Powering XTL5000 without Ignition Sense wire connected to external +12 V?

[n6fnp]

I have a couple of mid-power XTL5000/XTL2500 radios that I am using in a base station configuration with an AC power
supply. I'm trying to keep the wiring to a minimal and would like to eliminate the need for the red ignition sense wire
that goes to pin 25 on the 26 pin J2 connector on the back of the radio. I have one 26 pin connector that internally has
pin 25 (ignition) connected to pin 24 (SW_B+). With one of the radios it powers up fine with this connector, but when
trying on a second radio, it doesn't power on. I can only get it to turn on if I use a cable that has the ignition pin 25 connected
directly to +12 V.

Is there something that needs to be changed on the radio so that it can use the SW_B+ line on pin 24 to satisfy the ignition sense?




-Thor

[Bill_G]

I'm not entirely positive where in XTL programming, but it does have a programmable ignition sense. It's a global function. So, expect it to be buried on one of the radio wide tabs. The one caveat I do know about XTL's is you have to have the Emergency jumper installed in the plug to get ignition ignore to work.

Why your plug worked on one radio makes no sense. It shouldn't have worked at all. The Switched B+ point is an accessory power point that turns on/off with the radio. ie: there should be nothing there to loop over to an ignition sense point to raise that line. It should be dead until the radio is turned on.

[Jim202]

I believe there are 3 different software settings that can be selected to determine how the radio powers up. One of them will turn the radio on and off with the ignition. Another needs the +12 volts on the ignition line plus pressing the power on in the control head. Can't remember what the third one was.

There is a chance the radio is programmed differently.

Been a while since I programmed that feature, so can't exactly recall just where the selection is.

Jim

[n6fnp]

Thanks for the info so far. I checked the radios. Both of them have the "Ignition Switch" setting set to "Blank" in the Radio Wide Advanced
section.

The way this setting is described is "Radio powers-on with a radio-user power button press" leads me to believe that if this setting is set to
"Blank" the radio should turn on when the power button is pressed, however, this is not the case with the radios I have. They need to have
+12 applied to the ignition sense line or won't turn on.

I've tried the J2 plug with pin 25 (ignition) connected to pin 24 (SW_B+) on three radios, all with the Ignition switch setting to Blank. Two
have O5 heads and seem to power up okay with it. The third one that doesn't power up with this plug has a W5 head.

[jackhackett]

That's the old 'Spectra' style head, correct?
I believe that on those, like the Spectras, you must connect the ignition wire.
The installation manual says for on/off operation independent of ignition switch, to connect it to "battery hot" at the vehicle fuse block.

For a base station connect it to power supply positive terminal.

That's the proper way to do it, so do it that way.

EDIT: make sure you properly fuse the lead as well.

[Will]

There is a fix for the W4, 5 and 7 series control heads. Move one jumper and add a resistor where the jumper was removed.

[fineshot1]

Thanks for the info so far. I checked the radios. Both of them have the "Ignition Switch" setting set to "Blank" in the Radio Wide Advanced
section.

The way this setting is described is "Radio powers-on with a radio-user power button press" leads me to believe that if this setting is set to
"Blank" the radio should turn on when the power button is pressed, however, this is not the case with the radios I have. They need to have
+12 applied to the ignition sense line or won't turn on.

I've tried the J2 plug with pin 25 (ignition) connected to pin 24 (SW_B+) on three radios, all with the Ignition switch setting to Blank. Two
have O5 heads and seem to power up okay with it. The third one that doesn't power up with this plug has a W5 head.

This is the way i have always done it and it
works every time.

CPS Ignition switch setting to "Soft Power OFF".

Main power plug connector 20A fused to +12V hot all the time.
Leave pin 24 out of it with no connection.

Use the power ON/OFF button on the control head to
actually power on and off or you can hook up 3A fused +12V
hot to Acc pin 25 via a toggle switch and use the
switch to turn the radio on and off.

It should be noted that if your radio has a trunk system
programmed into it without the use of the ignition switch
sense or manual power off button on CH there may not be
any de-affiliation before powering off.