Description
Siemens TMDC Card S30810-Q175-X 42521 MFG 58028 PBX Telecom Board
The Siemens TMDC Card S30810-Q175-X is a plug-in PCB module for Siemens PBX and telecom switching systems. Identified by assembly number 42521 and manufacturing number MFG 58028, this card provides timing and digital control functions within its host system. It features an on-board Dr. Steeg & Reuter voltage-controlled crystal oscillator (VCXO) module rated at 16.384 MHz — a frequency standard closely associated with ISDN and digital telecom timing architectures.
Specifications & What's Included
- Manufacturer: Siemens
- Card Type: TMDC (Telecom / PBX plug-in module)
- Primary Part Number: S30810-Q175-X
- Assembly Number: 42521
- Manufacturing Number: MFG 58028
- On-board VCXO Oscillator: Dr. Steeg & Reuter V30141-Z44-F5-Rev2
- Oscillator Frequency: 16.384 MHz
- Oscillator Date Code: 91/22
- On-board Connector: BNC (single, mounted vertically on PCB)
- Bus Interface: Gold-finger edge connectors (dual, top and bottom edges)
- Status Indicators: ACT (green LED) and ALM (red LED) on front-panel faceplate
- Notable ICs: SN74LS151N (Texas Instruments, visible on PCB); additional TTL logic ICs throughout
- PCB: Green, full-length card format
- Included: Card only — no additional accessories or cables
Applications
The Siemens TMDC card is designed for use in Siemens enterprise PBX and digital telecom switching platforms, where plug-in cards provide specialized timing, signaling, control, or interface functions within a card-cage chassis. Siemens produced a broad range of such modular telephony systems — including the EWSD digital exchange and the Hicom PBX family — from the 1980s through the 2000s, and plug-in modules like this one are the core building blocks of those architectures. The 16.384 MHz VCXO frequency is a standard clock reference in ISDN and E1/T1 digital telecom equipment, placing this card firmly in that generation of digital switching hardware. Cards of this type are typically sought today by organizations maintaining legacy Siemens PBX or switching systems, telecom repair technicians, and surplus electronics buyers sourcing hard-to-find replacement modules.
This Siemens TMDC Card S30810-Q175-X (42521 / MFG 58028) PBX telecom board has been inspected and appears to be in good condition. The PCB is clean and intact with no visible damage to the board, traces, or components. The on-board Dr. Steeg & Reuter VCXO oscillator module (V30141-Z44-F5-Rev2, 16.384 MHz) is present and undamaged. The front-panel faceplate with ACT and ALM LED indicators is intact. Gold-finger edge connectors show normal contact wear consistent with prior installation. Please view our photo set and contact us if you have any questions.
Warranty Information
Additional Information
Brand: |
Siemens |
Model: |
TMDC Card 42521 |
MPN: |
S30810-Q175-X |
Secondary Model: |
MFG 58028 |
Type: |
PBX Telecom Card / Module |
SKU: |
41683 |
Condition: |
Used – Inspected and in Good Condition |
Seller Notes: |
Card only; no additional accessories included. |
Country/Region of Manufacture: |
Germany |
Form Factor: |
Card / Module (PCB) |
VCXO Oscillator: |
16.384 MHz (Dr. Steeg & Reuter V30141-Z44-F5-Rev2) |
Oscillator Module: |
Dr. Steeg & Reuter V30141-Z44-F5-Rev2 |
Oscillator Frequency: |
16.384 MHz |
Date Code: |
91/22 |
Connector Type: |
BNC (on-board), Gold-finger edge connectors |
Status Indicators: |
ACT (green LED), ALM (red LED) |
Compatible With: |
Siemens PBX / Telecom Switching Systems |
PCB Color: |
Green |
Condition Notes: |
Siemens TMDC Card S30810-Q175-X (42521 / MFG 58028) inspected and in good condition. PCB clean, VCXO oscillator present, edge connectors show normal wear. Please contact us with questions. |
