[txzeke]

I sent off an eMail to GRE inquiring as to why the volume in the earpiece is so low and having to turn the volume all the way up to hear anything decent when an earpiece is attached.

Here is the reply:

"The design of the PSR-500 is such that the volume is attenuated greatly for any device that is connected to the earphone jack, to prevent possible hearing damage that could result if full power of the audio amp is accidentally routed to headphones.

It is possible to circumvent this by connecting the shield of the earphone connector to an internal ground in the radio, for example, the antenna connector shield. Although this is a simple modification, please understand that as with any modifications it should be done with caution and would be at your own risk. However, doing so will provide full power to the earphone connector. You can test this without opening the radio by using a piece of wire to short the earphone jack shield to the antenna connector shield outside of the radio."

I also inquired on MotoTRBO. If they were going to do an upgrade for the 500 or a new radio.

Here is that reply:

"We are very interested in TRBO but it won't be an upgrade for this radio. TRBO will require all new DSP hardware."