I should start by saying I am a soldering wizard. I have a TS22A manufactured by Harris. The main board in the body of the unit is date stamped in 1995. The board in the earpiece capsule is dated 1996. Upon finding my old unit in the closet, I found that both the 9 V battery and 3 V battery were toast. This is the version that only has one internal lithium cell on the main board. After acquiring a new cell and spot welding new nickel connections on to the 3V battery, I installed it along with a new 9 V battery. Following the replacement, I found that the loudspeaker would only pop when pressing it’s button, where it used to produce three different volume levels of hum when testing while disconnected from a phone line.

On further investigation I found that one of the chips on a daughter board in the earpiece capsule had it’s top sanded off to obscure its identity, and there was a paper label with the letter R attached to it. I know that some Harris TS22* units had a data lockout chip/processor that would seize up when the 3V battery died. I’m not sure if this is one of those units or not. I will be posting pictures of this chip soon. Can anyone here help me identify the chip, or tell me why these symptoms may be occurring? I know some companies offer a $65 service for repair of these units, but if I can get the offending chip (if it is the problem) and replace it myself, I would save a not insignificant amount of money. If anyone would be willing to help me I would be eternally grateful! I’ve had this unit since high school and would love to get it working.

Thank you in advance!
Garbleduser