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Simoco SRM9000 Rebroadcast Manual
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Simoco SRM9000 Rebroadcast Manual

Based radio rebroadcast & repeater devices
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Download this manual See also: Service Manual
MRMap - www.mrmap.org.uk
MRMap-GPS-Tracking-Communications-Safety-Mountain Rescue-Mapping-Downloads-Free Software
Rebroadcast Manual
Simoco SRM9000-Based Radio Rebroadcast
& Repeater Devices.
Collated By The LDSAMRA Communications Sub Committee
On behalf of the contributing teams of the North West of
England and Southern Scotland.
Rev C 14 January 2009
MRMap Development Team 14/01/2009

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Summary of Contents for Simoco SRM9000

  • Page 1 MRMap - www.mrmap.org.uk MRMap-GPS-Tracking-Communications-Safety-Mountain Rescue-Mapping-Downloads-Free Software Rebroadcast Manual Simoco SRM9000-Based Radio Rebroadcast & Repeater Devices. Collated By The LDSAMRA Communications Sub Committee On behalf of the contributing teams of the North West of England and Southern Scotland. Rev C 14 January 2009...
  • Page 2 All re-broadcast devices are based upon current Simoco radio equipment and thanks are due to Team Simoco Ltd in Derby and Huntingdon, and TMC Radio Pty Ltd in Australia for their help in resolving issues that arose during the construction of these devices.
  • Page 3 Introduction:- The concept of re-broadcasting:- The devices to be described are intended to act as two-way signal enhancement units to enable radio communications into difficult-to-reach areas. To this end, a system using two simplex transmissions on different frequencies has been adopted where the Base or Incident Command Post (ICP) transmits and receives on one channel and the Hill-Parties do likewise on their Team Working Channel (TWC).
  • Page 4 The General Principles of Rebroadcasting As you will see in the following pages, re-broadcast is not a lot different in effect, from manual relay. The same vehicle in the same position could handle both methods. The only real difference is that there is now no need for the vehicle driver to relay massages to base. The argument that manual relay takes a team member off the hill is not really valid as most if not all teams have people who’s hill-going days are a memory rather than a fact.
  • Page 5 What re-broadcast does is to fill in the gaps on those occasions when the main system struggles to cope. You wheel it out in just the same way you would your manual relay vehicle. Under some circumstances, it doesn’t even have to be a full-blown team vehicle anyway. These devices can be fitted to virtually anything that can provide them with power as Penrith and Bowland Pennine have both shown.

  • Page 6: General Principles

    General Principles - The Old Way—Manual Relay from a vehicle Direct communications from the base, May not be !*^$*! possible with the party on the opposite side of the Radios hill. The signal from base will just pass over their heads or be absorbed by the intervening hills.
  • Page 7 General Principles Not in the spirit of the thing! You could park a vehicle as high as you can get it but this is bad for relations with the neighbours and bad for the level of interference you will receive your- selves from teams in other regions who are probably operating correctly so you have no re-dress.
  • Page 8 General Principles The New Way—Automatic re-broadcast from a vehicle For re-broadcast to work successfully, it isn’t necessary to take the vehicle to the top of any hills. It only needs to be in a position where both the base and the hill-party can be satisfactorily contacted from the vehicle.
  • Page 9 Optimum Position Planning. It’s possible with a little work, to pre-plan suitable locations for known radio black-spots. The free, on-line coverage calculator provided by ATDI can give a coarse prediction of coverage for a given location. In the example below, a location at a view-point on the A684 Garsdale Road gives an indication that it would permit re-broadcast from the Kendal remote site at Singleton Park, out to the Cautley Spout area where comms are otherwise impossible.
  • Page 10 By using the FreeWare ‘RadioMobile’ application, much greater accuracy can be achieved when plotting optimum coverage of fixed or mobile sites. Radio Mobile software is a copyright of Roger Coudé VE2DBE. Radio Mobile is dedicated to amateur radio and humanitarian use. Although commercial use is not prohibited, the author cannot be held responsible for its usage.
  • Page 11 First Steps - The Simple Approach to Rebroadcasting. The following information is based upon documentation published on the TMC Radio website and research carried out by various teams. It represents variations on broadly similar systems that increase in complexity as they go on. Ideally a team radio officer would select the version he or she feels is most appropriate for their own team.
