HOME BREW IDEA'S.


This page is designed to give help and idea's to other amateur stations wanting to try their hand at simple home brew projects. I will continue to update this page with new idea's as and when they become available. If you have any home brew diagrams that you think may be handy to others please email them to me and I will include them on this page.




If you are interested in Voice Over Internet Protocol (V.O.I.P) type communications and would like to establish an RF gateway in some instances you will need an I-Link board. When I started with this system ready made boards were not easily available and as I enjoy home brew I manufactured my own board. I am lucky to have PCB manufacturing capability here but realise that most people don't. So I have produced my own board design built onto Vero board (known as Strip board in some countries) for anyone to build. Please click here NOW to download the diagrams and connection information.

If you are interested in building the above item you will need to be able to programme the PIC 16C of 16F84 micro controller device. This is not as hairy as it sounds and you can easily build a device capable of doing just that with just a few common components. Again I have produced the circuit to be built on Vero board and you can download the information by clicking HERE now. In this zip archive I have also included the software that you will need to do the actual programming.

Some newer pieces of V.O.I.P software such as Echolink and Eqso as well as a lot of S.S.T.V. and PSK 31 software now employ comport keying for controlling the transmitter PTT. A simple small circuit using a single transistor will suffice to do this job very well indeed. The following circuit should suffice in most cases.

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You simply pick off the RTS line from the COM port you are using for switching the transmitter PTT in conjunction with the above circuit.

Yet another way of triggering the PTT line is by the use of VOX. In this instance the actual audio output from the sound card speakers can be used to control the PTT line of the transmitter. I believe that this method to be not as successful as the others but with a bit careful tweaking you can get it working quite well. Once again the circuit is produced for Vero board and you can download it by clicking this LINK now.

In the UK here the repeater's are normally accessed by using a 1750hz tone burst prior to transmission. A lot of people use modified PMR or commercial radio's modified for use on the VHF or UHF band's. Most of them do not have the capability of sending a 1750hz tone burst burst so a simple one can be built to do the job. You can download this Veroboard design quickly by CLICKING HERE.

I hope that any of the above may be useful to someone. This way you actually get the enjoyment (and sometimes the heartache LOL!!) , and the sense of achievement of building and getting something working for your self.

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