OK gurus I have a question here. The DIU I have fails a boot up self test with errors 5 & 6. I thought I would mess around with it and see if it would still work. I have an Astro Modem on my wire line card in the Quantro as well as an Astro Modem in the DIU 3000. I can pass both analog and P25 traffic fine to the DIU from the station and get analog audio output on both the Console and MRTI ports. This works as expected. On the DIU Opt 1 General purpose connector I get a nice receiver unsquelch when a valid carrier is on the repeater input also. This side of things works just like I would expect.

When I try to get the DIU to send audio or PTT to the station I get nothing. I am thinking this may be part of the DSP error but I am not sure. I have changed the PTT polarity for both the console and the MRTI ports in the CSS thinking I might be able to get one of them working. I have tried making them active high and low with no success. The DIU never tries to initiate a call to the Quantro. I have verified this listening to the lines going to the station from the DIU and also watched the front panel indications. I am trying my best to save this unit without having to repair it but I am stumped on this one.

Anyone have any ideas?

Regards;
Shane KI4M