Expanding Caller ID Storage

by Datum Fluvius

The telephone company sent you this tiny little 25-call memory Caller ID box for free in the mail when you signed up for Caller ID.  You want a better box with more memory, but the $59.95 your phone company wants for a 99-call box just might be better spent on something else.  Like the extra charges for having Caller ID!  Hmmm...  What to do?

Easy... just hack it!

The two units I'm reviewing are both called CIDCO Model PA.

These units use the same software, CAI version 4.1, which they proudly display when they first wake up.  The difference is in the hardware.  You can find the PC board revision letter on the sticker inside the battery compartment, at the extreme lower-left corner of the sticker like this: J4.1

Don't worry if yours is different than mine.  Just read the procedure and I think you will catch on to CIDCO's method of selecting the memory capacity for a given unit.

Assembly 553, Revision "E"
Assembled 1997

The memory capacity jumpers are on the battery side of the PC board on the left side.  You don't have to unscrew the PC board from the faceplate and LCD screen.  Yay!

When jumper "C" is closed, the capacity is 25 calls.

Open the solder jumper with a sharp X-Acto knife or soldering iron and the device should wake up and display: 99 calls, CAI Version 4.1

This jumper is especially easy to spot because the poor factory slave who soldered the thing dabbed the nearby pads ("D" and "B") with red epoxy to avoid any spillover.  Her job was later designed out of the process, however.  (She's picking up cans in your alley as you read this.)

Assembly 553, Revision "J"
Assembled 1998

The memory capacity jumper is a single pair of pads, marked "C", and is very hard to spot.

First, you will have to unscrew the PC board from the faceplate in order to look for the jumper (4 screws, one in between the jacks).  The jumper is just to the right of the big black blob of chip epoxy, above the "C12" capacitor.  It looks like an unused capacitor pad.  A very careful and sharp X-Acto knife is more useful here than a cheap soldering iron!

Just like the "Revision E" model, this jumper is closed when set to 25-call capacity.  Open it up, and you have 99.

The other capacity (and most program/test) options are missing.  Apparently not many folks bought the mid-range units...

That reminds me - what the hell are those program/test pads for?  What could we find out by using them?  They are present on the "Revision E," so it might be hard to go out and order a test unit now, but any older unit should work...

The "Revision E" pads are labeled, in order from top-left:

K3 (???) EN (Enable?) -TST (Test?) -LD (Load?) D (Capacity Jumper) C (Capacity Jumper for 25 Calls) B (Capacity Jumper) A (Capacity Jumper) RS (Reset?)

There are some similar pads on the "Revision J" but they are labeled:

HKT (Jumper - Open) -LD (Load?) C (Capacity Jumper for 25 Calls)

I have not tried out anything on these.  Anyone for some exploration?