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voltage ft-1500m

Posted: Tue Oct 18, 2011 7:59 pm
by mja20
I have a ft-1500m and am having some probs. How much voltage does this radio need in order to operate?

For some reason when I key the mic it cuts out when I have it on full power. However it seems okay when I only have it set up on half power or 2/3s power. its set up in a truck and running on a battery and alt.

Odd thing is it never used to cut out like that before. Any ideas? or more info needed?

Re: voltage ft-1500m

Posted: Thu Oct 20, 2011 8:20 am
by fineshot1
Most two way radios operate at optimum @ a steady 13.8VDC, this is most critical during transmit.

Have you measured the battery voltage while transmitting on the radio at full power?

How old is the battery in your truck? Perhaps it is starting to fail and this is the first sign of that
or perhaps there is a SWR problem with your antenna that is causing the radio to shut down with
a high reflected power output.

Check those items and post back with the results.

Re: voltage ft-1500m

Posted: Mon Oct 24, 2011 9:24 pm
by mja20
I guess that must be it. The radio shows the voltage going to the radio when you first turn it on an shows only about 13.1-13.4. Must be shuting down when the voltage is to low. Anybody know a way to boost the power going to the radio? maybe a higher voltage alternator?

Re: voltage ft-1500m

Posted: Tue Oct 25, 2011 8:33 am
by fineshot1
mja20 wrote:I guess that must be it. The radio shows the voltage going to the radio when you first turn it on an shows only about 13.1-13.4. Must be shuting down when the voltage is to low. Anybody know a way to boost the power going to the radio? maybe a higher voltage alternator?
I am not sure what you mean by "The radio shows the voltage going to the radio". Can you please re-state that.

Are your voltage measurements while the vehicle is running and at the vehicle battery posts or at the radio,
and how is the radio connected to dc power?

One can not "boost power" connected to a radio. If you are measuring at the batt posts lower than 14.2VDC while the vehicle
is running then you most likely have an alternator or battery problem.

Re: voltage ft-1500m

Posted: Thu Oct 27, 2011 1:29 am
by mja20
Sorry if that was unclear. If I have the truck running, then press the power button to turn on the radio (ft-1500m), For a moment (a second or two) the screen on the radio shows the amount of voltage it is receiving at that moment. Usually around 13.1 to 13.4. Sounds to me from what your saying is the alternator needs to put atleast 13.8 to the radio for it to function.

I guess I can test it at the battery post to see if its getting a different voltage number then what the radio is measuring. Sounds like I need a new alt. as its not putting out enough power.

Thanks for the help

Re: voltage ft-1500m

Posted: Thu Oct 27, 2011 9:13 am
by fineshot1
mja20 wrote:Sorry if that was unclear. If I have the truck running, then press the power button to turn on the radio (ft-1500m), For a moment (a second or two) the screen on the radio shows the amount of voltage it is receiving at that moment. Usually around 13.1 to 13.4. Sounds to me from what your saying is the alternator needs to put at least 13.8 to the radio for it to function.

I guess I can test it at the battery post to see if its getting a different voltage number then what the radio is measuring. Sounds like I need a new alt. as its not putting out enough power.

Thanks for the help
ok - now i understand, thanks for the clarification.

I would never trust what the radio tells you the voltage is. Take independent measurements with a dvm of known reliability
and that way you can be 100% sure what is happening. If the radio is not functioning properly you can not trust its voltage
displays. While the vehicle is running you need to test the dc voltage levels at the battery posts and at the radio power cord
to be sure of what you have. If there is no difference and the voltage is 13.8 or slightly above you are ok. If there is a big
difference between the two or the voltage is much lower in either place then you have problems with a voltage regulator or
a voltage drop somewhere in the vehicle wiring.

Re: voltage ft-1500m

Posted: Thu Dec 01, 2011 11:49 pm
by mja20
Wanted to say drop back and say thanks. Still acts a little funny on certain frequency, but overall better since I replaced the alternator on the truck., thanks for the help :)

Re: voltage ft-1500m

Posted: Mon Dec 12, 2011 3:08 pm
by fineshot1
mja20 wrote:Wanted to say drop back and say thanks. Still acts a little funny on certain frequency, but overall better since I replaced the alternator on the truck., thanks for the help :)
You are most welcome & happy holidays to you & your family. :)