Description
RDJ Controls Model 400 Resbox Guzik 303600 Extender Controller Board MR Coil
The RDJ Controls Model 400 Resbox is a specialized resistance control unit used in hard disk drive testing and certification systems. This unit includes a Guzik 303600 Extender Controller Board mounted in a red anodized carrier assembly. The front panel features a large rotary control knob and three green LED status indicators labeled MR-Coil, Coil, and MR, which are used to monitor magnetoresistive (MR) head resistance states during disk drive evaluation and certification. The black metal chassis provides a stable benchtop platform, with a right-angle mounting bracket on the base.
Specifications & What's Included
- Manufacturer: RDJ Controls
- Model: Model 400 Resbox
- Included board: Guzik 303600 Extender Controller Board
- Board marking: Guzik Extender Board, 303600 REV (revision suffix partially obscured)
- PCB origin: Made in USA (© 1984 marking visible on PCB)
- Power input: 7.5–25 VDC (rear-panel DC jack)
- Front panel controls: Large rotary knob with LOCAL/REMOTE and POWER/OFF switching
- Front panel indicators: MR-Coil (green LED), Coil (green LED), MR (green LED)
- Rear panel – Computer I/O: DB9 (RS-232 style) connector
- Rear panel – Meter: Banana jack outputs (red and black)
- Rear panel – Power: 7.5–25 VDC input jack
- Rear panel – Serial number label (number not legible in photos)
- Form factor: Benchtop/desktop with right-angle base bracket
- Chassis color: Black (base), red anodized aluminum (extender board carrier)
- Condition: New old stock — unused, out of original packaging
Applications
The RDJ Controls Model 400 Resbox is designed for use in hard disk drive test and certification workflows, specifically for evaluating magnetoresistive (MR) and thin-film read/write heads. Guzik Technical Enterprises is a well-known manufacturer of disk drive test and certification systems, and the 303600 Extender Controller Board is a component of those test platforms. The Resbox interfaces between a computer controller and the test fixture to provide controlled resistance references and monitoring for MR head characterization — a critical step in qualifying disk drives during manufacturing and repair. The DB9 computer I/O port allows integration with automated test software, while the analog meter outputs support direct bench measurement. This type of equipment was primarily used by hard drive manufacturers and disk drive service centers from the 1980s through the 2000s and continues to have value in legacy drive certification and repair environments.
This RDJ Controls Model 400 Resbox with Guzik 303600 Extender Controller Board is new old stock. The unit is unused and in new condition, though it may not be in its original box or original packaging. The chassis and all components appear clean and free of wear. The Guzik 303600 Extender Controller Board is installed in the red anodized carrier assembly. Please view our photo set and contact us if you have any questions.
Warranty Information
Additional Information
Brand: |
RDJ Controls |
Model: |
Model 400 |
MPN: |
303600 |
Secondary Model: |
303600 Extender Board |
Type: |
Resbox / Resistance Control Unit with Extender Board |
SKU: |
26954 |
Condition: |
New – Old Stock (may be out of original box) |
Seller Notes: |
Includes Guzik 303600 Extender Controller Board installed in unit |
Compatible With: |
Guzik disk certification and MR head test systems |
Included Components: |
Guzik 303600 Extender Controller Board |
Power Requirements: |
7.5–25 VDC |
Interface Type: |
DB9 Computer I/O, Meter Output |
Indicators: |
MR-Coil, Coil, MR (green LED) |
Form Factor: |
Benchtop / Desktop |
Country/Region of Manufacture: |
USA |
Application: |
MR head resistance testing, disk drive certification |
Connector Types: |
DB9 (Computer I/O), banana jacks (Meter), DC jack (7.5-25 VDC) |
Condition Notes: |
RDJ Controls Model 400 Resbox with Guzik 303600 Extender Board. New old stock — unused and in new condition; may not be in original packaging. Clean with no signs of wear or use. |
