posted 8/11/06
Today the WA8ZWJ repeater gained access to the Internet via EchoLink. This has been an ongoing project for many months.
Last month Glenn, W8AK retuned the exciter (Kenwood TR-8300) and back up exciter (also a TR-8300) for the 442.850 repeater. While he was doing so, he discovered that a resistor would need to be inserted into the circuit to prevent loading while injecting PL Tone into the transmitted signal. Below are several pictures of the two 8300's after they had been modified to accept the PL Tone injection. It was necessary to inject the tone at the proper point because the repeater audio feeds the exciter at the mic input which would have filtered out the PL Tone if it had been mixed with the transmitted audio from the controller. Doing this kind of mod enables us to get by with one encoder that feeds the primary exciter and back up exciter rather than having separate encoders placed in each one.
We had already set up the EchoLink Computer at Lou, N8KXM's residence across town (Lou has a high speed Internet connection and ZWJ continues to hold onto dial up technology). A Mitrek receiver is being used at the repeater site to receive the EchoLink signals from the Internet. The audio coming from EchoLink is transmitted on a coordinated link frequency. The COR and audio are then fed into the controller as a secondary receiver. The EchoLink receiver at KXM's listens to the output of the repeater but only passes audio that is accompanied by the COR (Carrier Operated Relay) from the main receiver. This is accomplished by the injected PL Tone which is only active when the COR is active at the main receiver. This way the folks on the EchoLink end do not hear the repeater beeps, identifier, etc. Lou and Keith had done most of the ground work, but were slowed down with part of the installation process. John had a side trip to Columbus, Ohio and stopped by to tidy up the loose ends and get EchoLink going on the machine.
During the final installation set up, John realized that the resistor value used in the exciter mod was a bit too large because the PL encoder board already had some resistance included to assist with isolation. So, a secondary mod was necessary to both the primary and back up exciters. Once it was decided that audio levels and proper control was being routed through the controller, it was necessary to go to Lou's and make the final adjustments to the EchoLink Computer and Mitrek transceiver there. After a couple of hours of effort, we had our first EchoLink QSO with Dave; W8TVC, Mike; N7LMJ and Jim; KA8SFL through the EchoLink setup on the W8TVC repeater and WI0OK repeaters in Traverse City, Michigan! Yee haw!
The EchoLink access locally at WA8ZWJ/r will remain somewhat limited to the local IOOK'ers through a series of commands that will not be available for general consumption. This is being done in order to limit the "casual" activity for those who do not normally use the repeater.
Below is a snap shot of the local repeater cabinet for the 442.850 machine. There are an abundance of wires running to and fro that make everything happen. Sadly, it is not as pretty to look at as Glenn, W8AK's machines, but, it does work!
All the lids are back on the various components and things do look better now than they did for this snap shot. :-)
There are other IOOK EchoLink connections which are active. They are: NN3V, W8JUK (22664), W8TVC (56464) and WA5KUB (23624). The node number for the WA8ZWJ/r link is 269089. If there are other IOOK EchoLink nodes that are active, please notify WA8ZWJ and they will be added to the list.
A very special thank you goes to John, KF8KK for all his efforts in assisting in getting EchoLink up and running.
Also, a very special thank you goes to Glenn, W8AK for his assistance in maintaining the machine.
A super thank you and a tip of the hat goes to Lou, N8KXM for providing the Internet access that makes our EchoLink connection possible!
Best 73, Keith, WA8ZWJ
