How to create a PMR446 gateway repeater...|
Posted Mar 16, 2003 - 11:34 AM
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A "how-to" on joining our PMR446 gateway network using your radio as a PMR446 internet link and eQSO...
Please check before setting up a repeater that doing so is lawful in your Country. Please also remember you need to contact us (firstname.lastname@example.org) for a callsign before setting up a gateway on our server.
When you drop us a mail please include your e-mail address in the body of the mail (this makes it easier to grab it out rather than looking at the mail source), your location, preferred channel and an idea of when your gateway will be on air ("will vary", "24/7" etc). If you have joined this website as a member, please also include your member nickname and we will upgrade your status which will give you access to the gateway ops only forum.
It is also illegal to connect a 27mhz CB so, sorry, UHF only.
Please do not put a gateway in 446ENGLISH until you are sure it does not cause "bouncing" (this is where your gateway keys up during other peoples overs) - this means your squelch settling is set too low in eQSO.
Lastly, please read Using our eQSO server.
We've made this a public server but it's run on our time and expense (each audio stream, and that means each person/gateway connected, uses 15kbs) which is why we ask you to contact us first so we can issue you with a callsign for your gateway. This makes it easier for us to monitor our bandwidth requirement and contact you in case of a problem, and also help out if you're having trouble by having an email address for each repeater gateway link. We hope to do this by database on the site soon so it's automated. In the meantime just email email@example.com with your location and frequency you want to use and we'll give you a callsign.
If you connected a gateway with a made up callsign or hf/cb link, got kicked from the room, muted or banned and you're now reading this, that's the reason why! In which case you'd better send us an email and we'll get you properly sorted and restored.
eQSO for PMR446, written by M0ZPD (Paul), is a voice over-IP application that allows you to connect your radio to your PC as a PMR446 gateway and connect that gateway to our server via the internet and thereby to other users who have done the same. The PMR446 version was written by Paul for us to run this network for PMR446.
As an example of what this does, someone within range of my gateway link (about a 2 mile radius from my location in Greater London) can talk through my radio, over the internet, and out through another gateway rebroadcasting on PMR446 in, say, Belgium or Sydney Australia (on UHF CB). Anywhere in the world in fact. Someone within range of that second repeater gateway can then communicate back and thus establish a conversation.
Anyone with a PMR446 radio which has a "VOX" setting to automatically activate the push-to-talk (most PMR sets) can set this up. There is no need to modify your radio at all. You just need this software and two cables - one to go from your PC soundcard line out to your radio microphone in socket and one from your radio speaker out socket to your PC soundcard line in socket.
Obviously the more gateways that come online to the system, the more coverage there is. It's a similar system to that utilised by mobile telephone networks.
If you already know how to use eQSO or prefer to busk it then feel free, but bear in mind the following:-
1. Download the latest PMR446 version of eQSO from our downloads page.
2. To connect you must type in our servername "eqso.446user.co.uk" and the room ID "446ENGLISH" then press connect. If you download the gateway version from our downloads page, this is already pre-programmed as preset #1.
3. We would at least urge you to at least read the bottom few paragraphs of this text relating to setting up your VOX settings.
To connect a radio to eqso you must download the gateway version of the software from our download page as opposed to the PC user version. Once downloaded, we'll set up your sound card.
Double click on the volume control icon next to the clock on your taskbar and you should find yourself at the volume control window. If you have elected to use the mic socket on your soundcard (actually, we strongly suggest you use the line in instead as the speaker output of these PMR446 radios is quite hot) then you need to find the mic control and to prevent feedback you need to mute this. Similarly if you are using line in then you need to mute the line in volume control.
Next select the recording properties (options, properties then recording) and make sure that your chosen method of line in or mic is enabled and checked.
