Bearcat BC-248CLT

This is a pretty easy mod.  The connector on the back of the unit is hot garbage and no decent antenna will connect to it.  All I did was open the unit and desolder the existing connector.  Then I drilled a hole the size of my SO-239 connector.  I used one that had the four screw holes on it so that I could mount it to the plastic easily.  Slide the new connector in to the hole you just drilled, fasten it to the housing, and solder the center pin to the PCB.  Put it all back together and enjoy your new antenna connection.

Sometimes, you just need the raw audio from your radio before it gets mangled by processing.  Maybe you want to use it for a repeater or you want to decode data modes.  Whatever your reason may be, I hope this can be helpful.  

There are lots of pages with documentation out there about adding discriminator taps to scanners and radios.  The problem is that after an exhaustive search, I was unable to find any for this particular scanner.  The BC-248CLT either wasn't a common scanner or it just happened to not be owned by anyone that wanted to do this modification.  Lucky for me (and you) this scanner is similar enough to some other Bearcat scanners that we can grab a multi-meter and figure it out.

For this modification, you'll need a 10k resistor (small), 2.2nF capacitor (also small), a short piece of coax (thin), and a 3.5mm mono audio jack.

Find a place on the case to install the 3.5mm jack.  I chose to install it directly above the external speaker connection to make it look as stock as possible.  Drill a hole, mount the jack, and tighten it down.  Solder one end of the coax to the 3.5mm jack.

Now, we need to solder the resistor and capacitor to the PCB.  Locate IC101 as this is the discriminator chip.  Pin 9 is the unfiltered audio output.  Solder one side of the resistor to pin 9 on the IC.  I scraped away some of the solder mask on the trace leaving pin 9, but you can do it however works best for you.  The other side of the resistor goes to the capacitor. and the other side of the capacitor then can be soldered to the shield of coil right next to the IC.

Connect the center conductor of the coax to the junction between the resistor and the capacitor and the braided shield to the shield of the same coil you used for the capacitor.

Now you can close up the scanner and test your work.  If all went well, you will have a nice raw audio signal to use for whatever project you have going.