The XTS series have a Universal Crypto Module (UCM) and Keyboard/option board combo. Normally without hardware crypto, they will have the keyboard only option board, and the part numbers vary base on the model type (1.5,2,3).

Model Matrix

XTS2500 Keypads
P/N	TYPE	Model	BackLight	Description
0104018J69	1.5	Keypad	Bright	Motorola Part from Service Manual, no crypto
7585776C02	2	Keypad	Bright	Motorola Part from Service Manual, no crypto
7585776C01	3	Keypad	Bright	Motorola Part from Service Manual, no crypto
0104020J49	1.5	Kit, FM	Bright	This is a listed accessory kit
0104020J50	2	Kit, FM	Bright	This is a listed accessory kit
0104020J51	3	Kit, FM	Bright	This is a listed accessory kit
0104024J45	1.5	Unknown	Bright	5 Algo, From an eBay auction
0104024J44	2?	Unknown	Bright	Never seen this, inferred as model 2
0104020J51	3	Unknown	Bright	5 Algo, From an eBay auction
0104027J01	1.5?	US Military	Dim	Never seen this, inferred as model 1.5 Night Vision
0104025J11	2?	US Military	DIM	Never seen this, inferred as model 2 Night Vision
0104025J12	3	US Military	Dim	AES only, Night Vision, from a Facebook seller

The above crypto parts are listed in the "Security Policy:Astro Subscriber UCM" Guide. Some part descriptions are a inference on my part as I've not seen them, they are designated with a ?. If something is wrong, please update it.

It's my understanding any of the UCM's can do any algorithms, they just need to be programed via a KVL3000+ or later keyloader.

The different model UCM's are the same, but lacking the Snaptron keys and polyester tape to hold them in. The LED's are missing in the 1.5 version as well, but the dropping resistors are present. This is due to the backlight for the LCD being sourced from the keypad. The CPU will simply tell the Keypad backlight on, and the keypad will take care of the rest.

Note the dim listed parts are for use with night vision, and will appear to be not working in daylight and barely visible at night. I've experimented with these and have reverse engineered a better soultion below.

Pictures of UCM's

0104025J12 back
0104024J45 Front
XTS2500 LCD module
7585776C01 Back
XTS2500 LCD connector
XTS2500 0104025J12 DIM UCM 5v regulator

Modification of Dim to Normal

There are a few UCM boards made for night vision equipment, and I reversed how to make these brighter by studying a couple good boards. It's basically some current limiting resistors and a regulator. In the dim UCM there is an addition of a 5v regulator which powers the LEDs rather than being powered via the B+ voltage of 7.5 volts.

I've reverse engineered the partial diagram of the dim UCM below. It's also available as a pdf.

UCM LED diagram

First the MAX1615 5v regulator needs to be removed and jumpered out. This will put B+ (7.5v) on the LED's vs 5v.

The following resistors need to be changed, note they are 0402 size parts:

LED resistors
Number	Dim	Bright
R18	560	330
R27	560	330
R63	560	330
R45	560	330
R9	6800	560
R10	6800	560
R11	6800	560
R12	6800	560

I've experimented and most of the improvement comes from changing the LCD resistors (R9-R12). The difference of the limiting resistors on the keypad LED's is not as noticeable as the 5 to 7.5v on them.