CDM 1550 ls+ and Pyramid SVR 250

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Post Reply
User avatar
rrfd43
Posts: 434
Joined: Wed Mar 06, 2002 4:00 pm
What radios do you own?: Cobra 25 LTD Classic with echo

CDM 1550 ls+ and Pyramid SVR 250

Post by rrfd43 »

We have gotten these systems installed and now I have to deal with implementation. I did not spec. them so I have had little input up until now. They are all used in a fire department application. I have come up with a few questions:

1. When the portable transmitts and then the CDM repeats it we of course get two MDC's: one the portable then the rig mobile. We still need both to identify so I really just can't deprogram one. Is there any way to inhibit the MDC on remote mic/ptt from the CDM? I have not found one but figured I would ask.

2. The repeater gives the priority tone every few seconds and although important for operation it is distracting on calls. Is there any DOS setting changes that would eliminate this? Or is this not the use for the DOS settings?

3. Does the CDM provide enough current on the rear active high setting for "control" toggle to also power a relay to light and "on" indicator light in the cab? Anyone have a spec on what this is capable of?

Do you have any other comments on utilizing these systems that could help me out?
User avatar
Josh
Posts: 1931
Joined: Mon Sep 03, 2001 4:00 pm
What radios do you own?: APX4K, XTL5K, NX5200, NX700HK

Re: CDM 1550 ls+ and Pyramid SVR 250

Post by Josh »

I have an SVR200 connected to my CDM1550LS+ out in the car.

My unit only sends out the tone when it's turned on and that's it. I don't understand what yours is doing. Isn't the SVR250 at 16 or so channel version?

For MDC, there really isn't anything you can do except have two MDC-IDs. I suppose it could be possible to program another mode in the radio for use specifically when at the scene which has the MDC PTT-ID disabled.

As for the relay/light thing.... I can see how a light might be important, but how are you controlling the on/off function of the SVR? I was able to program a button on the radio, I think the aux outputs to ground the line when turned on. I aliased it to say- in my case "PAC-RT ON" and "PAC-RT OFF" on the radio's display when the button is pushed. an MDC Call packet can also turn this function off and on from a radio on the CDM's frequency.

So far it's worked great and I'm a big fan.
User avatar
rrfd43
Posts: 434
Joined: Wed Mar 06, 2002 4:00 pm
What radios do you own?: Cobra 25 LTD Classic with echo

Re: CDM 1550 ls+ and Pyramid SVR 250

Post by rrfd43 »

The SVR 250 is just the next model up. Has something like 16 channels.

The tone you talk about is what I'm talking about. Though it gives you two important indications: the unit is on and you are in range, but it is annoying when operating. I was able to increase the unmute time on my mt2000 to 300 milliseconds and this cuts it completely out. I see the light flash for channel activity, but that is it. We will be running HT1000's and MT1500's with them. I'm 99% sure I can't delay the unmute on the HT1000's and I am not sure yet about the MT1500's.

For the light we use a front pannel button and use the control 1 on and off setting. I note that it goes active high, so I should find 12 volts on the pin. I was thinking about getting a small led marker light with flasher and control it with a relay. This way at the most basic level the users should be able to know if the unit is turned on or off.

So far we need to tune some audio quality issues out, and then write an SOP for operation.
User avatar
IMBEJames
Posts: 132
Joined: Wed Nov 02, 2005 5:05 pm

Re: CDM 1550 ls+ and Pyramid SVR 250

Post by IMBEJames »

Check your connections to the SVR and make sure it is staying on (ie, no intermittent power/ground or trigger). The only time it should transmit a lock tone is when it is activated (which should always be AT the scene, by the way). If the SVR's transmit a lock tone more than once, the priority counters in the other ones that receive the tone will be off; if the lock tone is transmitted out of Rx range of the other repeaters, the hierarchy will get screwed up.

Without having the specs in front of me, the CDM will give you enough current to power a relay coil. I wouldnt recommend much more than that.

As far as the MDC goes, if you don't need both radios (mobile and portable) to transmit MDC, you can always set up a personality with no MDC in the mobile. You can program an accessory pin for channel select, and use a switch to pull that pin low (ground). That will steer the radio to that channel, but you can also use the same switch as a ground activation for the SVR. So one switch does it all in that case.

If you need both radios to transmit MDC, you can always set up either the mobiles or the portables (I'd do the portables) to transmit post-MDC. That way anyone with reverse-aliasing (other Pro-series users or console operators, for example) will see one id during the transmission, and at the end will see the other id.

Just some thoughts.

-jamie
James Eslinger

York, Maine
Batwings21
Posts: 930
Joined: Fri Jun 23, 2006 11:21 am

Re: CDM 1550 ls+ and Pyramid SVR 250

Post by Batwings21 »

Just a thought, If you are going to use the aux output to control a replay, I would recommend putting a diode in reverse polarity across the relay to soak up the voltage spike produced by the magnetic field falling through the coil of the relay. Might just save you a trip to the depot.
Post Reply

Return to “General Motorola Solutions & Legacy Radio Discussion”