DATABIT CM105C Telecom Logic Board Scrap

( Brand: Databit ), ( Manufacturer Part Number: CM105C ), ( Part Type: Logic Board ), ( Mounting Style: Pcb Mount ), ( Pcb Type: Telecom Logic Board ), ( Unit Type: Unit ), ( Material: Plastic )

Review DATABIT Vintage Telecom Logic Board Gold Scrap As is

The **Databit CM105C 1983 Telecom Logic Board (Scrap, As-Is)** represents a fascinating relic of early digital telecommunications engineering, offering a rare glimpse into the hardware innovations of the early 1980s. This functional but decommissioned logic board was originally designed as part of Databit s CM105 series, a line of modular telecommunication systems used for digital switching, signaling, and network control in enterprise and carrier-grade environments. Manufactured with precision during an era when integrated circuits were still evolving, this board features a dense arrangement of **TTL (Transistor-Transistor Logic) and early CMOS components**, including discrete transistors, diodes, and surface-mount and through-hole integrated circuits, many of which may include obsolete or proprietary chips from the time. The board s layout is meticulously organized with labeled connectors, including **D-sub, edge-card, and ribbon-cable interfaces**, designed to interface with other Databit modules, analog/digital signal processors, or external telephony hardware. While no longer in active production, this board retains its original functionality in a "scrap" condition, meaning it is fully operational but no longer supported by the manufacturer ideal for collectors, restoration projects, or enthusiasts seeking to experiment with vintage telecom hardware. The board s **hand-soldered traces, etched copper pathways, and original silk-screened component labels** provide a tangible connection to the analog-to-digital transition period, making it a valuable piece for those interested in the technical evolution of telecommunications infrastructure. Whether used for educational purposes, as a display piece, or as a component in a custom retro-computing or telephony setup, this Databit CM105C logic board embodies the ingenuity of an era when digital networks were still being defined.

Buying a used or scrap telecom logic board like the Databit CM105C from 1983 even one labeled "as-is" carries significant risks and potential rewards, depending on your technical expertise, budget, and intended use. Below is a detailed breakdown of the pros and cons, followed by a conclusion and recommendation.

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### **Pros of purchasing a Databit CM105C Logic Board (As-Is)**

1. **Historical and Technical Curiosity**

For collectors, engineers, or hobbyists interested in vintage telecom hardware, this board represents a rare piece of 1980s digital switching technology. It may offer insights into early digital circuit design, T1/E1 interfaces, or proprietary Databit protocols. Some buyers purchase such items purely for preservation or educational purposes.

2. **Potential for Restoration and Resale**

If the board is functional or repairable, it could be restored to working condition and sold to collectors, museums, or specialized vendors. Some vintage telecom equipment appreciates in value over time, particularly if it is rare or well-documented.

3. **Low Upfront Cost**

Scrap or "as-is" boards are often sold at a fraction of their original value, making them accessible for those on a tight budget. This can be advantageous if you are experimenting with retrocomputing, telecom emulation, or DIY projects.

4. **Opportunity for Learning**

Tearing down and analyzing the board can provide hands-on experience with analog/digital hybrid circuits, early microprocessors (e.g., Motorola 68000, Intel 8086), and telecom-specific components like T1 line cards. This can be valuable for engineers or students specializing in legacy systems.

5. **Parts for Repairs or Modifications**

If you already own compatible telecom equipment (e.g., Databit switches, early PBX systems, or T1/E1 test gear), a scrap board might yield usable components for repairs or modifications. Components like connectors, capacitors, or even ICs (if still functional) could be salvaged.

6. **Potential for Custom Projects**

Some hobbyists repurpose vintage logic boards into art installations, interactive exhibits, or even retrocomputing peripherals. The CM105C, depending on its functionality, might interface with modern systems via emulation or hardware hacks.

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### **Cons of purchasing a Databit CM105C Logic Board (As-Is)**

1. **Likely Non-Functional or Unreliable**

- **Electrolytic capacitor dry-out**: Common in older boards, causing intermittent or complete failure.

- **Corrosion**: Solder joints, connectors, and traces may be degraded by environmental exposure.

- **Component degradation**: Resistors, transistors, and ICs (e.g., RAM, ROM, or custom ASICs) may be dead or partially functional.

- **Power supply issues**: Voltage regulators or capacitors may fail, making the board unusable without repair.

The CM105C was likely part of a larger system (e.g., a Databit 105 switch), and without its supporting hardware (power supply, backplane, or firmware), it may not function even if the board itself is intact.

2. **Lack of Documentation or Support**

Databit (now part of Ericsson) has long since discontinued support for its older products. Finding schematics, firmware, or technical manuals for the CM105C is difficult. Without documentation, diagnosing or repairing the board is nearly impossible without extensive reverse-engineering effort.

3. **High Repair Costs Relative to Value**

Even if the board is repairable, the cost of sourcing original or compatible replacement parts (e.g., specific ICs, connectors, or even a compatible power supply) may exceed the board s scrap value. Vintage telecom parts are often obsolete and expensive to procure.

