These are just basic ideas.Adding filtering to the output of these types of transmitters would keep them from interfering to other frequencies.Check out the link below to get a better idea of a finished device.
Here we go with some fun stuff
I was really bored lately.So,I decided to make due with the time I have waiting for summer.If you have a license and want to make a simple propagation beacon,here are some very easy projects.First,a tiny 50mhz transmitter.
3 wires connected to a 50.000mhz crystal oscillator found in my old linksys router .Power,ground and the antenna.This thing puts out a signal clearly on frequency to my scanner.How much RF?Who knows.But it will be connected to a descent antenna and soon transmitting my call.These oscillators can be found almost anywhere,and CHEAP! Oh,and yes,that is a cdrom audio cable.
My odds and ends page has more info.
Old CB walkie talkie using 28 MHZ crystal.
This Claricon walkie talkie is one of the oldies.Maybe 100 mW output?I found a crystal @ 28.224.9mhz on a PCI 56k modem.Popped it in the walkie,and bingo.Transmits clearly on 28.226.5 mhz..Looking forward to a report with this one.My regular 40 channel CB radio is taking a break while I enjoy this one.It is in testing so the connections are a bit crude.By the way,the crystal used here looks like a very short HC49U,so be sure to look at those shiny crystal like objects on your PC junk.
One of the good ones :)
This thing has been sending N2NXZ/B for almost 24 hrs with the same 9V battery.
Finished product
Everything is back together.Left jack is power and right jack is keyer.This beacon sounds pretty unique at 28.226.I will guess @ 100 mW.I found the original manual and it claims 100mW with a 2 mile range.For a test,it was about 2 miles away and could be clearly heard here at my QTH using a mobile magnet mount antenna.This beacon will operate here replacing my normal 28.2278 - 3 watt CB beacon until it heads out to the remote site.So far it has been running 10 days on a 12V-4AH battery.Maybe using my 12V - 125AH battery and a 9 volt regulator I will not need a wind generator?At least it will use less power than the other.
UPDATE 05/24/09 - This beacon is now operating using KC2VCG/B at our remote site using battery power on an aluminum dipole antenna.
Just when you thought I was finished
Here is an old 27mhz RC controller.I expected to find a typical 27mhz crystal in it.Nope,it had a 13.4975 and was used as a doubler.The only crystal I could find in the 10 meter band was a 14.31818 mhz.I felt that if it transmits on 28.636,it will most certainly work in the beacon band.It sure did,a booming signal.Guess where I found it?On an ISA sound card.Matter of fact,most of my computer junk has that crystal all over the place.
You know what prompted me into these projects?The price of crystals today !!! "Holy cow". I hope some of you found this stuff to be interesting at least.If you want to share what you have done with these ideas,please use my comment area and share your experiences.Now go get those old toys and computer parts and see what you got.73
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