revamped "Class E" specification is for recreational vessels. Cruisers would not like the size or price tags on many "Class A" units.
I could only find two Class E HF radios being sold anywhere, including Australia. These are Icom's IC- M802 and the Barrett 980E. There are considerable differences between them, though both conform to the specification. The IC-M802 is a fuller featured unit which costs more and is not "type-approved" for installation and operation in Australia. Icom and its resellers clearly mark the radio "For Export Only" but despite that, some radios are being installed locally. The 980E is Australian type-approved; it has been designed to a lower price-point and has some limitations which could be a little frustrating.
The JRC JSB-196GM is a "Class A" unit which is approved in Australia and could be fitted to a yacht. However it is substantially more expensive than the Barrett 980E or ICOM IC-M802.
What's wrong with the standard?
The Class-E specification appears to have been written by non-sailors. It assumes yachts have HF radios on full time so that the DSC channels can be monitored . This does not happen because of the high power drain. Realistically, a blue water cruiser will turn the radio on for skeds, email or distress call and it will be off the rest of the time. As a result, the continual scanning of DSC channels is meaningless.
To conform to the Standard, Icom and JRC have equipped their units with a dedicated DSC-only receiver and this requires a second antenna. Barrett uses the main transmit/receive antenna and switches the receiver to scan DSC channels after a relatively short time. This means that you can be several minutes into receiving a weather fax on the Barrett when the receiver switches off and onto DSC scan (effectively ruining the weather fax). You CAN disable this behaviour, but only until the set is powered off. Don't blame Barrett for this unfriendly behaviour- it's the fault of the standard.
Type Approval- what the ACA says
I contacted the ACA (Australian Communications Authority) about the issue of type approval. I received very detailed responses from them. Here is a synopsis of the rules and what they said:
1. Radios sold for use in Australia are required to have an approval label. This looks like a tick mark and you will find a similar label on all sorts of electronic equipment.
2. ACA does NOT keep a list of type approved radios! They leave it up to the importers and resellers to comply.
3. It is an offence to even turn on a non type approved radio, UNLESS it is for the purpose of summoning help in a serious situation. The penalties for "improper use" range from $13,200 for an individual up to $165,000.
The Australian type approval is based on the European standards. For this reason, the IC-M802 is type approved in the US but not Australia or Europe. Barrett has expended considerable effort and cost to ensure type approval on all three continents.
From Icom
Icom is not seeking type approval for the IC-M802 in Australia because of the high cost and the likelihood that the radio would not conform. The main issue is that transmit frequencies can easily be set from the front panel, even though these are within the marine bands. I find this standard incredible and think that Australia should adopt the more pragmatic US model.
Legally
The only Class-E radio you can legally install and operate in Australia is the Barrett. The JRC is also a legal option if you can afford it.
My tests
I tested each radio on the work bench in order to provide a direct technical comparison. Each was "stressed" by using it in continuous data mode for over an hour and units were also deliberately operated with an untuned antenna to simulate tuner failure or a poor set-up on a boat. I also used the radios "on air" with voice traffic, email and DSC. Each radio was tested for one week.
I looked at transmit performance with low battery voltages which are a common occurrence on cruising boats. In general, the radios performed well but adequate power connections are essential (see the tips section).
ICOM IC-M802
This transceiver comes with a compact control head and separate main power unit which can be installed out of sight. Installation was relatively simple though you must supply your own tuner cables. As with the Barrett, the tuner lid needs to be removed to install the cables. I thought the tuner plug on the radio was flimsy. I foresee reliability problems if the cable is not well supported.
Despite the rather negative comments from one reader, I found the manual adequate though it was unclear about the watch antenna and non-distress DSC calls. A separate receiver antenna is required for the DSC Watch receiver (as is the case for all DSC transceivers except the Barrett). This second antenna could be an insulated leg of a bridal back stay. Length needs to be about four metres or more. Do not run it strapped to the main antenna feeder as I saw on one boat or you will blow up the DSC-Watch receiver!
