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Posted on Friday, November 30, 2001 - 10:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Do I need a fuse holder in line?


You know I must tell you , I see a lot of radios that come into the shop that have been hooked up backwards and still have the same reason why they all go to the CB shop for repair . Someone took out the in line fuse holder or rapped foil around the fuse and guess what? , the next time you hook it up....boom and smoke .
Let me explain why there is a fuse holder in a radio . First of all , rule out the theory that so many CB shops are spreading around that having a fuse holder in line reduces the voltage and current flow . I had a guy come in with an item that had the fuse holder cut out and spliced together and I asked him..where is the fuse? He responded that the local truck stop told him he would have more voltage to the final transistor in the radio and it would put out more power . Oh it put out more power for sure , in a different form of course.....smoke.
ALL CB radios have a diode in the rear end of the radio near the power jack that is rated at a certain current . For example , a 1N4004 diode will withstand about 3 amps of current for a very short time and only let current pass through it one way . If you were to put a diode across a battery in one direction it would no do anything and if you were to remove it and put it across the battery the other way then you would see a spark . This is because the current is flowing through it .
The reason the fuse is in line is to protect the radio from getting hooked up backwards . When the radio is hooked up correctly there is no current flow through the diode . In the case where the radio is hooked up backwards , the current will flow through the diode BUT usually if the correct fuse is in line it will blow because it is current rated lower than the diode current limit and it is in series with the diode . This will stop your radio dead in its tracks from burning up .
Removing a diode so that the radio puts out more power is nothing more than a way for a shop to make a little money in more than one way , the first way is to create the effect that it will put out more power and the second reason is the shop knows that when you do hook it up backwards that you will be back , and this time it will cost you big bucks to replace the 49 cent component .