• To anyone looking to acquire commercial radio programming software:

    Please do not make requests for copies of radio programming software which is sold (or was sold) by the manufacturer for any monetary value. All requests will be deleted and a forum infraction issued. Making a request such as this is attempting to engage in software piracy and this forum cannot be involved or associated with this activity. The same goes for any private transaction via Private Message. Even if you attempt to engage in this activity in PM's we will still enforce the forum rules. Your PM's are not private and the administration has the right to read them if there's a hint to criminal activity.

    If you are having trouble legally obtaining software please state so. We do not want any hurt feelings when your vague post is mistaken for a free request. It is YOUR responsibility to properly word your request.

    To obtain Motorola software see the Sticky in the Motorola forum.

    The various other vendors often permit their dealers to sell the software online (i.e., Kenwood). Please use Google or some other search engine to find a dealer that sells the software. Typically each series or individual radio requires its own software package. Often the Kenwood software is less than $100 so don't be a cheapskate; just purchase it.

    For M/A Com/Harris/GE, etc: there are two software packages that program all current and past radios. One package is for conventional programming and the other for trunked programming. The trunked package is in upwards of $2,500. The conventional package is more reasonable though is still several hundred dollars. The benefit is you do not need multiple versions for each radio (unlike Motorola).

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KENWOOD 450

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SPRINTERLIGHT

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Oct 16, 2014
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HELLO
Just got my license!!!!
I finally am able to transmit. So far I have made a few contacts and having fun. but fun all ways comes to an end. Radio quit working. I was tuning around the bands and the radio started cutting in and out. I checked the coaxial connection to see maybe it was loose and wiggled it. Yes that's where the problem was. after a few more wiggles the radio quit receiving. a friend had a look at it and we saw the coaxial connection inside the radio had a broken solder joint. He re soldered it and receive works. only now it does not transmit!!!
we went no further as neither of us has any radio repair skills. I read on the web that these radios were common to have this repair.
Can anyone shed any light on where to look to repair
any help is appreciated
thanks
 

rescue161

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You may have fried the PA by transmitting with the antenna connection loose like it was. This would have presented a mis-match and the PA could have become extremely hot and burned it up. Does the radio appear to be transmitting? Does a TX light come on when you press the PTT? Have you connected a Watt meter to the radio? I'm not familiar with this particular radio, but most modern commercial radios will fold back the power when the VSWR is too high, in turn protecting the PA. It could be a number of things.
 

ramal121

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but most modern commercial radios will fold back the power when the VSWR is too high, in turn protecting the PA.
OK, I will jump on my high horse here just once. Fold back the power due to high VSWR. Huge misconception. I see this bantered on many forums. It is stated in the CB forums like it was an industry standard. I would like to see anyone provide me with a schematic that shows a typical CB has any kind of protection against high VSWR. Cheap consumer grade equipment just doesn't have have that. The cost of a few pennies more is not in their business model.

To get the instant protection needed to shut down power in case of increased reflected power a radio would need a directional coupler that is connected to the power control circuitry. Now I'm dating myself but you would only see something like this in a higher end radio like a Motorola Syntor for a mobile type radio.Usually if any protection is implemented it is in the fashion of a thermistor that senses the final temperature and gradually backs off the drive as things heat up. Sometimes it is just software driven, as in the uP reads the PTT is asserted for an abnormal amount of time and assumes an overheat condition whereas it will automatically decrease PA drive. Many ways to do this and don't expect any protection circuitry to be your salvation.

Now to the OP. Running a transmitter with an open or shorted connection or a highly mismatched antenna MAY not cause any problems until the error is corrected. But if the high VSWR presents a voltage node in a critical junction then yes you may experience sparks or smoke that will take out a component that will render your transmit power nil. This could happen almost instantly.

A watt meter will tell the whole story if what the radio is producing is indeed being conveyed to the antenna. No watts out is a bad sign. Another good thing to check is the amp draw on transmit. If a mobile radio pulls 10 amps or more on high power but there is very little reading on a watt meter, then you can deduce the PA is working properly and the transmit/receive switch (usually pin diodes} has gone south.

No way to know for sure unless you can hook up some test gear to figure out where the problem lies.
 
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rescue161

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Hubert, NC
but most modern commercial radios will fold back the power when the VSWR is too high, in turn protecting the PA.
OK, I will jump on my high horse here just once. Fold back the power due to high VSWR. Huge misconception. I see this bantered on many forums. It is stated in the CB forums like it was an industry standard. I would like to see anyone provide me with a schematic that shows a typical CB has any kind of protection against high VSWR. Cheap consumer grade equipment just doesn't have have that. The cost of a few pennies more is not in their business model.

To get the instant protection needed to shut down power in case of increased reflected power a radio would need a directional coupler that is connected to the power control circuitry. Now I'm dating myself but you would only see something like this in a higher end radio like a Motorola Syntor for a mobile type radio.Usually if any protection is implemented it is in the fashion of a thermistor that senses the final temperature and gradually backs off the drive as things heat up. Sometimes it is just software driven, as in the uP reads the PTT is asserted for an abnormal amount of time and assumes an overheat condition whereas it will automatically decrease PA drive. Many ways to do this and don't expect any protection circuitry to be your salvation.

Now to the OP. Running a transmitter with an open or shorted connection or a highly mismatched antenna MAY not cause any problems until the error is corrected. But if the high VSWR presents a voltage node in a critical junction then yes you may experience sparks or smoke that will take out a component that will render your transmit power nil. This could happen almost instantly.

A watt meter will tell the whole story if what the radio is producing is indeed being conveyed to the antenna. No watts out is a bad sign. Another good thing to check is the amp draw on transmit. If a mobile radio pulls 10 amps or more on high power but there is very little reading on a watt meter, then you can deduce the PA is working properly and the transmit/receive switch (usually pin diodes} has gone south.

No way to know for sure unless you can hook up some test gear to figure out where the problem lies.
I did say commercial, not CB. This was posted in the commercial radio forum, not the CB forum. And yes, I see this folding back of power in my job on Harris and Motorola mobile radios.
 
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