  • Page 12 SRM9000’ series radios. Rebroadcast can be achieved using other manufacturers hardware Low Band but the extremely simple way in which this is achieved with SRM9000’s, and the number of variations available for experimentation, means they are hard to beat under these circum- stances.

  • Page 13: Cross-Linked Cable

    This diagram shows the pin-out and part number of the Crossover lead. It can be made up to virtually any length using standard CAT5 components. From Simoco, the cost is about £12. All SRM9000-based versions of the re-broadcast device require this cable to be fitted.
  • Page 14 (Programmed to be Low on Tx) Speaker connections - pins 6 and 13 Pin 3 - the Ignition sense connection. Pin 3 should be linked The SRM9000 power and facility connector. to the adjacent positive supply pins to ensure switch-on.
  • Page 15 The TMC Radio ‘Simple’ Repeater This is the simplest form of rebroadcast/repeater possible using Simoco SRM9005 radios. Normally no speakers would be connected and there is no control head. Because both radios operate on frequencies that are not too far apart, some interference between the two is to be expected.
  • Page 16 The High Band Rebroadcast Channels This aerial significantly higher and Vertical Aerial Separation. than the other. “In-Band” Rebroadcast. Defined as :- Both radios are in the same radio frequency band. In this case, both are high band. 147.350 MHz Crossover lead If the currently designated VHF rebroadcast channel of 147.350 MHz is to be used instead of a low band channel, then the risk of mutual interference between the two radios is high.
  • Page 17 Very roughly the Diplexer works as follows; In order that the in-band radios can operate side by side without de-sensing each other, a device called a diplexer (or duplexer) can be used. This is basi- cally two independent filters. One is tuned to the frequency of one radio and the other to the frequency of the second radio. Diplexers are not required when cross-band re-broadcast is used.
  • Page 18 A simple rebroadcast device capable of operating on your own Team Working Channel and a few others near to you would be built like this. This is the ‘Simple Repeater’ as described in the TMC Radio publication A9k-501. The only difference is the addition of the diplexer allowing use of frequen- cies, in both radios, that are close to each other.
  • Page 19 The TMC Radio ‘Simplest’ Repeater This is probably the method that most teams initially looked at and the one several teams now use. It works fine with a little training and it’s only real fault is the need for three radios and two aerials for each vehicle.
  • Page 20 This approach is only partially successful for a number of reasons, the main one being system but not both. that it requires three SRM9000’s to make up the complete communications system for a rebroadcast vehicle. Some teams may accept this in view of the ease with which the system can be set up.
  • Page 21 The black cable shown top left of the picture is the cross-over cable. The one supplied by Simoco is red in colour but this one was made up for the job. Notice that the speaker leads have been left un-connected.
  • Page 22 A Transportable Rebroadcast Device. The board-mounted version shown on the previous page can be more securely mounted and used in exactly this format as demonstrated here by Kaz Brush of Penrith MRT. Looking like it might take the blast from a small nuclear device, you can see it still isn’t much bigger than the component parts used to make it up.
  • Page 23 The TMC Radio ‘Standard’ Repeater This is where things get a little more complicated As already mentioned, the problem with the previous version is the need for a separate radio to handle normal voice comms to and from the vehicle when the rebroadcast device isn’t in use. It’s possible to have only two radios handle the job of both normal comms and rebroadcast but you are now into the realms of additional accessory boards.
  • Page 24 The ‘Practical “Standard” Repeater’ is designed to provide the missing socket needed for the fitting of a control head to the two SRM9000’s that make up the rebroadcast section. This allows us to do away with the third SRM. It also requires some programming to be carried out on both SRM’s in order that we can control whether the radio is operating normally or in rebroadcast mode.
  • Page 25 Programming the ‘Standard’ DMAP Repeater For all versions of the rebroadcast device, the ‘Minimum Speech’ setting must be 15. Leaving it at ‘0’ will result in no transmitted audio from your repeater. Program one button (F3) for “Repeater Mode”. Program F4 for “Auxiliary”. Label the button screen displays as shown - ‘REPEAT’...
  • Page 26 For portable, out-door use, Bowland Pennine MRT have encased the whole rebroadcast unit in a Peli-box. Shown here with the internal top-plate removed, the device has everything self-contained with the exception of the ae- rial and power supply. This device has been deployed on a number of occasions and Iain at Bowland Pennine has accumulated a considerable...
