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Digital oscilloscope project/kit

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John Rudd:
Roy, when you say its not working, can you elaborate a little please? Is there any audio?

Maybe theres no air traffic transmitting? :lol:

wheeltapper:
sorry, I was a bit vague  :hammer:

connecting the bnc socket to a long wire I have in the loft and touching the top of one of the chips with my finger I can barely hear a commercial radio station.

the 3 controls do nothing.

this is with a 9V battery, if I plug in a 12V wall wart the transistor mentioned previously gets hot even tho it's supposed to work on 12V.

there are a few voltages noted on the circuit diagram that came with it , one of them being 12V but there aren't as many as I would like.

I haven't had time to check them yet.

Roy.

John Swift:
Hi Roy

the original project is here -

http://www.sentex.ca/~mec1995/circ/aviarx/aviarx.html


with 1K load resistors I don't expect the transistors to run hot
 but the TO-92 cased 78L08 regulator added to the Chinese circuit  could
 (depending the current taken by the receiver and the volt drop across the regulator)

   John


PS original circuit from http://www.sentex.ca/~mec1995/circ/aviarx/aviarx.html

RobWilson:
 :clap: :clap: :clap: Thank you for taking the time to track down that build page John  :thumbup:

I am sure it will be a great help to me and Roy .

And the http://www.sentex.ca/~mec1995/circ/circuits.htm page looks full of interesting projects   :zap: 

Rob

John Rudd:
The voltage regulator serves no real purpose, there's insufficient headroom from a PP3 battery to allow the reg to function....
I'd be inclined to leave it out....

Just use a current limited power supply when testing the receiver for the first time.... :zap:

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