Batboard

Has anyone else had a problem with THE BIM keying the remote twice at the beginnig of every transmission? When you key the remote with the console it will key, then unkey within .5 second, then immediately key up again for the remainder of the transmission. I thought it could be a bad remote, but It does it with all of them.

Incorrect line levels, clipping in the telco line.

I have tested it little further and it only happens when a talkgroup on the system is patched to the remote through the console. If it is not patched, and you key the remote from the console it keys up normally.

How are you patching it? It sounds like you are using a Maxtrac or GTX type base station for the trunking side of things with some sort of VOX set-up for the interconnect. If so, it's possible when the trunked radio keys up, the talk permit tones are being seen as rx audio & dropping the interconnect for a brief period, if they haven't been disabled.

Actually, if you're patching the talkgroup through Centracom, the above likely wouldn't apply, unless the talkgroup in question is tied to a dedicated base station as above.

Todd

I am using a BIM to connect to a CPI TTP-1 2 wire tone remote. The remote is connected to a CDM1550. The CEB is part of a Type-II trunking system, so we are using the 1550 to patch conventional into our system.

Ok, I was a little mis-lead by your description. The CPI unit is actually a 'tone remote interface', not the actual tone remote. In this case, the BIM is acting as the tone remote.

I can think of nothing that happens during a Centracom patch which would cause what you're describing. The fact the BIM/CDM combination works properly unless there's a patch is puzzling. If it were happening all the time, I would think there were some sort of tone being emited by the CDM upon key-up, such as sidetone during MDC1200 or similar. Depending on the CPI configuration, that could cause exactly what you're describing.

I'll ask you the same thing Motorola would if you call them...is everything in your Centracom system on the same release platform (all BIMs & COIMs and their associated firmware, matching OS/Service Packs, Centracom Software version, etc). Has there been any kind of partial upgrading done since the system was configured at the factory which would cause a mis-match?

Todd

Nothing has been upgraded. It sounds like I am hearing the 2175Hz tone twice when it is patched. Like it keys first for a very brief period, then immediately keys again. Thanks.

rastolz wrote:Nothing has been upgraded. It sounds like I am hearing the 2175Hz tone twice when it is patched. Like it keys first for a very brief period, then immediately keys again. Thanks.

Are you able to put some sort of audio/line analyzer on the BIM output to verify this? If it is indeed only doing this when it's patched, then it would seem to be some sort of release-specific bug which I haven't seen or heard of.

Todd

Yes. I can hear it with a Halcyon hooked up. Our system was delivered in 2000.

Are you sure you are not hearing the following:

2175 high level geuard tone/1950 keying tone/2175 low level guard tone?

Best way is to use a storage scope and actually see the tone sequence, durations, and levels.

George

Check the dip switch settings. A conventional BIM is set different than a Trunked BIM. The bottom dip switch when the board is installed should be opposite from a Trunked Bim I don't have my book in front of me to look it up. I am not sure if this is your problem but it does mess up things.