  • Page 27 The current best option for display capabilities and easy of reading, is the 9030 control head. Also a control head option, the 9022. This incorporates all the functions of the 9030 but in a completely hand- held device. For use in Bowland’s Peli-box system, it may have advantages when it comes to mounting and use.
  • Page 28 A recommended improvement providing a more elegant solution to the problem. Here, the suggestions again get a little more complex and the ability to follow an electrical diagram is a great help. We have to stress here that any additional assistance needed with these configurations can be got from either myself or the contributing team.
  • Page 29 From work carried out by Alan Prescott at Keswick MRT, it’s been discovered that the repeater function provided by the DMAP board, is not strictly necessary. If the crossover cable is connected to the existing front RJ45 sockets on each SRM9000, then rebroadcast mode is entered as soon as power is applied to both radios in much the same way as it is in the ‘Simple Repeater’.
  • Page 30 Programming for the Modified TMC Radio Repeater The output pin DB15-8 is programmed to go High when button ‘F3’ is pressed. Alongside this button, the screen display will read “REPEAT”. When Rebro is active, this will be preceded by a chevron.
  • Page 31 Manually Switched Rebroadcast Mode Probably the easiest and most efficient method of implementing vehicle comms and rebroadcast from a pair of SRM9000 radios. This configuration doesn’t rely on programming of the radios in order to achieve switch-over from standard vehicle comms to rebroadcast. Instead it uses a basic change-over switch which, when operated, powers both the secondary radio and the aerial change-over relay.
  • Page 32 The Modified TMC Radio “Standard” Repeater , alternative suggestions. The MA-ASIG Board As the repeater function is now being provided by the crossover cable and not by the DMAP board as in the previous example, it is pos- sible to dispense with this board in favour of the very much cheaper MA-ASIG board. This, again provides the necessary additional socket re- quired in order to fit a control head.
  • Page 33 Although a much easier solution, the previous example was still complicated by the fact that the diplexer needs to be present to keep the frequencies in each radio, apart. If a cross band system is used where the rebroadcast link from the vehicle to the base is on a different band, the old low band channels being the most obvious for experi- mentation, then no diplexer is needed and the system is very much simpler to setup.
  • Page 34 The Modified TMC Radio “Standard” Repeater, alternative suggestions. The Low Band Uplink It’s clear how much simpler the low-band uplink channel would make life. The need for a diplexer and aerial switching is completely re- moved although the vehicle will still require two aerials, one low band and one high band. This is the option chosen by some of our colleagues in Scotland and there is a lot to be said for it’s use by English and Welsh MRT’s.
  • Page 35 Extending the Capabilities of the Standard Repeater. At this point there are hopefully enough options for you to select one you think will suit the needs of your team. Most of those requiring buttons to be programmed on the control head can also be used with simple dash-mounted switches. It’s perfectly possi- ble to mix and match the methods used in each of these examples.
  • Page 36 Additional Variations Applicable to Most of the Devices shown so far. - Selcall Control Setting up selcall (Selective Calling) is a topic in it’s own right and anyone who wants more detail is advised to contact the teams where work has been successfully carried out with this system.
  • Page 37 Dave Binks at Duddon & Furness has designed and adopted a system where both radios can be independently used on all channels and a significant level of control via selcall is available. Individual rebro vehicles may be remotely activated and the user is advised as to which rebro he or she has just switched on. Operation of the system is best left to his own words and the following section has been supplied by Dave.
  • Page 38 THE DUDDON AND FURNESS MOUNTAIN RESCUE TEAM REBROADCAST SETUP Intro Rebroadcasting to most radios officers was a challenge, but to the average team members it meant absolutely nothing. After a little education, most then realised the benefits, although that was as far as many wanted to go. They were not interested in how it worked as long as it did. With this in mind, and the fact that we have large parts of our area that are not in radio range of the base without rebroadcasting, my aim was to make the system as easy to use and as idiot proof as possible thereby gaining the widest acceptance and subsequent usage by all team members.
  • Page 39 (Continued from page 33) Base As described previously it is envisaged that base has overall control over selecting which repeater is required, changing them as required by hill party move- ments. Switching a repeater on is achieved by pressing one button on the base radio, once for repeater 1, twice for repeater 2, three times for repeater 3 and four times to turn them all off, then change the base radio channel to Rebroadcast.
