Hello everyone, A couple of weeks ago, I sent Bob, WA1MIK a message thanking him for his fine article on recapping the Spectra radios.
At work, we have a fleet with several hundred 800 MHz Spectra C5 and C7 mobiles. Over the past year or so, they've been dropping like flies. I've now gone through nearly 50 Spectras with various problems, and in all but four radios, replacing the electrolytic caps and cleaning the circuit boards restored proper operation! There were many different symptoms, but the one thing that I saw repeatedly were radios that would work OK when first powered up, and then develop various problems after running a while. Bob's article gives Digi-Key and Mouser part numbers for the replacement capacitors. I've used the Mouser numbers, and they're right on target. On the last batch of radios that I repaired, I did deviate from Bob's parts list in that I used a 10uF/25V tantalum to replace the 10uF/16V factory electrolytics. The reason for the substitution is that the tantalum cap is physically smaller, making it easier to install, especially in the tight spaces near the audio IC. The Mouser part number for this cap is: 74-595D106X9025B2T. Another thing worth noting is that in the three 900 MHz Spectras that I've recapped, the 47uF cap on the RF board was not present. It was present on all of the 800 MHz and 450 MHz Spectras that I've worked on. Thanks again to Bob for his article, and I hope that this posting might help someone else. 73/GL Steve N8NM
