Re: EE RF question Yes, that is what I'm trying to do.  I think that this would eliminate  interferance.  Though the price is tethered operation.  I guess it  doesn't really have to be a coax.  It can just be an RCA A/V cable right? Or how about a single wire!   ----------- ericson mar  Robotics Consultant mar@cooper.edu (212)353-4356 Department of Mechanical Engineering  The Cooper Union for the Advancement of Science and Art  ------------------------------------------------------- On Tue, 3 Aug 1999, Jose-Afredo D. Esguerra wrote: > Pherd, >  > It sounds as though he is planning on patching the output of a RF > transmitter to the input of a RF receiver. >  > 73's, >  > Jose >  >  >  >  >  > -----Original Message----- > From: FThompson9@aol.com  > To: handyboard@media.mit.edu  > Date: Tuesday, August 03, 1999 7:41 PM > Subject: Re: EE RF question >  >  > >In a message dated 8/2/99 7:38:41 PM Central Daylight Time, mar@cooper.edu > >writes: > > > >> > >>  If you have an RF Transmitter and Receiver with Antennas, can you detach > >>  the antennas and just connect a co-ax cable between them?  I'm guessing > >>  this would reduce the noise and interferance to a minumum.  Is this > right? > >> > >> > > > >I'm not to clear on what you are describing here.  Generally speaking I > would > >say yes, you can slap a piece of coax in without too much loss of function. > >But you really need to know what type of antenna your feeding, the radio's > >frequency, the impedance expected at the terminal by the > >transmitter/receiver.  If you wish to read up on it, I suggest going to > your > >local library and finding a book call "The 19xx ARRL Handbook for radio > >amateurs" (where xx is the year of your choice).  This book gives you > enough > >information to design your own radios and antennas. > >    If the antennas in questions are just "rubber ducks" (short whip > >antennas), I wouldn't worry too much about the feeding system.  Just about > >any antenna system is better than a rubber duck.  The ones that I have seen > >are just resistors with slightly longer than normal feed lines.  Yet these > >tiny devices can be found on a large number of radios communicating over > long > >distances. > > > >Hope this helps, > >Pherd > > >  >