sending radio check with MC2500

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eboe
Posts: 317
Joined: Thu Sep 18, 2003 7:12 am

sending radio check with MC2500

Post by eboe »

ok, i got my mc2500 up and running as far as transmit and receive of voice. now i'm trying to program it to do some of the more advanced features such as radio check, radio disable, radio enable, etc.

i started by trying a radio check. i set up one of the function buttons for manual paging and defined it as radio check. i have a sample ptt id programmed in the ptt aliases (not sure if that's even needed) and i seem to be doing everything ok with the button programming.

ie: the mc2500 goes into the proper mode and the cdm1550 that it's connected to is transmitting.
the ex600xls that i'm trying to do the radio check on is receiving the ptt id of 9999 from the deskset.
the ex600xls doesn't ack so the mc2500 is retrying.
the mc2500 retries like 5-6 times and then displays "no-ack"

i'm not sure if the mc2500 is sending the radio check properly or if the ex600xls is just not sending an ack.

i've looked through the cps for the ex600xls and i'm not sure if there is an option to enable or change the way it sends an ack that would affect this

i've also looked through the rss for the mc2500 and i'm at a total loss when it comes to the page for the "stat alert setup"

there are options there for leading, trailing, no ptt id, silent, bit-sync, leading pre-time, trailing pre-time, etc.

i'm not familiar with this type of programming and i could use a little guidance.

thanks
"In the beginning of a change, the patriot is a scarce and brave man, hated and scorned. When his cause succeeds however, the timid join him, for then it costs nothing to be a patriot." - Mark Twain
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HumHead
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Post by HumHead »

Due to the key-up delay in the tone remote system and radio, the front part of the signaling packet may be getting clipped off. As a result, the radio will not decode it and, therefore, doesn't see anything to acknowledge.

If you are transmitting through a repeater, that will further increase the delay before audio is actually passed.

Try increasing the leading pre-time to around 300-400msec and see what happens. If you want, start with 700-800msec, and then step it down until you find the point where it becomes unreliable in your system.
eboe
Posts: 317
Joined: Thu Sep 18, 2003 7:12 am

Post by eboe »

i tried what you said with 1000ms on the leading pre-time and i was using a simplex channel so repeater delay was not an issue. it still didn't work. deskset kept re-trying, no ack from the ex600. i must be doing something else wrong.
"In the beginning of a change, the patriot is a scarce and brave man, hated and scorned. When his cause succeeds however, the timid join him, for then it costs nothing to be a patriot." - Mark Twain
MassFD
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Post by MassFD »

On the EX-600 the MDC RX needs to be turned on, there is also a field in the EX that sets how long it waits to ACK the radio check. It needs to be at least 750ms or the console may not hear it for the following reasons

(1) The console has to unkey the Xmitter and some tone remote adapters have a drop out delay.
(2) The simplex radio (base) needs to unkey and enable it's receiver
(3) The simplex radio (base) needs to detect the PL or DPL code to unmute the receiver and pass the audio to the console.

All 3 combined can add up to 600ms so the console never hears the ACK

I have never been able to make this work reliably due to the delays without forcing the base to CSQ for 5 seconds after XMIT by making a mod to the tone remote adapter.

Radio Check always works right out of the box on a 4 wire duplex base but it can give you nothing but trouble on simplex.
Cause Motorola said so that's why
eboe
Posts: 317
Joined: Thu Sep 18, 2003 7:12 am

Post by eboe »

ok i tried it with the ex600 having an ack pre-time of 850ms and still nothing. how can i tell if the radio check is even being received by the ex600? and how can i tell if the ex600 is even trying to send an ack? will the ex's red x-mit led light up when it sends an ack? ...cuz it's not. the ex is however programmed to receive, decode and display mdc id's. i'm assuming that's enough to make it capable of receiving other types of mdc packets, correct? i'm stumped. again. lol
"In the beginning of a change, the patriot is a scarce and brave man, hated and scorned. When his cause succeeds however, the timid join him, for then it costs nothing to be a patriot." - Mark Twain
MassFD
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Post by MassFD »

There is also a field in the EX 600 (a check box) to enable radio check. I do not have the CPS in front of me but I think it is in one of the tabbed menus. As I remember, the Xmit LED on the EX does come on when it ACK's.

Can you monitor the freq with another radio in CSQ, you should hear the console MDC followed by the 800ms delay you set then the EX ACK.

Console Quack - 800ms delay- EX 600 Quack

If you do not here both the EX is not responding, if you do then either the TX to RX turn around time is preventing the console from hearing the ACK or the console is not decoding it.

Can you listen to the console wireline and hear both Quacks?
Cause Motorola said so that's why
eboe
Posts: 317
Joined: Thu Sep 18, 2003 7:12 am

Post by eboe »

ok, i'll give a listen on another radio on CSQ this afternoon when i get back to the office., that's easy. i'll have to see if i can tap into the wireline with an external speaker to see what's going on there.

on a side note, how hard would it be to set this up as a 4-wire duplex system with 2 CDM's and a duplexer? do i need a RICK too or not? i don't have the funds in the budget for an MTR or any other kind of base, but i have a few CDM750's around if i can use that (for the receive side maybe?) or if not i can get another 1550 without too much trouble.

does anybody have any codeplugs that i could "take a look at" to get me on the right track here?
"In the beginning of a change, the patriot is a scarce and brave man, hated and scorned. When his cause succeeds however, the timid join him, for then it costs nothing to be a patriot." - Mark Twain
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