10 Metre Echolink M1BGB-L Node Number 387253

M1BGB-L 10 Metre Echolink gateway Node Number : 387253 Location : Frome, Somerset (ST764477) Power : 10 dBW ERP Antenna : 18ft vertical (gain 0) Mode : FM Narrow Frequency : 29.630 Mhz CTCSS : NONE Morse Ident : MB7IJA

The 10 Metre gateway is available with no CTCSS required on 29.630 Mhz FM. You will need a reasonably high deviation to access it. Sending DTMF tones in the way described below will drive it, if you dont have a DTMF microphone consider getting your hands on a handheld DTMF tone dialer, I use one with no troubles :-) Some mobile phones make DTMF noises when the keys are pushed, held next to the microphone this can be good enough.

2 Metre Echolink MB7IJA-L Node Number 362737

MB7IJA-L 2 Metre Echolink gateway Node Number : 362737 Location : Frome, Somerset (ST764477) Power : 7 dBW ERP Antenna : 3m vertical (gain 6) Mode : FM Narrow Frequency : 145.2875 Mhz CTCSS : 77Hz Morse Ident : MB7IJA

Usage
Having set the correct CTCSS side tone try sending it DTMF tones. If the gateway is idle then sending it a * will prompt it to identify itself, this is a good test for access. If its connected to another echolink node then sending * will have no effect, in that case you can always hangup the link with #. Sending a node number as DTMF tones will connect you that gateway, see this link for a list of currently active nodes. Send 001 to connect to one of my favourites at random.
This page details the DTMF functions in full.

If you store sets of tones in your radio then you need a delay between each tone of at least 180ms (250ms is ideal). Short tones with a 250ms delay between each tone will give the most reliable results.

Inside the box, 10m link

Inside with DTMF decoder, click for larger image

The 10 metre box I constructed from scratch, the 2m link is using off the shelf hardware. The Glowing fans on the 10metre box are used to cool the 9v linear regulator and amplifier. The amplifier is rated at 20 Watts (14v), at 9v it gives just over 8 Watts, but remains nice and cool. The gateway tends to have long TX cycles so its a very good idea to stop the amplifier from generating smoke (bitter experience here!).

I started off using the software tone decoder, its not that reliable so I decided to build a hardware one. I was feeling cheap so I looked around and found a 7780 tone decoder chip and a PIC and built one on tri-board. Its not nice or award winning but it seems to work.
The LEDS are the 4 bits + strobe from the DTMF decoder - makes life simpler when debugging. For anyone else trying to do the same the echolink software expects 2400 baud, 8 bits, 1 stop bit. I bodged the format and just send "DTMF KEY in ASCII" + "SPACE" + CR as a string. The echolink software just seems to treat it as a keypress and maintains the timers for you.