The Hickok 539B is considered one of the finest mutual conductance tube testers ever made. I restored and calibrated this tester for accuracy and long-term reliability. A true workhorse for any serious tube collector or technician, and it’s an excellent choice for tube matching – providing both Gm and plate current measurements. It also comes with a one-year warranty for your peace of mind. See warranty details here.
Restoration:
- New meter – replaced for long-term reliability
- Solid-state rectifiers – replaced tube rectifiers for improved stability and reduced transformer loading
- New Roll Chart – 1970 edition for expanded tube coverage
- Capacitors replaced – capacitors prone to failure replaced
- Resistors replaced – resistors affecting calibration and accuracy replaced
- New 5Y3 Socket – I replaced the broken 5Y3 tube socket
- New grounded power cord – modern safety upgrade
- Grid and Plate lead – replaced damaged lead wire
- Socket savers – added for protection of Octal and 9-pin sockets
- Bias circuit protection – Bias fuse lamp added to guard against Bias circuit damage
- Plate current conversion – you can now use an external voltmeter (no need to rely on a milliamp meter)
- Transformer balanced – optimized for consistent operation and accurate test results
- Calibration – calibrated to factory specifications and verified across multiple tube types
- Corrected prior repair issue – I fixed an incorrectly installed component and restored proper operation
Key Features:
- Tests transconductance (Gm), plate current, shorts, and leakage with laboratory accuracy
- Excellent choice to match tubes
- Professionally restored and calibrated for dependable operation
- Electronics are in excellent condition – fully verified and reliable
- One-year warranty included
Condition:
Electrically, this fully serviced Hickok 539B deck is in excellent condition. I fully restored and calibrated it. The case shows significant cosmetic wear from age and prior use, with evidence of possible water exposure. I re-glued and reinforced the case. It is now sturdy and fully functional, but is still cosmetically rough. There doesn’t appear to be any deck and electronics damage. The glass on the Bias meter is cracked on the left side, but the operation is not affected.
This restored and calibrated Hickok 539B is clean, electrically excellent, and ready for service. The Hickok 539B tube tester is priced fairly to reflect the rough case. This is a great opportunity to own a top-tier Hickok tester at a lower cost than pristine examples.
The manual is available to download here
This Hickok 539B tube tester is $875 plus shipping to the lower 48 states only because of the weight.
Contact Me if you are interested in this tube tester.
