Centracom Gold Elite audio cutting out

[70 cutlass 442]

I am working with a Centracom Gold Elite dispatch console and have been having issues with audio on one channel cutting out. This is not a global issue but specific to a single channel on the system and am currently working on ruling out the radio and tone remote as the culprit (we use control stations and are not interfaced directly into the repeater). The issue is pretty sporadic but happens enough to pose a major concern. Dispatch will be receiving a very clear signal and the audio just disappears as if the user was keying and unkeying the mic. I have ruled out any squad radios as well as the repeater, and from the looks of it, the radio and tone remote will not be the issue either. Any input on where to begin?

Though I have limited knowledge on this system, I am doing what is within my capability so when I call in a vendor we will not waste time/money to trouble shoot parts of the system I was already able to rule out.

[jmfirefighter20]

Hello,

The first thing I would do is change out the BIM module in the CEB. The BIM modules are the cards that slide in. You do have a spare, correct? If you have a pile of them, make sure you're using the right kind as there are several different board types. You can compare them visually and by part number if you wish. Make sure you also change the address of the replacement board to match the original board. There will be a little red switch block on the bottom of the card, component side. Make sure the white dip switches are in the same position on both boards.

When changing out a card, just pull straight out. Dispatchers will get a static sound and error message, so let them know what you are doing. Just slide the new card in until it "pops" in, and everything should come back up as long as the card is the correct type and the address is right.

Just a few questions as well:

How many OP positions? Does this happen on ALL the OPs?
What is the transport method between the remotes and the control stations? Copper wire, ethernet/IP, etc? Have you verified that it's fine?

[70 cutlass 442]

Hello,

The first thing I would do is change out the BIM module in the CEB. The BIM modules are the cards that slide in. You do have a spare, correct? If you have a pile of them, make sure you're using the right kind as there are several different board types. You can compare them visually and by part number if you wish. Make sure you also change the address of the replacement board to match the original board. There will be a little red switch block on the bottom of the card, component side. Make sure the white dip switches are in the same position on both boards.

When changing out a card, just pull straight out. Dispatchers will get a static sound and error message, so let them know what you are doing. Just slide the new card in until it "pops" in, and everything should come back up as long as the card is the correct type and the address is right.

Just a few questions as well:

How many OP positions? Does this happen on ALL the OPs?
What is the transport method between the remotes and the control stations? Copper wire, ethernet/IP, etc? Have you verified that it's fine?

Thank you for the fast reply!

This is 2 position system that uses copper between the stations. We do have a pile of spare cards but what had me confused was, despite the same part number... the replacement card had the jumpers in a different spot on the card than the one I am replacing. I set the address on the new card to the same as the old one, and verified the jumper selection and slid it in as you recommended. The odd part was when I did this, it disrupted the audio coming in on another channel (but not going out on that channel). I was then forced to put the old BIM back into the cage to keep the other channel working. The only relation between the two channels are they are the only two that are recorded. I am heading back to the PSAP to sort through more cards and see if I can find the exact card and try that. I will keep you posted.

[RFguy]

The BIM's have a "squelch" circuit on them that will mute any audio below a certain level. You may have low incoming audio that's dropping below the threshold causing your drop outs.

There are some sensitivity jumpers on the BIM that change this threshold.

[70 cutlass 442]

Thank you for the quick responses. To answer a few questions, this is a 2 position setup using copper between the cage and the CIE. I do have a pile of cards here but the odd part of it all is, despite the same part number on the cards, they appear different. I took one of the "new" cards and changed the address on it to match the problem card and slid it in as jmfirefighter recommended, but this then caused incoming audio trouble on a completely different channel on a different cage. That affected channel could talk out, but nothing would come in... I had to swap the cards back to resolve that new problem. I am on my way to the PSAP now to look through more cards and see what I can find. This has been operating for three years without an issue, so is it common to have sensitivity issues even after it has worked a while? Thank you both for your help.

[jmfirefighter20]

What I meant about they type of transport method was what do you have between the CEB and the control station? What does the setup look like?

You need to make sure the cards match exactly....jumpers, dip switches for address, -everything- when you are swapping cards. Sorry if that wasn't clear.

I know in my 5-position Centracom I've had BIM cards go south and exhibit broken audio and quiet audio in both directions. Swapping cards was the solution. Of course, my Centracom is almost 20 years old now......

