I manage to secure one vintage tube tester, a Hickok 539B. This is an ultimate tester, Lab grade, and one of the most wanted tester on eBay. Don’t ask how much did I pay for this. This is also a very heavy tester. I believe it’s over 10 Kgs. So please also don’t ask the shipping cost to deliver this item from other continent.

It has dedicated meter to monitor the AC line voltage. The reason is, during the testing process, the line voltage may have some sag which will affect the measurement result. So with this dedicated meter, we can confirm whether we have a drop on the AC line voltage or not.

A dedicated bias meter. Also very useful to measure regulator tube, like 0A to 0D tubes.

A huge main meter to show the micromhos value. We have six different signal here.

The top view from the tester. Many socket to cover almost most of your needs! An optional even more sockets is available also, most likely on eBay.

The outer appearance does need a big rework. I’m thinking a nice brown wooden case. Also this unit must be recalibrated prior serious usage.