Custom Upgrade Examples

The following are two examples of custom modifications; one complex and one simple.

Hickok 750 Custom

The Electronics were built into the back compartment. Upgrade included an AC line set meter to accurately set, monitor and maintain the correct AC line voltage at all times. It included a digital bias meter to set and monitor the tube's DC Bias point during the test. An amplifier was installed for the noise circuit so an external one is not required. Pin jacks were provided to measure the voltages on the tube under test (TUT). This is helpful when a Bogey tube is available to more accurately check the testers calibration, and operating voltages.

The tester has my solid state SS-83 and SS-5Y3 power supply installed which is designed to meet the correct operating values for Hickok tube testers. Correct calibration for all tubes is guaranteed! The tester has a high current 6.3 volt (5 amp) filament transformer add to support high current power tubes reducing the load on the internal transformer and improving the measurement accuracy. This tester also has a new Mutual Conductance meter installed in it.

Hickok 533 Custom

Our second example is of a simple modification:

In this case a customer requested the ability to use an external meter (DMM) to monitor key parameters.

This is a Hickok 533 tester with the addition of pin jacks so the customer could connect his DMM to measure the AC line set voltage accurately and at test. In addition he can monitor the actual DC bias voltage or set the tester for a more accurate bias voltage. There is also a plate current terminal to allow the customer to measure the plate current. This setup allows for tube matching!

The customer choose to add the modifications on the top panel directly. A panel was built, the parts were mounted to it, and each item was labeled. A warning label was added for safety reasons. This upgrade was added to the top left hand corner of the tester at the customer's request.