  • Page 40 I am able to intercept selcall control sequences, intercept key presses, change the radio channels, write text to the control head display, switch the digital output used to switch the RF relays in the diplexer box, set the volume, enable the repeater mode and send out additional “beeps”. Simoco were very helpful (after I had finished what I wanted to do) and have sent me source code for the repeaters mode.
  • Page 41 A Remote Channel-Changing Fixed Repeater System designed To Remove The Need For Leased Telephone Land-Lines. A number of teams in the Lakes use remote radio sites that are controlled over a leased telephone line. These have been found to be both expensive and prone to fail- ure from all manner of events from lightning strikes to a not so gentle shove with an earth-mover.
  • Page 42 The primary radio setup for the team Base It’s important to understand that the radio used at your base is on a single low band channel. It can’t be used for direct comms to your portables on the hill. You should always have a ‘local’...
  • Page 43 This configuration will only work if the correct firmware files have been loaded into the SRM9005 radios. These are non-standard upgrade files and are available from Team Simoco Ltd Under the heading ‘Mask’ the last three digits are the channel associated A single frequency (here 86.3125MHz) is programmed repeatedly into the...
  • Page 44 Options that could be used at Base A second control head that offers full control of the remote radio from a location other than the control room. Extension leads are available to give up to 100 metres separation. A desk top ‘goose-neck’ micro- phone is available for the SRM9030 to replace the standard fist micro- phone...
  • Page 45 The Equipment At The Remote Radio Site. Two Simoco SRM9005 Radios, No Control Head High band SRM9005. High band Programmed with all aerial UKSAR channels required. The programming order must be the same as is in the Base radio. The selcall sequence...
  • Page 46 Moffatt MRT’s Suggested Rebro System: The following suggestion came from James Coles of Moffatt MRT and has considerable merit for it’s stated purpose. Eventually a significant number of teams will be using these devices and the chances of mutual interference goes up accordingly. Any means by which we can reduce this risk will increase the usefulness of the re-broadcast devices and allow more than one team to operate simultaneously with others with the minimum of interaction.
  • Page 47 The Schematic for Moffatt MRT’s suggested system. Any signals received by the rebro vehicle on the TWC are re-transmitted back to the base. Both the hill-party AND the base operate on the TWC. Although the 147.350MHz frequency can be monitored by the hill-party, it isn’t necessary for them to use it. Control of the audio output levels on both base radios would need to be good to avoid howl-round and a head-set would probably be better suited than loud-speakers.
  • Page 48 James’ system is interesting from the point of view that in Scotland, they’ve not used low band and never did have as many channels as we in the Lakes ended up with. As he points out in the accompanying emails, getting his colleagues to change channels is not as easy as we will find it as it has no historical precedent.
  • Page 49 An alternative approach to rebroadcast systems in team vehicles This method uses the additional facility terminals available on the main power connector instead of the standard crossover lead. This leaves the radio RJ45 port available for other tasks if required.
  • Page 50 This group of 4 connections are used to provide the facility connector rebroadcast function The pin 3, ignition sense contact Normally associated with power and loudspeaker connections, the 15 pin D connector can also provide audio in and out plus two programmable pins, one, an input and the other an output.
  • Page 51 An Alternative Approach To Rebroadcast Tx/Rx Tx/Rx AUDIO AUDIO Rebro Rebro Channel Radio Pin 3 to Pin 4 Ignition Sense Normal Vehicle On/Off Pin 3 to Pin 4 Ignition Sense TWC Radio Rebro On/Off Switch If required, a control head can be fitted to the TWC radio via the The connections between Pins 14 and 15 on both D-15 connectors should RJ45 port.
  • Page 52 The picture on the left shows the whole rebroadcast setup with the lid off. The radios are standard SRM9005s but are fitted into a TSF2000, 1U, case and not in their normal individual aluminium boxes. The necessary heatsink is on the bottom of each radio. The RJ45 port on the left-hand (TWC) radio is connected to MRMap running on my Eee PC and the device to the left of the computer, is the diplexer.
  • Page 53 This is only possible because the cross-over functions have been provided by the facility/power connector and not the Simoco cable that normally fits in the RJ45 sockets. These remain available for use with controllers etc. Here they have been extended to the...
