Blown finals and tranceiver cooling

 Blown finals: these are the two most dreaded words

 Blown finals: these are the two most dreaded words that a radio owner wants to hear, but it is a sad fact that too many radios end up with this condition. If only radio heatsinks were double or triple the size, the finals will stay cooler and last longer. But then they would be more expensive because of added materal and shipping cost. The picture shows two devices that will keep things cool. The water cooler is perhaps extreme as it is very difficult to make. It requires machine shop skills to mill aluminum well. However the temperature monitor device is a very affordable accessory that most homebrewers can construct. You can even rig a relay and fan to it. FM rigs suffer most from blown finals because of the duty cycle -100%. IF you use SSB, the radio will be cooler but SSB has never come close to becoming mainstream as a mobile "daily driver". DMR is a good choice if you are looking for a new mobile. Since it operates 50% duty cycle because of the TDMA (time division multiplex) technology, it heats up less. For portable users , you have the added benefit of longer battery life too. With this in mind, one should avoid FM and even C4FM because they are 100% duty clycle power hogs. Just search for FM and C4FM repair videos on youtube and you should see the trend. GO DMR! They are way COOLER!



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First "Fun with Morse Code" Inter highschool Contest photos

Imahe
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Kenwood HF-50Mhz TRansceiver TS-680V Review Digest

Imahe
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Hot-Rod Your ICOM IC-725-Series Transceiver by Jukka Vermasvuori

Imahe
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