W1HVN wrote:Just recently, a VHF XTL5k in mobile setup with UHF and 800 5ks has started to randomly "boop". All connections check out, voltage at connector is tested to be at 13.8v +/- 0.1 as well as voltage at ign sense. Radio set to Ign Sense Only for power-up in CPS. Radio has not done this when only on battery power from what I can test just on alternator/engine power. Takes usually about 10 minutes before it will start on a drive, then it comes and goes (sometimes beeping over and over) without reason that I have been able to determine. Conectors are tight, and other 5ks do not have any issues at all.
Also, when on battery power, the 5k when the battery is less than optimum for voltage attempts to power on (Red, Amber, Green Light FLash) then quits and retries, and this power up attempt continues. Other two power on 100%.
Ideas?
What different triggers can cause the radio to boop non its own?
Seems CPS tuner does not have a voltage setting and config.
One member has guessed voltage regulator.
Any info appreciated. Purchased used, no warranty available. Worked flawlessly for some time (except power on issue which was the case from my taking pocession) RF Specs out good for this radio with great rx sens and dead nuts on freq, good dev.
Thanks
The first thing I would do is to pull out the digital volt meter and start some looking. I would start at the vehicle battery. Measure the idle voltage before you start the engine. Record the reading. Start the engine with nothing turned on. Record the voltage. Then start by turning on the headlights. Record the reading. Put the high beams on and record the reading. Turn on the defroster and record the reading. Turn on the wipers and record the voltage. While your at max load, put the volt meter on AC and go to the lowest scale you have. Look to see if you have any AC voltage over a few mili volts. If so, this is an indication that you have lost one or more diodes in the alternator. One last test here under the hood is to measure the voltage between the negative battery post and the vehicle ground.
If you see anything funny in the voltages, try measuring the difference between the battery post and the clamp the wire has on the battery post. I have seen brand new vehicles where there was a poor connection between the battery post and the wire clamp. Hopefully your not one of those persons that had a bad battery clamp and went to the auto store and replaced the original molded wire and post with one of those clamps that has a clamp to hold the wire to the battery post. Break down and go buy a replacement cable with the molded on clamp. Climb under the vehicle and replace the positive wire that goes to the starter motor.
Hopefully you are seeing a voltage that stays at or above 13.8 volts. If it goes below that, you have an alternator problem or your mechanic has turned down the idle speed of the engine to try and save fuel.
Another problem may be that you have an old battery. Old batteries loose their internal resistance ans they age. This causes the capacity to act as a noise filter to diminish with age. It also causes the battery to loose capacity to supply high current when you start the engine. One of the first indications that generally shows up is the clock keeps resetting to 12:00 each time you crank the engine. If you see this starting to happen, it's time to replace the battery. You will end up stranded if you don't.
Now back to the radio, now that I have laid the foundation for the electrical system. Again take your trusty digital volt meter and measure the voltage at the radio. I don't mean at the source where you tapped into the electrical system, but after the last splice, fuse, ground or what ever you have placed before the radio. You can pull the high current plug on the rear of the radio out just a slight amount and get your meter probes onto the red and black wire there. Make sure the radio is turned on. I would also do this check in transmit. Get at the red and yellow wires going to the control head. Do the same measurement.
A poor ground wire from the radio to the vehicle frame can cause all sorts of strange problems. Also check the wire from the negative post to the vehicle frame. These smaller wires have been know to come loose, get damages or just left of by some mechanic in a rush to finish a job.
Another note on the XTL5000 that not everyone is aware of, the red wire from the control head needs to go to a hot all the time voltage feed. If not, then the radio will draw about 700 ma when the vehicle is shut off. This will kill a battery in the vehicle overnight in many cases. The yellow wire from the control head can be run off of an ignition feed source to be able to turn the radio off and on with the key.
Hope this provides you with a few places to look for your problem. I suspect that the boop your hearing from the radio is the low voltage sensing in the radio telling it to do a reset. Good hunting.
Forgot to ask, is this radio a newly acquired radio, or is this an old radio that has just arrived and was installed. Reason I ask, is way back when the XTL5000 and the O5 control heads first came out there was all sorts of issues with them. I believe that one of the problems was the control head was turning off randomly. You might want to check with the local Motorola shop and see if they still have a copy of the service note that came out on the problem.
Jim