  • Page 54 The switch marked ‘Rebroadcast On’ supplies power to the secondary radio so turning the device into a rebroadcast unit or repeater if a suitable config file has been loaded into the radios. If this switch is in the ‘Off’ position then power is only supplied to the team working channel radio.
  • Page 55 If the normal style of case is used then accessory boards can be fitted. As the repeater/rebroadcast function is now handled by the facility connector and not the RJ45 sockets, these remain available for anything else you might want to fit. If a dual control head MA-ASIG board is fitted then both a control head and a computer can be connected.
  • Page 56 The rebroadcast version of this setup has been tested using CTCSS on both receive and transmit for all radios. Voice and GPS data both passed through the system at range without any apparent difficulty. The current operating frequencies are 147.350 MHz for the rebro link channel and Langdale’s team working channel of 156.175 MHz.
  • Page 57 Half Duplex Operation Using the 155.350 MHz and 147.475 MHz Pair Hill-Party Tx on 155.350 and Rx on 147.475 Base Tx on 155.350 Radio A and Rx on 147.475 Programmed Rx only on 155.350 Radio B Programmed Tx only on 147.475 Portable radios would need to switch to a simplex TWC for handset to handset comms.
  • Page 58 That’s basically as far as the current design section goes. We haven’t covered everything that can be done and we probably never will but hopefully there’s enough information in these pages to help others gain the best from their systems or even to inspire someone to come up with a better one! If that happens, I hope that you will send the details along so that we can share out the information amongst all the teams.
  • Page 59 A number of the circuits shown in this document are not really practical for reasons explained on that page, however, they would all work as rebroadcast devices as the fundamentals of operation are adhered to throughout. Two SRM9000 radios and a crossover cable.
  • Page 60 Notes and things to be aware of:- 1...The alternative front panel supplied with the DMAP board and carrying the 25 pin ‘D’ connector, does not need to be fitted if the facilities available on the 25-pin connector are not going to be used. Don’t fit the ribbon connection to the DMAP board and use the existing front panel by knocking out the pre-cut covers over the RJ45 connections.
  • Page 61 Vehicle Positive Supply Relay Coil Switched supply to the secondary radio IN4001 Diode Negative supply via pin 8 on the power connector Protection Diode when a relay is used. 6...There is also room in Roger’s box, to fit one of the suggested Maplin or CPC relay ‘cards’. These are usually negative voltage triggered and their input pin just connects to pin 8 of the radio power plug.
  • Page 62 11...A mast of some sort used to augment the existing roof height of the vehicles does provide a very significant increase in the performance of these devices. The operationally easiest of these masts is the pneumatic, pump-up, variety although there are others.
  • Page 63 17… If you are setting up two SRM9000 radios for use as a rebroadcast system even if one of them is also going to do service as your vehicle’s main comms radio, the ‘Mute Speaker During FFSK’ option must NOT be checked. Doing so will prevent the data...
  • Page 64 getting through the system altogether. It will also, fairly obviously, result in the received data being heard in all it’s glory by the vehicle radio. That, for the time being, is something we have to live with I’m afraid.
  • Page 65 Programming Interface for the PRM80 and SRM9000 series Radios. For those who want to wire up their own...
  • Page 66 Programming lead for the Simoco SRP8000 and SRP9000 series hand portable radios...
  • Page 67 Contacts :- Component suppliers and information suggestions:- General information regarding this document:- ‘Simple’ and modified ‘Standard’ repeaters. Team Simoco Ltd:- PRM80 repeaters (See ‘Notes’) Andy Gamble Remote channel-changing fixed repeater Business Development Manager Rob Brookes Mobile: 07710 738171 LDSAMRA Comms Projects Officer DDI: 01332 375591 Robert.brookes@btinternet.com...
  • Page 68 MRMap - www.mrmap.org.uk MRMap-GPS-Tracking-Communications-Safety-Mountain Rescue-Mapping-Downloads-Free Software Silent GPS Data Reception on a Simplex Voice Channel Silent GPS Data Reception on a Simplex Voice Channel. A Guide for Team Communications and Training Officers. MRMap Development Team 10/01/2009...
  • Page 69 Normally associated with power and loudspeaker connections, the 15 pin D connector can also provide audio in and out plus two programmable pins, one, an input and the other an output. These can be programmed to go either logic high or low when certain conditions arise.