[Jim202]

What I meant about they type of transport method was what do you have between the CEB and the control station? What does the setup look like?

You need to make sure the cards match exactly....jumpers, dip switches for address, -everything- when you are swapping cards. Sorry if that wasn't clear.

I know in my 5-position Centracom I've had BIM cards go south and exhibit broken audio and quiet audio in both directions. Swapping cards was the solution. Of course, my Centracom is almost 20 years old now......

A word of caution here on just randomly swapping cards. There is audio level adjustments that need to be at the correct levels. You need a audio level meter to be able to adjust these boards correctly. Poorly adjusted audio levels will effect both RX and TX directions. Best you have the technicians involved with what your doing.

Maybe if you have enough cards, you can get the techs to set them up for you and then put a tag on them for what channel they are for. then you only have to worry about the address jumpers.

The other issue here is some of the BIM cards are set up for DC control, some cards are set up for E & M control and some cards are set up for tone control. You need to make sure you have the exact same kind of board. Just the part number is not enough. There can be an add on board that controls the function of the board.

As has been said before, you need to make sure "ALL THE JUMPERS ARE SET THE SAME". Missing a jumper is not the same as the BIM card you pulled out.

Jim

[jmfirefighter20]

A word of caution here on just randomly swapping cards. There is audio level adjustments that need to be at the correct levels. You need a audio level meter to be able to adjust these boards correctly. Poorly adjusted audio levels will effect both RX and TX directions. Best you have the technicians involved with what your doing.

Maybe if you have enough cards, you can get the techs to set them up for you and then put a tag on them for what channel they are for. then you only have to worry about the address jumpers.

The other issue here is some of the BIM cards are set up for DC control, some cards are set up for E & M control and some cards are set up for tone control. You need to make sure you have the exact same kind of board. Just the part number is not enough. There can be an add on board that controls the function of the board.

As has been said before, you need to make sure "ALL THE JUMPERS ARE SET THE SAME". Missing a jumper is not the same as the BIM card you pulled out.

Jim

Absolutely. Forgot to mention that you'll need to realign the audio levels with the "new" board.

For diagnostic purposes however to "rule out" the CEB as being the issue you have, a card swap for the exact same unit as the old one is a quick way to determine if it's a problem or not. If the cutting out audio stops, well you found the issue, but the audio could have level issues, thus the need for realignment.

Thanks for popping in and stating that Jim.....been a bit since I've swapped cards......

[70 cutlass 442]

Thanks for all of the input. We had our local Moto dealer here for 5 hours and they were unable to diagnose the problem. I now have a feeling that this is a problem before the console as our logger is picking up the drop in audio and that is punched into the 66 block prior to the console. I will try running some new wires and see what that does.

[alex]

Look closely at the wiring from the 66 block to the logging audio recorder. Look at what pin the audio comes from on the 66 block. The Centracom has logging audio output that is different than the 2 or 4 wire control points on the block. That logging audio flows through the BIM. If you have a bad BIM then you likely have bad logging audio. Just something to pay attention to and check. I don't remember the specific order of the wires but it is well documented in the Centracom documentation.

[Bill_G]

When diagnosing a Centracom problem, the first thing I *don't do* is swap BIM cards. I check the levels coming in. As already mentioned, there is a line squelch setting on the BIM that could be clamping on low audio because the telco circuit has an issue. Anywhere from the BIM block on the wall, through the telco, all the way to the base station, could be the cause. Most common failure is wet splices in buried cables. But, without knowing how your system transports its audio between the prime site and the remote sites, it's speculation how to proceed.

[70 cutlass 442]

Thank you for the input thus far. I will do my best to explain what I have found so far... BTW, our local Moto dealer told us it is a radio issue in all of the squads.... lol

We have all of the tone remotes terminate at a 66 block. From there, wires are punched down to another 66 block with a spark gap on it and then it goes off into the CEB. The two channels we are having issues with (PDF1 and DPW) share a common 66 block. This block is separate from all of the other channels as these are the only two channels that use MDC1200 and the installer kept this completely isolated from the other channels to help make issues like this easier to diagnose.

I have good audio coming from the tone remote block up to this block, but audio returning on the logger output on the block has the same issues as the operator positions. Note, these are both MDC equipped, but are obviously on their own MDC and BIM cards.