CONFIGURING THE SOFTWARE
Start up the software, fill in your callsign in the callsign box (or "ACS" if you've e-mailed us but want to get up and running immediately), put in the comments box a brief description of your gateway preferably based on the protocol we've adopted (copy the style of comment used by the Surrey repeater UK001-L). Make sure that the VOX box is ticked. Occasionally the server may drop momentarily (like when we need to reboot it), by ticking the auto reconnect box the software will attempt to reconnect to the server automatically. The speed, frequency and volume boxes are for the morse
identifier and courtesy tones, these are best adjusted to suit individual needs, just adjust each one individually and click on apply until you are happy with each setting.
The courtesy tones, force id and id if idle are again user preference settings. Courtesy tones plays the (default) letter k in morse at the end of each over over the radio, force id plays your callsign in morse at intervals set by the server (usually every 10 mins) again over your radio as does id if idle. This makes a useful range transponder so you can test your repeater yourself by keying transmit on another radio and waiting for the morse letter "k" to be beeped back at you by the repeater a few seconds later.
Squelch settling is another control that may need fine tuning to your own particular set up, this is the amount of time that the software prevents you from sending audio down the internet after your PTT has switched off. This prevents "tail chasing" which is the crunch of static heard after you drop the PTT button.
This causes all the other gatway links currently connected in the room to "bounce" each other in a continuous loop, so it is vital that you get this correct. If in doubt, set it high (1500ms) and reduce it slowly as you get used to the software over the next few days. If your gateway starts "bouncing" you'll know that you have decreased it too far.
NOTE The eqso software needs shutting down and restarting after each adjustment is made to the squelch settling.
Next step is to click on the rig-keying button, you will then be presented with another window. Here you must first select the method with which you are keying the radio. You can use either the VOX setting or the continuous tone setting. Vox simply triggers the PTT on receiving a voice signal (the same as your radio does with it's own VOX setting, but this time for transmission). We recommend the continuous tone setting because VOX can get a bit choppy if people leave long pauses in their overs! The continuous tone mixes a sub-audible tone onto the audio received from the internet, which keeps the vox unit keyed up during pauses in received audio.
The default frequency of 80Hz has been found to be satisfactory in most cases, though the audio level of this tone may need increasing. I use a volume setting of 5000 on my Goodmans Tracker Mark II.
Check out Dr Rob's article on building a com-port keyer for even snappier overs!
FINE TUNING AND TESTING
Now to get on air and fine tune things. Connect to room 446ENGLISH and our server eqso.446user.co.uk and wait for someone to start talking. Or transmit and ask for assistance from anyone in the room. If all is well when someone else transmits in the room your radio should go into tx and using a separate receiver you should be able to adjust the level of the transmitted audio using the output slider until the audio is clear and undistorted. If not go back and check your connections and settings.
Next preferably in the off-air room (to avoid causing disruption) set the squelch on your radio to a suitable level to prevent any noise breaking through. Using your other radio start transmitting and you should see your repeater callsign highlighted in the window and be able to monitor your audio levels on the VU meter. Using the mic slider level on the software and the radios volume control set the audio peaks on the VU meter to about half way up the meter MAX, and definitely not into the red as audio distortion will occur.
When you are happy with these settings check that when your radio stops transmitting that your callsign does not momentarily become highlighted again. If it does it means that your squelch settling is not set correctly and that the "crunch" of noise that occurs when your radio stops transmitting is being sent down the internet. Increase the squelch settling time by 100ms a time until you stop this from happening. Don't think it's strange if you need a squelch settling time of 2000ms or more - some radios do require this. Anything less than about 2250ms is fine - the server has an internal setting of 2250 anyway so anything less than this will not affect other users.
Setting VOX/Silence levels: Set silence fully to the left, put vox slider right at the top. Turn on vox, talk into the mic while moving the vox slider down until the server acknowledges you are talking. You will lock the room up while you are doing this so be quick! Now be quiet and move the silence level to the right until the server says you have stopped talking.
Clicking on the "See who's on the system" button will launch the monitor application and show you a tree of all the servers, gateways, rooms and PC users currently on the network.
If you have any questions or comments, please post them on our forum.
Hope to hear your PMR446 gateway radio on the air soon,
Dean & Tj