In the beginning, they were crystal controlled. It was like ancestor to frequencies. Scanners that were crystal controlled were expensive and placated on the part of the police department that wasn’t as stable as other parts of it—financially. In addition, they were only used for scanning local police and fire departments by local citizens as commonly as watching Saturday morning cartoons, which meant scanners weren’t exclusively for the police. By the 1980’s, keyboard-programmable receivers became widely available, playing in favor of the police’s pocketbook, as these receivers quickly replaced the crystal-controlled scanners. In mid-1986, Radio Shack released the PRO-2004, which changed the industry and the consumer market for scanners. It had 300 channels in ten scan banks and continuous coverage from 25-250 and 760-1300 MHz. After this, other companies were in close competition to follow in Radio Shack’s footsteps, then leading to other models that were continuously better. Police scanners were quite cumbersome in the beginning, yet they became to evolve and became easier to obtain and …show more content…
Many departments began using digital voice modulation techniques, which could not be heard on the scanners. Likewise, their scanners could only follow “mixed-model” systems, which had an analog control channel and used a lower bandwidth. Because of this, digital scanners became expensive compared to their analog counterparts. This was due to patent licensing costs for the digital voice compression technology. To revert back in cost effective means, several departments are now using other digital protocols which currently can’t be heard on