I picked up two of these really nice Cobra 86XLR base station radios today. Only $15 for the pair. Back in the day this was a high end radio and it includes a built in power supply and a large front-facing speaker. I only had time to bench test one of the rigs. It did not come with a power cord so I had to jumper in 120 volts to the internal pins (disclaimer: very dangerous! Not for newbies!). I will hardwire a safe, permanent power cord after everything else checks out.The microphone does not work. I suspect a dirty switch is the culprit and will deal with that later, or maybe wire a base mic.The guts are very clean. No burns or leaks. The yellow/green alligator clips are the 120 VAC I jumped in. The other side of the SWR meter is a 50Ω dummy load. I got about 4.5 watts out on an unmodulated dead carrier. The radio would not transmit when the mic was keyed, but it would transmit when I shorted out the mic pins. So i tried plugging in the mic from the second radio and it worked normally. Problem resolved!It’s important to make sure the radio works, especially if you are going to store it for use later. You do not want to find out after a radio has been sitting on the shelf for years that the mic doesn’t work! Clean the switches and do an on-air test to check the audio. Place the radio in a plastic bag or wrap it with food wrap and if possible include a desiccant pack. Label every package with its contents and the date. Organize yourself so you can act quickly when SHTF.
This is the unmodulated RF out displayed on an oscilloscope. It’s hard to see in the photo, but in the upper right corner of the scope screen it shows a frequency of 27.203 mHz. This agrees with what I measured on a separate frequency counter. For this test, the rig was set to CB channel 20 which is 27.205 mHz. Only 2000 hertz off spec…not bad for an almost 40 year old radio and well within the range of acceptability. The output frequencies of these old radios may change after they warm up for a while. Also, the drift will not necessarily be the same on all channels. To really know how good the radio is, I would have to leave it on for an hour or so and then repeat these tests on every single channel. It’s just CB and I’m not that much of a purist…so this is as far as I’m going unless problems come up that need further investigation.
Neither of the 86XLR’s will be given away…I’m keeping these jewels for myself!
As a ham I admit guilt to being snobbish towards CB. But “after further review” I’m moving towards incorporating it into my preps. CB will never be a major player, but at a cost of only about $10-$15 per station, it’s foolish to totally write it off.
Everyone: Go make some room on the prep shelf for a few CB radios! They are more useful than you think