Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!rochester!pt.cs.cmu.edu!andrew.cmu.edu!jg2u# From: jg2u#@andrew.cmu.edu (Joseph Gerard Gottlieb) Newsgroups: sci.electronics Subject: Wireless Audio Link Message-ID: Date: Tue, 17-Mar-87 21:38:02 EST Article-I.D.: andrew.MS.V3.18.jg2u.80021112.easton.ibm032.3336.0 Posted: Tue Mar 17 21:38:02 1987 Date-Received: Thu, 19-Mar-87 03:10:33 EST Organization: Carnegie-Mellon University Lines: 34 ReSent-Date: Tue, 17 Mar 87 21:39:01 est ReSent-From: postman#@andrew.cmu.edu ReSent-To: nntp-xmit#@andrew.cmu.edu Return-path: To: outnews#ext.nn.sci.electronics@andrew.cmu.edu Newsgroup: sci.electronics Well all of this talk about wireless data links has gotten my mind in motion. Here is my situation: I am the Chief Engineer at Carnegie-Mellon Universities' campus radio station WRCT. Our studio is located 600 feet (line of sight) from our transmitter, which is located atop a near by building. I would like to devise a a way of relaying audio at 15-16khz between the studio and transmitter. I have looked at STL's (Studio to Transmitter Link's which work via microwave). There are two problems I have encountered with STL's: 1) Expensive ~$6500 + $1000 for the antenna's. 2) It is almost impossible to get a clear frequency in Pittsburgh. You might be wondering "How do you relay the audio now ?". Unfourtunatly our audio is run through 2000' of 9 pair shielded "mic" cable (through a conduit along with the power feed for the building (none of this was my idea it was like this when I got there)). As you may imagine our air signal is less then optimal (read not very transparent). Another option is the use of two 15khz balanced broadcast lines rented from the phone company. But at $4000 per year - no thanks. Here are my requirements: Bandwidth- 15khz Signal to Noise- above 60db (can be lower if necessary) Realibility- Works under all conditions and almost never dies Am I asking for too much? Should I go beg for an allocation and buy the STL? Better yet is there a way to send an audio signal of very good quality (transparent, high S/N, 15khz bandwidth) over a 2000' run of mic cable (for a relitivly low cost) ? If someone could figure out a way of doing this they could make a killing in the broadcast industry. Many thanks. Joey Gottlieb Chief Engineer WRCT-FM Pittsburgh