Pyramid SVR-200 / CDM-1250

[tmtu]

Hi Batlabbers,

I'm looking to do some experimenting with an SVR-200 and CDM-1250... our department is looking to put this into our command vehicle for better fireground coverage...

Anyhow - using MDC is still a must. My question, has anyone used SVR-200s with MDC and had any luck? My guess would be to utilize the trunking option (because of the delay)... would this work with an CDM-1250? Can't find anywhere in the documentation that would indicate otherwise...

Thanks!

[nmfire10]

I assume you are talking about MDC1200 on the CDM. If the CDM1250 is programmed with PTT Pre-ID, then you would have that pre-time to worry about when the SVR200 keys up the radio. The user with the portable could easily forget about that and front end clip themselves while they are talking the CDM is in pre-time. Am I right about your concern? Best solution is to set the portable for Pre-ID and the CDM for post ID. That way the CDM has no pretime and the both radios will get their ID's through to the console. The portable's ID will go out when it keys up and the CDM's ID will go out when it dekeys.

Now I bet the next thing will be "but we want to use Pre-ID on the CDM!" Understandable. You need to make another channel with another MDC profile that uses post-ID. And the user would have to remember to switch to that channel. You could theoretically use the channel steering pins to do this automatically. You can program one of the accessory pins to autmatically steer the radio to another channel. Program it to go to that new channel with Post-ID. Take the same wire that goes active high to turn on the repeater to drive that channel steering accessory pin. Then when you turn on the repeater, it will automatically steer the radio to the post-ID channel.

[tmtu]

nmfire10, thanks for the helpful suggestions!

Here's the problem we're trying to overcome... the CAD requires PRE-MDC (not going to change at least for a few years). I was interested to know if the "trunking" option that is offered on the SVR-200 would overcome this.

From looking at the SVR200 docs, it looks like trunked CDM1250s are supported... would the pin-outs not be the same for conventional operation? Basically what I am suggesting, why can't the SVR-200 just wait until the tone clears!?!

Thanks!

[nmfire10]

The SVR's trunking functionality really has nothing to do with the tone or any other beeps and bonks. It looks to see if the mobile radio is transmitting for more than 250ms. It assumes that to mean the channel was granted. You have to click your portable. The SVR will wait to see if the mobile gets a channel. If it does, it will transmit a beep back to you and you can then key up and transmit again. It is not the most convinient thing and I feel it is too easy to screw up.

Honestly, you would be better off just making sure you wait 1/2 a second before transmitting on the portable. Here is another idea. Lets say your CDM is set for 400ms pre-time. Program your portables with a 400ms pre-time. Guess what, the CDM will simply ignore anything it gets from the SVR while it is in pre-time. The pretime will expire on the portable within a few milliseconds of the CDM's, they will be almost synchronized and it will prevent your users from clipping.