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I'm a bit of an instrumentation nerd these days. I rarely need to do RF measurements at near-DC frequencies (that is < 2 GHz) but I can't afford a VNA that will cover my ranges of interest.? I have a PocketVNA, NanoVNA H4 and LiteVNA 64 that sort-of work OK above 3 GHz, and some can go to 5.7 GHz with limited accuracy, but my budget won't stretch to the sort of kit I need to cover 5.7, 10, 24, 47, 76, 122, 134, 241/248 GHz and higher.???

I have a counter that will go to 20 GHz, HP and Agilent spec-ans that cover up to 50 GHz, signal generators to 27 GHz, calibrated diode noise sources to 6 and 18 GHz, plus gas discharge sources to 40 GHz, but there are serious gaps that I need to address without spending all my pocket-money allowance. All of the kit is very much second-hand and low cost.

I have some slotted lines for several frequency ranges to 40 GHz, and I'm building adaptors to cover other ranges using the standard Marconi Instruments slotted line carriage. I'm working on some machining slotted line rigs for some higher frequencies so I can make precision measurements at 24 and 47 GHz.??

I can do length/diameter measurements to within a micrometre, so wherever possible, I'm using tools that work from length or angle measurements (slotted lines for coax/waveguide, sliding shorts, sliding loads, cavity wavemeters, attenuators) without relying on any transfer standards or calibrations other than the attenuators. I can do pretty much whatever a VNA can do, but it takes at least 20 times as long.

I have some Rubidium sources plus a few very well-aged Morion quartz DOCXO devices in anti-vibration and insulated mounts, which are trimmed against (but not locked to) GPSDO sources, which are less than good over periods of less than a minute. I use a really neat BG7TBL FA-2 8 GHz reciprocal counter that gets to 11 digits quite rapidly.

My HP ESG series signal generators are noisy, but locked to GPS, but for higher frequencies I use multipliers and comb generators driven from 100 MHz OCXOs phase-locked to the Morion references. I have some Klystrons, various high power magnetrons, Gunn sources and even a couple of backward-wave oscillators, plus a range of YIG oscillators and YIG filters. For lower frequencies I have a super BG7TBL signal generator that was excellent value.

I don't have any precision voltage standards other than a Fluke 8845A 6.5 digit DVM which is still in calibration.

I have a Hutales LCR meter, but I rarely need to measure discrete capacitances or lumped inductors. Mostly I'm measuring microstrip, grounded coplanar waveguide and coaxial or simple cavities.

I have an HP 8970B noise-figure meter to work with the various noise sources.? One source is still in calibration and I use it to calibrate the others, but I'm working on some proper hot/cold sources using cold sky and a heated absorber panel as references, to avoid having to rely on transfer standards.

For RF power measurement, I rely on a range of thermal and diode heads, mostly HP/Agilent/Marconi, and some good quality power attenuators (eg Wiltron, Narda, H&S, HP) including one that's good for 100 W for DC to 18 GHz, and vane attenuators for various different waveguide sizes, plus some stepped attenuators.? I have some Narda/HP directional couplers, and some home-made directional couplers with calculated coupling and directivity based on precise diametric and linear measurements then calibrated against known good attenuators and power meters.??

I'm working on a proper DC-replacement calometric thermal flow power meter using only DC voltage and current measurements, so that I can use it to calibrate my other instruments.

For other RF measurements, I'm building some Fabry-Perot open resonators to make dielectric permittivity and loss tangent measurements, and a range of split-post dielectric resonators for the same function.? Those are all low-cost and simple enough to make in a home machine shop, and are mostly self-calibrating.? I'm also making some coaxial dielectric test jigs, again using precise linear and diametral measurements based on physical length standards accurate to better than 100 nanometres and a granite surface plate and Mahr gauges accurate to better than a micrometre.

I have made some precision capacitors in the past, with guard rings to eliminate fringeing, but they aren't much use above a few MHz.

I have some commercial EMF measuring heads (EMCO) and I've made a TEM cell to calibrate them, along with some home-made sensors.? Over the winter I'll be making a much larger 50 ohm open TEM cell with an internal septum and a volume of 2 x 1 x 0.7 metres.? Again, this is self-calibrating using precise dimensions, leaving only RF power measurement to be defined. The plan for that is to review a range of the tinfoil-hat-wearer EMF measurement devices in known fields so I can make a video debunking (or otherwise!) their performance.

For magnetic fields, I only have some Helmholtz coil pairs to generate calculated fields, and some Hall sensors.

For vacuum measurements I have some Pirani gauges to measure from atmospheric down to 1e-7 atmospheres and Penning gauges good to 5e-11 atmospheres (using a radioactive beta source, big magnet, 2.3 kV accelerating voltage and using the resulting spiral electron flow as an analogue of pressure).

I don't have anything to measure optical or RF power above about 100 GHz (yet).

I have a dual-tube Geiger counter for beta, X-ray and gamma.

I don't have anything to measure voltages greater than 3kV although I have a variable power supply running up to 50kV which has a meter.

I have a truly terrible digital scope with recording facility and a load of functions including Fourier analysis, but it only goes up to about 200 MHz, so I only use it very rarely.?

I plan to make a quadrupole mass spectrometer for gas analysis measurements and lots of testgear related to making thermionic vacuum devices such as magnetrons and gyrotrons.

My entire lab philosophy is based on using cheap, solid, ancient technology and calibrating where possible by transfer from calibrated length/weight standards, plus a calibrated DVM and thermometers calibrated with known melting/boiling points and my frequency standards ultimately referred to GPS time.? "Budget" is relative of course, I choose to waste my pennies on testgear and machines instead of radios, fast cars and high living!