Omnipresent Audio…
Reached a milestone with my 500mW transmitter project today so I can control the audio around the house. It works well and is very stable based on the BH1415 FM transmitter IC, the type used in these crappy FM transmitters used for plugging your MP3 player into a car stereo… Somewhat superseded by a hundred different other configurations nowadays, it has a 3 stage RF power output which should technically be quite efficient. Need to design a small antenna now, may have a go at etching one onto a PCB if I can find any info on the subject. My original idea was to build it into an aluminium cast box and design in feed through points for power and line inputs and have a 50 Ohm BNC antenna output and inductively load a short antenna similar in length to the 802.11 types of old, this now seems a tad O.T.T. and if I am going for the internal antenna design, a rethink will be required. Chucking it all in an ABS box with a bit of spray plating may well be the way to go, or fitting the ally module into a plastic case… Hmmm
Add comment August 31st, 2013
With a lot going on at the moment I can’t do a great deal, one of my projects this summer is to repair and dry-line the shed so I have a room where I can work, this however is becoming increasingly difficult with the ever spiraling family budget and Her Majesty’s obligatorily among others eating into my income. Another project is an HF antenna system that might meet with objection from a neighbour or two, my plan now is just to put it up and see what happens, I think making it an issue for approval may force them to consider that it could be more of an obstruction that it actually will be and they will oppose it. Perception of my plan could get exaggerated and I know how much some people like a drama. It also involves digging up the lawn for the grounding system, so early autumn may be a wiser choice of timing, I have a way of getting the other half on board with the idea of digging the lawn up and that is to design the ground plane using copper tube with holes drilled along it’s length for irrigating the lawn in dry weather, just a small addition of a 3/4″ MIC for a Hoselock connector required at the starpoint.