Posts Tagged ‘Vintage’

Tektronix 2465A Oscilloscope Evaluation

Low Voltage Power Supply Capacitor Checks After I arrived home from the Thunderbird hamfest, I put the Tektronix scope on the bench for a quick evaluation. The scope had been sold as “working, but failed cal test”.  Upon powering up, I found that the display was shrunken to the center of the screen, both vertically […]

Leave a Comment

Heathkit C3 Condenser Checker – Restoration

Ok, I’ve received my order from justradios.com.  Now it’s time to replace almost all of the capacitors and a good number of the resistors in the C3 Condenser Checker.  We’ll follow that up with a basic checkout, and finally finish up by testing the caps and resistors that we pull out. Here is what we […]

Leave a Comment

Heathkit C3 Condenser Checker – How it Works Part 3

In Part 1 of this series of posts, I introduced the Heathkit C3 Condenser Tester Wheatstone Bridge operation. In Part 2, we traced out the schematic of the Resistance and Capacitance measurements. Here in Part 3, we will delve into the Leakage Test function of the tester. The Leakage test operates by placing a selectable […]

Leave a Comment

Heathkit C3 Condenser Checker – How it Works Part 2

In my previous post, I described how the basic Wheatstone Bridge works, and how that circuit was utilized to find resistance and capacitance values in the Heathkit C3 Condenser Checker. In this post, we will look at the schematic diagram in two different forms to show some details of the circuit. The drawings in this […]

Leave a Comment

Heathkit C3 Condenser Checker – How it works

The circuit description in the C3 manual does not go into many details about how the circuit works.  Although the circuit diagram is not drawn in the familiar layout for one, it may be traced out to arrive at a reasonable resemblance to a wheatstone bridge circuit. (credit diagram below to https://goforaplusplus.wordpress.com/2011/09/08/wheatstone-bridge/)

Leave a Comment