Received DSC calls were hard to ignore as they triggered a loud siren- similar to a car alarm. Sending of distress calls was quick, simple and menu driven. 100 MMSIs can be pre-programmed with understandable names to make non-emergency contact easy.
The large display is excellent. Unlike the other radioss, the protected distress button is not illuminated. The microphone is good with channel control and user programmable buttons. The radio puts out at least the rated power, sometimes a little more. "Real world" tests to other boats and Penta Comstat went well.
The IC-M802 has a crystal oven that is on even when the radio is turned off in order to meet the stringent frequency stability requirements. This means that the radio will use about three amp hours per day unless you disable it with a separate power switch or circuit breaker.
Barrett 980E
The 980E comes packaged in one compact unit. An optional control head is available if required but was not tested. Installation was simple with all required bits and pieces supplied. A laminated "how to" card is supplied for making DSC distress calls. The installation section of the manual was excellent. The supplied power cable was too long/thin, resulting in more than 0.7volts drop along the cable when sending a DSC distress call. The healthy 12.65V at the battery was 11.9 by the time it reached the Barrett (when transmitting). If you buy one, cut off most of the cable and install heavier cable.
Setting up the DSC was relatively straightforward. The manual was slightly better than the IC-M802's in this regard, but the small display and lack of a rotary knob made programming more tedious. You cannot program as much as on the IC-M802. The DSC is adequate but would be a bit of a pain if you were frequently using DSC for other than distress calls (e.g. AUSREP reports or calling other vessels). I felt frustrated by the inability to program my own transmit frequencies and there are barely sufficient channels. Indeed, if you were on a world circumnavigation needing voice, email and weatherfax, you would have to plan very carefully indeed or have dealers re-program the radio in selected countries. Operation within a more restricted area such as the Pacific would be fine.
The Barrett has some good self-diagnosis features and can measure a number of internal parameters which are useful for diagnosing problems.
I was caught out by the "return to scan" issue a couple of times when I was listening to weather forecasts and skeds. An email to Barrett got a quick response on how to temporarily turn it off. I was impressed by Barrett's responsiveness each time I contacted them with an issue or a question.
All tests went smoothly. The emergency button is separate from the main unit, is lit all the time the radio is on and can be mounted in a strategic spot. Sending a distress call was a little slower than on the IC-M802, but still quick. The 2*16 line display and five leds on the Barrett are fully utilised and need to be improved on future models. There is no signal strength meter though you can see power output and mistuning information. There is programmable scanning which is adequate but not as good as the other radios. An internal GPS, internal scrambler and various mounting schemes are useful optional extras.
JRC 196GM
I tested the basic transceiver and tuner but not the DSC unit. I liked the very large display and ease of use of the controls. The DSC unit is the same size as this compact transceiver so you could definitely fit them onto a yacht. The microphone is basic with no extra controls. Of the three manufacturers, JRC did the best job in providing all screws, brackets, cables etc.
The manual has plenty of typos and is the poorest of the three. Despite that, it is usable. There are plenty of user programmable channels, organised in 10 groups of 20 each with useful text aliases for quick recognition.
The DSC-ready transceiver is similar to the one I tested, but has tighter specifications on frequency stability. The unit I tested did not have a "type approval" sticker on it and I was also able to program my own transmit frequencies. I am assuming that the DSC-capable radio may not have this programmability.
I found that TMQ, the agents, were helpful but not as knowledgeable as Barrett or Icom.
This radio had excellent power output, good reception, a fine tuner and good ease of use. It did not seem to be rated for continuous data, but it comfortably passed my "torture test" with full power on data transmission. It also comfortably handled severely mistuned antennas. As with the IC-M802, I liked the transmit power indication and receiver signal strength meter. An attenuator is a handy feature when other nearby stations are blasting away at high power.
Performance of this radio at low battery voltage was excellent. In my tests, the power output only dropped 10% between 13.6V and 11.6V.
