APX 4500 Wattage output

[KF5YBV]

I'm having trouble with my 4500. I recently had trouble talking into a repeater in an adjacent county. My transmission had come across as static. After being told i was unreadable, I used a different mobile and was able to talk into the same repeater just fine. After a little bit of think, I decided to check the output and found that the radio was only putting out a total of 5 watts. The strange part was that the radio was showing that it was in High Power.

Is this something that can be fixed using the radio itself or is this a problem that has to be fixed using the CPS?

Also, for information, the repeater used is an analog repeater and in the radio, the tones are correct and the transmit and receive frequencies are correct.

 

[mmckenna]

Two likely scenarios:

1. The channel you were using was set to "low" power. If there isn't a "high/low" power button programmed into the radio, then yes, you'll need CPS to reprogram the radio. Before doing that make sure that the license you are operating under while using that repeater allow it.

2. The final RF amplifier has been damaged. Sometimes sections of the RF amp will take a hit and what you'll get is just exciter power or a very low output. If the radio has bee programmed for high power and it's only doing 5 watts on all channels, then this might be the issue. A trip to depot land would be in order.

 

[KF5YBV]

Two likely scenarios:

1. The channel you were using was set to "low" power. If there isn't a "high/low" power button programmed into the radio, then yes, you'll need CPS to reprogram the radio. Before doing that make sure that the license you are operating under while using that repeater allow it.

2. The final RF amplifier has been damaged. Sometimes sections of the RF amp will take a hit and what you'll get is just exciter power or a very low output. If the radio has bee programmed for high power and it's only doing 5 watts on all channels, then this might be the issue. A trip to depot land would be in order.

There isn't a High/Low power button programmed on the radio. But if i'm not mistaken, doesn't the "H" in the top row of the screen mean High Power?

In the department that we use these radios for, all of out fire trucks have these radios installed in them, plus my Personal Vehicle and they are all doing this. Could it be a miss programming somewhere, because all the radios are programmed the same, or could it really be the RF amplifier?

The only difference between the radio in my POV and the radios in the fire trucks is that the radios in the trucks are remote mounted with the Green O2 Head. Mine is solid mounted to the radio body with a Grey O2 head.

 

[KevinC]

Maybe someone has set the high power setting to 5 watts in CPS.

 

[KF5YBV]

Maybe someone has set the high power setting to 5 watts in CPS.

That may be the case. Just didn't know if that was possible because I am not familiar with Motorola's CPS.

 

[KevinC]

That may be the case. Just didn't know if that was possible because I am not familiar with Motorola's CPS.

Yes it's possible. It's under "General Settings".

 

[vans113]

when you put it on a watt meter , did you check reflective power also? If so how much?

 

[KF5YBV]

I did not check the reflective power. Was just using an SWR Meter in to a dummy load.

Here's my next question. To take a radio to the depot to get reprogrammed, am I going to remove the remote head and take it with the body of the radio or can the radio be programmed without the head?

 

[vans113]

I'd check for reflective power first could be just an antenna issue. 2nd the radio can be programmed on the brick itself when it's converted to remote mode. You can plus straight into the front of the radio on the brick. ( where the remote cable would plug into) and program it just fine


Sent from my iPhone5 using Tapatalk

 

[mikewazowski]

He should have very little VSWR when using a proper dummy load.

Check your settings in CPS first then make sure your per levels are set correctly in Tuner.