A good test bench is a key part of my ham shack. In fact I guess it’s the key part as I derive the greatest enjoyment from the electronics end of things as opposed to the radio operating. Operating is great and is the culmination and verification of good electronics work but the greatest reward for me is understanding the theory and the associated math behind. Therein lies the true beauty. I’ve had a life-long passion for electronics and that is what I studied in my post-secondary education. As a branch of applied physics electronics has always spoken to my inner scientist.
The construction, modification, restoration and tuning of radios, antennas and feed lines is my favorite part of the ham radio hobby. I derive great pleasure in all of these activities and thus I need a good test bench that is up to the task.
In the summer of 2022 I stared at an empty room, the blank slate of what would be my next ham shack. I first needed proper benches with AC power distribution and some task lighting. And a good bench stool!
Having acquired all of the above I then needed test equipment. As I graduated from Electronics Engineering Technology in 1981 there is a certain vintage of equipment that greatly appeals to me from both engineering and aesthetic standpoints. The equipment needed to be of an excellent quality and in fully functional and – ideally – calibrated condition.
I found a good source for a lot of what I was looking for and I set about making my shopping list, acquiring equipment and laying my bench out. I already had a Digital Multi-meter that was suitable and I had lots of 12VDC power supplies but what I didn’t have was an oscilloscope, a frequency counter, an RF signal generator, an AF signal generator and a variable power supply.
I stipulated that I would only be satisfied with high-quality equipment of a certain vintage and from certain manufacturers. Tektronix and Hewlett-Packard made the best test equipment there was and this is what I wanted. Those companies made more than just the best, they also made aesthetically beautiful gear that is a joy to use.
Oscilloscope
The oscilloscope requirements: 100 MHz bandwidth, dual trace and with on-screen voltage, time and frequency measurements. And it had to be Tektronix. What I got was a Tektronix 2246 which met all of the above but with four vertical channels, not two. And fully tested and calibrated.
RF Signal Generator
Next up was a proper RF signal generator. Minimum requirements were: synthesized with a resolution of 10Hz or better, fine output level control and AM/FM modulation. And it had to be HP. I ended up with an HP 8657A. fully tested and calibrated.
Frequency Counter
A good frequency counter was also needed. Requirements were good up to at least 500 MHz and it had to say HP on the front. I ended up with a lab-quality HP 5328A with a number of good options including the DMM and the third channel with a 50 ohm input impedance for RF work. And fully tested and calibrated. Nice!
Test Oscillator
A goof AF generator was needed with the requirements of very low distortion, a 600 ohm output impedance and made by Hewlett Packard. And of course fully tested and calibrated. A suitable HP 204C was located which suited me fine as that is the very unit I used in the electronics labs when I attended the Northern Alberta Institute of Technology from 1979 to 1981.
Variable DC Power Supply
Next up was a variable DC bench power supply. I wanted something that went to at least 48 V. It had to be HP, tested and calibrated. I settled on a nice HP 6220B. It’s only got one output but it will operate as a voltage source or current source and it has a nice large analog meter movement, which I prefer for aesthetic reasons. And it has ten-turn controls. It’s a lab-quality instrument.
Multi-meters
Meters. while I already had a nice Digital Multi-meter on hand, a Tektronix DMM157, I also wanted an analog instrument suitable for working on the vintage vacuum tube radios I use. It’s easier to peak analog adjustments using an analog meter movement. A Simpson 260 fit the bill nicely and I located one locally. It needs a calibration but is otherwise good.
RF Watt meters
No radio test bench would be complete without a directional RF watt meter or two. I have two Birds, one 4304A for VHF and UHF and a 43 for HF work.
Variac
A Variac is needed to work on old equipment that may have not been powered on for years or even decades. And also for working on older equipment that was designed to operate on the lower line voltages used in the past like 110 V or 115 V as compared to what we have in our homes today.
FM Communications Analyzer
Last but not least I needed a good communications analyzer for working on FM VHF and UHF radios. A CT Systems 3000B crossed my path and landed on my bench. It seems to be in good working condition but I imagine it needs a proper calibration.
Those are the main items on the test bench. There are of course the usual other items you’d find on a test bench like a Weller soldering station, RF dummy loads, 12V DC power supplies, assorted probes and cables and so on.