Tandy 1000 RLX/B (250-1452B/53B)       Memory            Faxback Doc. # 1344

512K ZIP kit
    √25-1083 consists of four ZIP chips.  This product is available
       from Tandy National Parts.

√ = Discontinued Radio Shack product
┌─────────────────────────────────────────────────┐
│ Tandy 1000 RLX/B (25-1452) - Expand from 512K:  │
├─────────┬───────────────────────────────────────┤
│         │    Add to the Main Logic Board        │
├─────────┼───────────────────────────────────────┤
│ 1MB     │        25-1083                        │
├─────────┴───────────────────────────────────────┤
│ The 1000 RLXB/HD came with 1MB of memory and    │
│  cannot be expanded further.                    │
└─────────────────────────────────────────────────┘


Before you can add memory to your Tandy 1000 RLXB, you will need the 
512 KB Memory Upgrade kit (25-1083). To install the additional chips, be
sure to read the instructions that come with the kit and the following
steps:

*CAUTION: Be sure to touch a grounded metal object before handling the 
memory chips.

1. Remove one of the memory chips from the special anti-static package.
2. Find the beveled edge on one of the chips.
3. Find the four memory sockets on the system board. These sockets are
   labeled U2, U4, U5, and U9.  Note the "1" on the end
   of each of the system board's memory sockets.
4. Line up the beveled edge of one of the chips with the "1"
   on the end of a memory socket.
5. Gently press the memory chip into the socket.
6. Repeat Steps 1-5 to install the remaining three memory chips.

Note: Be careful to never bend the pins of a chip!

Main Logic Board Layout:

   ┌─┬──┬─┬──┬─┬──┬─┬──┬───┬┴┴┬──┬─┬──┬─┬──┬────┬──┐
   │ └──┘ └──┘ └──┘ └──┘   └──┘  └─┘  └─┘  └────┘  │
   │ ┌──┐                  E14 o                   │
   │ │  │                  E13 o        o E17      │
   │ │  │                  E12 o        o E16      │
   │ │  │   ┌─────────────┐             o E15      │
   │ │  │   └─────────────┘    ┌───────┐      o E11│
   │ │  │    Printer           └───────┘      o E10│
   │ │  │    Connector         Serial         o E9 │
   │ │  │                      Connector           │
   │ │  │                                          │
   │ │  │<─Expansion         E6 o                  │
   │ │  │  Board             E5 o                  │
   │ │  │  Connector         E4 o             o E8 │
   │ └──┘                                     o E7 │
   │                                               │
   │                                               │
   │       ┌─Battery                               │
   │     ┌────┐                     E3 o           │
   │     │    │┌───────┐─┐          E2 o           │
   │     └────┘├───────┤ │Memory    E1 o           │
   │           ├───────┤ │Upgrade                  │
   │           ├───────┤ │Sockets                  │
   │           └───────┘─┘                         │
   │ ┌────────────────┐      ┌────────────┐        │
   │ └────────────────┘      └────────────┘        │
   └───────────────────────────────────────────────┘

(rjs-06/28/93)