Summary
All units are solidly built and should give you many years of trouble free operation on voice, email and DSC. It IS important to understand radios AND have a thorough knowledge of DSC if you are going to install them yourself. The antenna tuners are similar and perform well.
The IC-M802 comes out top in overall price/performance and ease of use. This radio would be my choice if I did not have to worry about type approval. DSC facilities are easy to set up, programmability is good and performance is excellent.
If type approval is necessary, then the Barrett is the way to go. It is simplest, cheapest and smallest/lightest. You will find some annoyances with the small, limited display screen, the shortage of channels, return-to-scan function and the need to have a dealer program your transmit frequencies. Most of these annoyances result from the GMDSS specification and type approval regulations. I hope that Barrett improves internal memory and the display in their next model.
If money is no object and you need a type approved radio, then the JRC is worthy of consideration. It is solid and well built (but heavy), relatively easy to operate with a large display. Being a Class-A unit, it has the most DSC capability of the radios tested.
The best from your HF
Typically, you have spent a lot of money on your radio and want to get the best from it. I have noted some typical problems experienced by cruisers and the following should be of some assistance. If it seems like gobbledegook, then it might be worthwhile consulting a knowledgeable marine radio technician to perform a mini-survey.
Poor quality
We often hear poor transmissions caused by low battery voltage. Some radios are provided with inadequately sized power wiring so that 12.6 volts at the battery can end up being more like 10.5 volts at your radio- a recipe for poor performance. As a guide, for 3 metres distance between batteries and the radio, you need cable with each internal wire 3.5mm in diameter. You must scale up the diameter 1.4 times each time you double the power cable length.
Tuner
Nearly every boat will have an antenna tuner which matches the particular chosen frequency of the radio to the length of the antenna. It's similar to the gearbox in your car, matching the engine to the wheels. Your tuner MUST be as close to the antenna as possible- ideally four metres or less.
Feeder wire
Many people take the wire from the antenna tuner to the backstay and simply clip the intervening length to the uninsulated lower part of the backstay. This is BAD for several reasons. Firstly, what is known as the "capacitance" of this connection is very important to the tuner's ability to function properly. Secondly, there can be several thousand volts on this wire and you could get sparking through the insulation. So, employ spacers of about 25mm or more between the feeder wire and any other metallic object. Mine are made from pieces of nylon cutting board and show no deterioration after six years. Recently, we manufactured spacers for a boat in Fiji. A piece of 12mm conduit was procured from the local dump and cut into 70mm lengths. Grooves were filed in each end, holes drilled and they were then whipped to the backstay and feeder. Cheap but good! Make sure you use proper feeder wire which is characterised by lots of fine wires, preferably tinned, with high voltage insulation that can take at least 1000 volts and is uV resistant.
Grounding
Most people are aware of the antenna on their boat. This is often an insulated backstay. Less well known is that the backstay is only half the transmission system. The other part is the "ground" or connection to the ocean. You need a good connection using 50mm copper strip or a short, heavy cable with many fine wires (at least 12mm thick),. These run from the tuner to a metallic fitting in contact with seawater or at least 1 square metre of metal sheet against the inside of the hull and below the waterline. This subject is a big one and we don't have enough space to cover it adequately. Steel boats are relatively simple, but you still have to ensure corrosion does not spoil your contacts.
Electrolysis
I almost ruined my Saildrive by connecting the engine block to the keel. It provided a reasonably earth for the tuner, but the electrolysis after 12 weeks was dreadful. You can fix this sort of problem using a capacitor- a device that passes HF but blocks the harmful DC currents. You can make your own by buying 10 "0.1 microfarad disc ceramic capacitors" from somewhere like Dick Smith and soldering them in parallel. Place in a 35mm film canister and fill it full of Epoxy. You can now use this to safely link metal fittings that are in contact with seawater.
