Hacking Caller ID Boxes

Because the Caller ID system uses out-of-band signaling that is set up in the 5ESS switch, there is no way to "fake" your out-calling number unless you make an opera-tor assisted call, or dial through a company PBX.

You can, however, hack the box that sits in your house up to more than eight times its capacity if you have the right revision!

Here's how you do it:

Most Caller ID boxes you see in stores are sold according to the capacity of numbers they can store.  The more you pay for the box, the greater storage capacity of numbers (between 60 and 99 for example) you obtain over the cheaper boxes which only hold between 10 and 30 numbers.

CIDCO, or Caller ID Company, is one of the most popular manufacturers of Caller ID hardware, and is publicly traded on the stock market.   CIDCO's boxes are sold in stores under names such as AT&T, GTE, RadioShack, and others.

Because CIDCO concentrates on mass production and OEM sales, it is less expensive to manufacture one Caller ID circuit board that is "jumper" (solder points instead of jumper pins) selectable for the capacity of numbers that it can store.  The good news is you can buy the cheapest CIDCO Caller ID box that you can find (10 number memory is perfect) and upgrade it to handle 85 numbers!

How to Buy It

Before you buy, it's important to know first that you have a CIDCO unit (remember, lots of companies show their names on the outside of the case) and which ROM revision you have.  Fortunately for us, the CIDCO engineers tell us this when the unit is "booting up."  When you insert the nine volt battery, watch the display.  You will see: C-NAM ver 1.2A or C-NAM ver 1.4

After this, you will see the capacity of the unit.  If it is a "10-call" or "30-call" unit, buy it as it should be very inexpensive.  If it is a 60 number unit, you can now make it hold 25 additional numbers.  If it says "85 call", it is maxed out and you cannot increase the storage.

How to Hack It

So your unit says 1.2A or 1.4 when you power it up, and you saved tons of money by purchasing the 10 number version.

Get out your Phillips screwdriver and take out the two visible screws on the bottom of the unit.  Peel off the rubber feet on the opposite side of the two screws you just removed and you will find two additional screws (total of four) that will let you open the box (just peel the feet off and save them).

Now we can see the circuit board.  In the offset in the middle side of the board you will see a GoldStar chip with the number GSN15 GM76C28AFW-10 or something similar.  Beside it you will see one of two jumper pads depending on the ROM version you have.

The two versions are as follows:

Version 1.2A - One pad unlabeled with four solder points.  A blue trace wire from the GoldStar chip to:

A 10 number Eng/Spanish B 85 number Eng/Spanish C 10 number Eng/Spanish D 10 number Eng/Spanish

Version 1.4 - Two sections labeled:

X2 C oo 10 Call B oo 30 Call A oo 60 Call (none) 85 Call

R17 D oo French/English E oo Spanish/English F oo English Only

With Version 1.2A you must solder the trace wire from the GoldStar chip to the "separated" gold pad on the circuit board that is labeled "B" to obtain full capacity of 85 numbers.

With Version 1.4 you will need to remove the solder that is "bridged" between the circuit board pads (labeled as "o" above) to increase the capacity.  You will most likely have solder "bridged" between the A, B, or C pads.

Your language will most likely be jumpered between the pads labeled E which lets you select English or Spanish after boot-up.  If you want to force English, or allow French and English, just remove the bridge from pad E and span the pads between D or F with solder.

That's all there is to it!

As new Caller ID/Call Waiting (displays who is calling you while you're on call waiting) boxes come out, I'll have a fix for those as well (most store 99 numbers initially).  I've hacked around with half a dozen different boxes and CIDCO's are the best.

Others like TT Systems will only change button features when you cut traces instead of increasing capacity, so it's no use explaining those.  If you have a different CIDCO ROM revision or another Caller ID box, look for a jumper pad, or solder points!

Chances are you might be able to hack it in the same manner that we can with these!