XPR XPR6550 wont transmit on DMR repeater channel

[KD9RTX]

I just picked up an XPR6550 and got a few simplex channels and a local DMR repeater programmed in to start playing around with MOTOTRBO. I've programmed other amateur oriented DMR radios before so the software isn't too dissimilar to those so I figured I'd be able to find my way around. The simplex channels work fine although the TX audio is kind of low from the 6550. It seems to receive great.

The issue I'm having is that I can't seem to transmit on the DMR repeater I programmed in. All I get is two short green flashes of the LED and a low continuous tone. My TYT MD-UV390 shows now activity and I've confirmed that I can hit this repeater with that radio. I even fired up the SDR and set it to the input frequency of the repeater and it shows now transmission.

I've triple checked the TX and RX frequencies, color code and time slot and they all match what I know to work with my TYT MD-UV390. A little more research showed that failing to select a contact name is a common mistake so I made sure I had a few digital contacts to try and that I had one selected on that channel by default. My DMR ID is set in the radio ID field and I think I've tried every admit criteria for that channel.

I'm pretty much out of ideas at this point. Any advice on where to go from here? Really hoping there is some setting I haven't found yet that is causing the problem.

 

[YL3IM]

What hardware is the repeater in question made of? If it's a homebrew one, looks like the transmitting part is slightly off frequency. Your Motorola may not be getting the response when trying to establish the initial handshake whereas TYT works because of its loosy receiver.

 

[KD9RTX]

According to the Club website it's a Motorola SLR5700

W9YB DMR Repeater

But according to the Brandmeister page it's an SLR5500. Not sure what the difference is or what the hardware actually is.

W9YB Brandmeister

 

[Project25_MASTR]

How off frequency is the XPR6550? They aren't very tolerant to being off frequency...

 

[KD9RTX]

I have no way of knowing. It's possible it could use an alignment. It is used after all. Here's another problem I've noticed that I suppose could be related.

I tried transmitting on one of the local GMRS repeaters but was unable to open the machine. My XTS radios and that TYT DMR radio I mentioned in my first post have no trouble. Watching on my SDR I confirmed it is transmitting the correct DPL code and I can receive ok on the repeaters output frequency. I'm only 2.5 miles from the tower and my XTS5k worked fine even on low power from inside so it shouldn't be a power issue.

 

[soundguy215]

According to the Club website it's a Motorola SLR5700

W9YB DMR Repeater

But according to the Brandmeister page it's an SLR5500. Not sure what the difference is or what the hardware actually is.

W9YB Brandmeister

5500 is the EMEA model while the 5700 is the US and Canada model. No different hardware-wise.

 

[KD9RTX]

Well I figured it out. Turns out the antenna it came with was a dummy load. Something must be broken inside. Found a BNC adapter that worked and tossed a dual band HT antenna on it and it works great now.

Wish I'd tried that sooner.

 

[AM909]

... The simplex channels work fine although the TX audio is kind of low from the 6550. ...

Analog simplex? Isn't ham still wideband, and did (or can) you set the bandwidth/channel spacing for it?

 

[KD9RTX]

Ham is wideband. I have the wideband entitlement and those frequencies set correctly. Part of the problem was the bad antenna probably, but I also noticed that the microphone is in a different spot than most of my other radios and that I'm taking into the top of the radio instead of directly into the mic. Once I figured that out things sounds a lot better.