  • Page 70 An Alternative Approach To Rebroadcast That Doesn’t Use The Standard Cross-Over Cable. Tx/Rx Schematic Tx/Rx AUDIO AUDIO Rebro Rebro Channel Radio Channel Radio 13.6v Pin 3 to Pin 4 Pin 3 to Pin 4 Ignition Sense Ignition Sense The connections between Pins 14 and 15 on both If required, a control head can be fitted to the TWC D-15 connectors should be made using screened radio via the RJ45 port.
  • Page 71 The image on the left shows the whole rebroadcast setup with the lid off. The radios are standard SRM9005s but are fitted into a TSF2000, 1U, case and not in their normal individual aluminium boxes. The necessary heatsink is on the bottom of each radio.
  • Page 72 Just program the necessary channels in your radio with the tone 218.1Hz on both Tx and Rx. In the case of Simoco radios it’s also a good idea to program one of the function buttons for CTCSS disable in case you need to knock off the tone mute.
  • Page 73 This is my own radio so as you would expect, the MRMap data addresses are for my own callsign. Here you would substitute your own information and the correct values for your team. ‘FFSK Data Rate’ is always 1200 baud. ‘...
  • Page 74 The Base Radio Programming the base is essentially the same as for the portable radios. The Data Ad- dresses are changed to reflect the fact that this is a base and no GPS data is being sent so no FFSK ANI or GPS Reporting is necessary. Polling of the portables is handled by MRMap not di- rectly by the radio itself.
  • Page 75 Programming the Rebroadcast Radios. This is where all the work was involved and where all the mistakes were made. A portable radio working directly back to a base radio where both use full CTCSS has always resulted in si- lent GPS data. Getting it to work through the rebroadcast device needed a lot more work. Set the Radio Type to 9005 External Serial The majority of problems are caused by the fact that when the red cross-over cable (it doesn’t...
  • Page 76 Of critical importance are the ‘Data Volume’ which must be set at 15 and the selection of ‘Telemetry Output’ ‘Data Volume’ sets the audio signal level on pin 15 of the rear facility (power) connector and is the volume of the signal sent to the transmitting radio. A level of 15 causes no distortion of the FFSK data whereas larger values can and lower values just reduce the audio volume.
  • Page 77 Next to be programmed is the Input/Output values which are shown below. Don’t be tempted to use ‘Valid Signal’ instead of ‘Carrier Detect’ as this means the data, which doesn’t have a CTCSS tone attached, won’t enter the rebroadcast unit so only the voice signal is sent.
  • Page 78 Programming of the TWC side of the rebroadcast unit is the same for the 147.35MHz radio but for the actual frequency used. The need to use a diplexer with an in-band rebroadcast device means that it’s not really much use in programming any other frequencies in but this has the advantage of there being no danger of popping up on the wrong channel as there’s no control head to tell you you’ve done this.
  • Page 79 FFSK from being passed through the device. With the ‘FFSK’ values, a discussion with the engineers at Simoco Huntingdon resolved some logical issues that had been causing difficulties. Again the FFSK Data Rate remains at 1200 baud.
  • Page 80 Not all of these were SRP9100s or indeed, Simoco radios and in none of them was the FFSK data audible when CTCSS was enabled on receive and transmit.
  • Page 81 The basic rebroadcast functions are now provided by the crossover connections fitted to the rear power/facility plug. The standard Simoco crossover lead is not required for plain, single channel rebroadcast. However if you have a system on which you need to be able to change the operating channel via your link radio, then the addition of the cable described here will enable that for you.
  • Page 82 What to watch out for and what didn’t work:- When programming a rebroadcaster for remote channel changing, the ‘Remote Options’ checkbox needs to be checked as shown below. Radio Type - SRM9030 Secall options page However, if you’ve already set the Radio Type on the first page to, ‘9005 External Serial’ as rec- ommended then a number of programming options disappear.
  • Page 83 One where I’ve so far failed miserably is putting a single selcall tone onto the end of the transmis- sion made by the rebroadcast radios so as to act as an indication that you are still within range of base. This is sometimes called a ‘Comfort Tone’. I couldn’t get a tone at all from either of the rebro radios using ‘PTT Data Ext’.