Coaxial cable
The cable that connects the radio to the antenna tuner can be reasonably long, but you must use the correct sort of cable which is "50 ohm coaxial cable". However this comes in a variety of diameters. Note that "75 ohm cable" used for TV installations mustn't be used! You can use 5mm diameter cable (RG-58U) up to a maximum of about 10 metres which will lose 25% of your power. Beyond that length, you need RG-213U cable which is approximately 10mm in diameter but has only a quarter of the loss of RG-58U. Failure to use the correct cable will cause a loss of transmitter power.
Good luck!
It has not been possible to cover everything in the two articles, so if you have further questions I would be happy to answer them through the editor.
BOX 1: General
ICOM IC-M802 Barrett 980E JRC 196GM
Power output claimed 150W 100W 150W (100W <4Mhz)
With voltage input 11.6-15.6V 13.6V 12.3-15.0V
Measured power @ 12.6V # 135-180W 85-100W 105-157W
Low power setting 60/20W 25W 50W
Current drain standby 1.9Amps 1.5Amps 2.57Amps
Current drain full power 30Amps 18Amps 35Amps
Current drain when "off" 0.11Amps 0Amps 0.01Amps
Receiver sensitivity Best V. Good V. Good
User manual 70% 80% 60%
Overall ease of use 90% 80% 85%
GPS NMEA 183/3.01 183 183
Channels 1355 450 1893
Including user channels 160 450 200
Tuner * AT140/130/120 911 NFC196
Remote control Yes Yes Yes
Antennas required 2 1 2
Customer Service Excellent Excellent Good
* The Barrett comes with a re-badged SGC tuner. The IC-M802 was tested with an AT130 but can be used with several tuners. I liked the JRC tuner which was pre-wired, sealed, with a drain tube but can only be mounted one way if exposed to the elements.
# Measured power usually varied with frequency. The power into a "perfect" dummy load was lowest for IC-M802 and 980E at high frequencies with the highest power at lower frequencies. JRC was lower (as per their specification) at lower frequencies. All units have adequate power output.
BOX 2: DSC
ICOM IC-M802 Barrett 980E JRC 196GM
Sending quick MAYDAY 6.5secs 6.5secs N/A
Sending full MAYDAY 25secs 31secs N/A
Power output MAYDAY 128W 95W N/A
BOX 3: Physical & Cost
ICOM IC-M802 Barrett 980E JRC 196GM
Weight (DSC Radio) 6Kg 5Kg 12.3Kg incl DSC
Weight (Tuner) 2Kg 2.5Kg 3.4Kg
Radio volume # 8,296 5,040 14,500 incl DSC
Tuner volume # 6,256 7,481 5,589
Warranty 2 years 3 years 2 years
RRP incl. GST * $5,002.80 (w/AT130) $4,290.00 $10,000
# The volume of each unit in cubic centimetres. You can get dimensions from brochures or the web.
* Prices were correct at the time of going to press.
BOX 4: For the techos
Test equipment used:
Rohde & Swartz Sweep Generator
Digital meter with data acquisition software
Function Generator
Dummy loads
Power and SWR meter
100Mhz Oscilloscope
Variable power supply and battery banks
Fixed length dipole
Backstay antenna
PICS
Slides
HF1 Lead photo. "Good HF installation is essential"
HF2 IC-M802 (left) and 980E (right) under test
HF3 Barrett 980E- compact, cheapest & Type Approved
HF4 ICOM IC-M802- Best features but not Type Approved
HF6 Remote heads make for neat installations (IC-M802 shown)
HF7 Feeder standoffs using12mm conduit
HF8 Feeder standoff using nylon breadboard
HF9 Icom and Barrett tuners must be opened to install cables
Electronic
HF10.JPG 196GM display is excellent
HF11.JPG IC-M802 display is excellent
HF12.JPG Barrett's display is small and basic
HF13.JPG Use capacitors to isolate DC electrolysis
HF14.JPG Barrett documentation manual was best
HF15.JPG Use the thick RG-213U cable with a good connector (right one is best)
Author
David Kerr is a regular contributor who has a keen interest in Radio, Electronics and Sailing.
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