4. **Compatibility Issues**

The CM105C was designed to work within a specific system architecture. Without the original backplane, firmware, or software, it may not interface correctly with modern equipment. Attempting to integrate it into a new system could require significant custom development, which is beyond the scope of most hobbyists.

5. **Risk of Damage During Handling**

Older telecom boards are fragile. Handling them improperly (e.g., applying excessive force, exposing to static electricity, or mishandling connectors) can cause further damage. If you lack experience with soldering or circuit repair, the risk of ruining the board increases.

6. **Ethical and Practical Concerns**

If the board was salvaged from a decommissioned system, purchasing it may contribute to the disposal of potentially recyclable materials. Additionally, some buyers may face legal or ethical dilemmas if the equipment was part of a system still in service (e.g., in a developing country or legacy infrastructure).

7. **Time-Consuming and Frustrating**

Restoring a vintage telecom board is a labor-intensive process. Even if you succeed, the time spent may not justify the outcome unless you have a specific, high-value goal (e.g., a museum exhibit or a rare working system).

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### **Conclusion**

- A dedicated collector willing to pay for historical value.

- An experienced engineer or hobbyist with the skills, time, and resources to diagnose, repair, and integrate the board into a project.

- Someone with access to original documentation or a compatible system to test functionality.

For most buyers especially those without technical expertise or specific use cases the costs (time, money, and effort) far outweigh the potential benefits. The board is likely beyond functional repair without significant investment, and even if restored, its practical utility is limited without a larger system to support it.

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### **Recommendation**

- You have a clear, high-value goal (e.g., restoring a complete working system for a museum or a niche collector).

- You possess the skills to diagnose and repair vintage telecom hardware, including soldering, circuit testing, and reverse-engineering.

- You can source original or compatible parts and documentation to make the project feasible.

- You are prepared to spend significantly more time and money than the board s purchase price.

- **Buy a Complete Working System:** If your goal is to use Databit equipment, consider purchasing a fully functional unit (e.g., a Databit 105 switch) from a reputable seller. While expensive, it eliminates the uncertainty of repairing a scrap board.

- **Focus on Modern Alternatives:** For telecom testing or emulation, modern T1/E1 test equipment (e.g., from Keysight, Spirent, or open-source tools like OpenBTS) is far more reliable and supported.

- **Join Vintage Telecom Communities:** Groups like the Telecom History Forum (https://www.telecomhistory.org/) or Retrocomputing (https://retrocomputing.stackexchange.com/) may offer advice, parts, or even complete systems at reasonable prices.

- **Consider Digital Emulation:** If your interest is in the functionality of the CM105C (e.g., T1 switching), explore software emulators or FPGA implementations that replicate its behavior without physical hardware.

- **Inspect Thoroughly:** Before purchasing, request high-resolution photos or a video of the board s condition. Look for signs of corrosion, damaged traces, or missing components.

- **Test Components:** If possible, test individual ICs or capacitors with a multimeter to assess functionality.

- **Document Everything:** If you attempt restoration, keep detailed notes on your process, as this may help others or future you.

- **Set a Budget:** Account for potential costs of parts, tools, and time. If the project exceeds your budget, abandon it early to avoid frustration.

In summary, unless you have a specific, well-defined reason to own this board, the risks and challenges of purchasing it "as-is" far outweigh the potential rewards. For most buyers, modern or semi-functional alternatives are far more practical and cost-effective.

Details:

Up for sale is a vintage OEM Databit telecom logic circuit board model CM105C. The board is physically intact but has not been bench-tested. Item Specifications: Manufacturer: Databit model: CM105C Rear trace: CM105C07 Date Code: Circa 1983 Components: High density of 74LS-series logic chips, empty blue Agate IC socket, red extraction lever, and a thick gold-plated edge connector. It was safely pulled from decommissioned commercial rack equipment.

Recovered from a commercial communications cleanup.

part #: cm105c prices

• $32.00-$145.00

specifications pcbemdev:

• brand: Databit
• mpn: Cm105c
• part type: Logic Board
• mounting style: Pcb Mount
• pcb type: Telecom Logic Board
• unit type: Unit
• material: Plastic

seller pcbemdev:

• # reviews: 109
• city: Gulf Shores, Alabama
• rating: 99.0%

shipping pcbemdev:

• carrier: USPS
• cost: $8.46
• service: USPS Ground Advantage
• type: Calculated
• transit: 5-12 Days
• class: Standard

general pcbemdev:

• Electronic Components Semiconductors > Circuit Boards Prototyping > Printed Circuit Boards PCBs
• condition: For parts or not working

payments pcbemdev:

• credit card: Diners-club
• wallet: Google-pay
• other

offer pcbemdev:

• best offers: True
• options: Ship-to-home
• sold: 0
• started: April 16, 2026
• quantity: 1
• availability: In Stock

returns pcbemdev:

• policy: No Returns

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