1st make sure you aren't in a valley or low ground that inhibits FM (presume you're talking about FM). FM Reception is "Line of Sight" out to the Horizon. Signal does not follow the curvature of the earth. If your antenna can't "see" the transmitter tower, you get no signal or bad reception. Hills, trees, bldg's that are higher than you reflect the signal off into other areas. So get your antenna up as high as you can (within reasonable costs and safety). Google FM reception. Then Google FM Multiplex reception. It's more detailed than the basic's I just gave you. Usual FM reception is generally good up to 25 miles (dependent on transmitter power, line of sight, weather, etc.) and fringe reception out to 40 miles in most cases. Fringe reception has a lot of hash in it. Multiplex will have some hash in it because of the way multiplex is sent (via an AM carrier wave) that is stripped off at the multiplexer, where L & R channels are separated, and sent on to the receiver amplifier. Multiplex take a stronger signal to work correctly.
Having said that, which particular tuner/receiver are you talking about? The service manual can walk you thru an alignment, BUT 1ST if it's a tube model, make sure all the tubes are GOOD, pins are clean and straight, and the sockets are clean and tightly grip the pins. Multiplex Stereo DEMANDS a tightly and correctly aligned RF and IF stages. If they are off by even a tiny bit, the Multiplex won't work correctly. Don't work on the FISHER as a 1st project. 99% chance you'll mess up. Find a AM/FM radio you don't care about and practice on it. A good set of tweakers (plastic) and a multimeter will get you in the ball park (as long as you have a steady hand and tiny movements. It don't take much on a tuning coil to get it out of sync.
At this stage, probably best to find a radio shop, or a HAM club in your area. A good amount of the older guys have the knowledge and equipment to do alignments.
