Batboard

I can not get the COR function , Pin# 8 being used, to activate a relay. The relay is a 12 VDC ,pulls about 40 MA. COR is set to go low on received PL..

I also reversed the function so COR would go high on correct PL ,which is then connected to the base of a NPN switching transistor, still not operating. I noticed on the COR line, the voltage does not always swing to 5 VDC or 0 when a relay or NPN is attached.

Any suggestions?

Yep- use an optical or other solid-state relay that's triggered via ground. program pin 8 to COR-. Add a 200K resistor from 12v+ to the op relay's input. This will add a positive bias to ensure the relay shuts off when it should since some of these radios "leak ground" to the accessory pins when not active. This is also true on the CM radios. Works for me every time.

BTW, what are you doing that uses a relay that switches with COR?

I have a situation where a volunteer fire department is going to be paged over ther repeater by a county dipatch center. I have the CDM set up for QCII, however the county has a GE M II which will only do 1 PL tone. I do not want all the county traffic to come over this repeater. I am trying to set the CDM to open a relay on the QCII page and then let traffic pass. I am using a Zetron 37 Max for repeater operation. The QCII function will time out and then the repeater will not be open until it is reset again.

When you say "come over the repeater", do you mean that you don't want the county's other dispatches to come over your CDM when it isn't your call?

Yes

Set up pin 4 for your klaxon or other audio alert using (-) activation

Set up one of the acc. connector input pins for (-) activate to put the radio into CSQ (shuts off PL when lead is grounded)

Install an ELK960 or similar timer to trigger on ground activation.

Install a lead from pin 4 to the ELK timer's trigger lead.

Run the ELK's COMMON terminal to ground (pin 7)

Run the ELK's NO terminal to the pin that you assigned as CSQ enable.

Set the ELK to trigger when it sees a (-) signal. Set the ELK timer delay for the amount of time that you want the PL to be open.


When you receive a QCII call, pin 4 will go (-) and activate the klaxon (or whatever). At the same time, pin 4 will also trigger the ELK timer and begin its time sequence. The timer will ground your CSQ enable lead and force the PL open until the timer drops.

You can concievably kill two birds with one stone here and without any external relays, timers, or sirens. I've done this in my house and it works perfect (yes, I have station alert in my house). This will create a loud alert sound followed by dispatch radio audio that will stay open for preset time. This requires no external relays, triggers, timers, resistors, transistors, or flux capacitors. The radio does all of this on it's own out of the box.

Program the CDM as follows:

Radio Configuration Screen
Alert tones tab: Under volume, set it for constant boost and the offset for something like +40 or +50. This will make the alert tone much louder than the radio audio for the purpose of getting people's attention.


Conventional Personality Screen:
Basic Tab: Frequency and PL/DPL as normal. RX only unless you need it to TX.

Options Tab: And/Or muting

Signalling Tab: Quick-Call II-1, PL/DPL Required for data, AND squelch

Scan & Phone tabs: Disabled

Advaned Tab: De-Emphasis, exansion and non-standard reverse burst as needed.


Signalling Configuration

General Tab: Auto-Reset time. This is how long the audio will stay on after the call if you want it to shut off automatically. Max is 255 seconds. Personal experience is about 120 seconds but it's totally up to you. All the others in this tab are not used.

Call Tone Tag Tab: This is the alert tone that will blast over the speakers when the tones go off. I use Alert 6 but you can pick whatever you want by experimenting. Someone of them are dumb.

Emergency: Disabled


Quick-Call II System 1
Basic Tab: Format is whatever you use. If you use a single pair of tones to set it off, then just choose A/B. I'm assuming you know the ins and outs of QC-II to set this part up, too many variables to list here. All the other settings in this tab are not used.

Call Alert Tab: Call Alert with voice, Call alert LED, Alert tone auto reset all selected. Auto reset timer type should be "Auto w/o Carrier Override".

ID Tones Tab: Self explanitory, your tones.

Assign the channel to a zone, but obviously you know that already since you are using the radio to begin with.




Thats all there is to it for programming. Wire the external speaker leads through an audio balancing transformer so you don't toast anything and feed it into a PA system. Now you have this little radio sitting there being quiet and not saying a word. When the tones go off, it will beep you selected alert tone really loud to wake everyone up and then the dispatch radio audio will come over the speakers at whatever volume you have the radio set for.

Thank you, I will give it a try. Appears this should work.