Oh, I have a budget... And while it's not tiny, it's not as impressive as my test bench might indicate.
I was thinking of buying a nice piece of test equipment, and when I looked at the prices for current equipment and decided I could buy a lot of old equipment for the same price. It also let me buy equipment that I might only use once for a price that meant I really wasn't much out of pocket. And, I'm not afraid to fix stuff if it's broken. So I bought a crap-tonne of equipment, and I'm fixing it up, giving some away, playing with the rest.
Here's an annotated image of my bench:
- A - HP54111D 500 MHz 2 channel digital scope. Very little memory, and the colours are weird on the screen, but it's accurate and very useful for repetitive signals (it has very little sample memory). This is my go-to scope for looking at rising and falling edges because it also does a great job of measuring them. Sitting on top of this is a HP1142A Probe Control and Power module which goes with the very high frequency probes I have. It's also noisy in operation -- from airflow, not from noisy fans. I have posted images of the screen of this from time to time. The trigger inputs are on the front.
- B - Philips PM3055 60MHz scope. An analog scope I've had for ages. Power supply on this blew up once and was the subject of a post here. This is a really nice scope and is what I use most often. Most of my posted oscilloscope traces are from this.
- C - HP8590A Spectrum analyser. Got this for a really good price. It's perfectly functional except for the oscillator stability which is more annoying than anything else. I use this for making sure high frequency oscillators (or similar) aren't doing something they shouldn't. As an example, when I posted about making the highest frequency oscillator possible from standard 74HC chips, I used this to test that I wasn't just generating high frequency noise (which one design did, although it didn't show up like that on a scope)
- D - My HP3665A Dynamic Signal analyser. I have wanted one of these since I first saw one operating in the early 1980's. These are amazing beasts. The specs on this are not much different from the more modern replacements, although this is slow and has not much memory in comparison. Covering frequencies between 0.0002 Hz and 102.4 kHz it allows me to measure gain, distortion, and frequency response of audio equipment. I barely scratch the surface of what this can do, but I paid almost nothing for it. I actually have 2 of these and I bought another memory board. I have successfully upgraded the other one from 2Mb to 8Mb, and both have all of the useful software functions enabled. Bought new in the 80's, both of them would have set me back in the order of $USD70k, but I've paid less than 1% of that, and I have great fun with them.
- E - HP428B clip-on DC ammeter. FSD from 1mA to 10A, and the ability to sense the direction of the earth's magnetic field make this a useful instrument. The ability to sense the earth's magnetic field means you really need to keep the probe still, and oriented in the same direction as when you zeroed the meter. This has 7 vacuum tubes in it. At first I thought it was older than me, but it is a relatively recent model -- I was already walking and talking when i was made. These were originally manufactured and aligned with a specific probe. Unfortunately, this didn't come with a probe, so when I found a probe I had to realign it. I eventually bought two of these and passed one of them along to a colleague. These precede commercial use of Hall-effect sensors, and instead measures the difference in the current required to saturate the core of a split toroidal ferrite core.
- F - Keithley 228 Voltage/Current Source. You might think of this as a low resolution SMU. I think I posted my original setting up and calibration of this, along (maybe) when I had to do a subsequent repair. This can source or sink up to 10A at up to 10V, or up to 1A and up to 100V. It works well as a programmable load.
- G - HP3312A Function Generator. This is a cheap and cheerful signal source. It gets most use in troubleshooting audio equipment.
- H - HP5316A Universal counter. This has an ovenised reference which I have calibrated using a GPS disciplined 10MHz signal source (which is not visible in this photo). Whilst a cheap and cheerful tool, it is capable of quite a lot, including frequency differences and ratios, period measurement, and just being a counter. Most often used for measuring frequency. I could use the aforementioned 10MHz source, or my Rubidium frequency standard as an external clock source, but there's rarely the need.
- I - HP400E RMS reading voltmeter. This cost me almost nothing, it's now calibrated, and I rarely use it. But it does fill up a gap that won't fit anything else (see J and K).
- J - A set of once very expensive Anritsu test equipment that I got for a song quite some time ago. The synthesised level generator (middle unit) is a great frequency source, and quite accurate. I used (and use) this as a frequency source when I want a precises frequency and level. This has been replaced by other equipment and will form part of the hole that a new piece of equipment will fit into
- K - Another set of once very expensive Anritsu equipment. I've used it a few times for things that it wasn't designed for, but I've not played with some power line data transfer stuff I wanted to get into where this equipment would have allowed the measurement of bit error rates. It will be consigned to my rack of "unused equipment" and filled with another exciting tool!
- L - Philips PM-5192 programmable synthesiser/function generator. A more recent buy. 0.1 Hz to 20 MHz, with various modulation options. This will replace (J), but it not as simple to operate as (G).
- M - HP54501A 100MHz digitising oscilloscope. This was put here to test (that's what this stack of equipment is). It works fine and I am yet to decide what to do with it. I have to decide if I want to keep (M) or (P). Again, this doesn't have a lot of memory, but it has a really good front end and does lots of measurements. Only monochrome though :-(
- N - HP3456A Digital Voltmeter. Works fine. If you talk to some "volt-nuts" it's has the potential to be more stable than it's successor (see Q). This does Voltage and 2 & 4 wire resistance measurements, but not current. It is also a very large (long) piece of equipment and will probably end up in someone else's shed...
- O - HP54100A Digitising Oscilloscope. This originally had the world's noisiest fan, but now it's a lot more quiet. It's also a 1GHz scope and has removable pods on the 4 channels. The trigger input is on the back (which is a real pain).
- P - HP54502A 400 MHz 2 channel digitising scope. The lack of a power switch on the front panel is the most annoying feature. This is my alternative high frequency scope. It's quite nice to use and has a very crisp display.
- Q - A pair of HP 3457A Multimeters. These are a great tool and get used all the time. Yeah, I have 2 of them. I haven't calibrated them yet. One is currently in spec, but doesn't measure current (and it's not the fuse). The other works fine, but it a little out of spec, although hardly enough to worry about.
- R - HP 6827A bipolar power supply. Basically, this is either a fairly standard DC power supply, OR an AC power supply, OR a low frequency power supply. I've used this when I need voltages higher than some of my other power supplies, or coupled to a signal generator to create a low impedance (and possibly high voltage) signal source. Yes, it can drive a speaker I've not used it as a plain AC power supply, but the possibility is there.
- S - Kepko APH-1000M 0-1000V 0-20mA power supply. Before you ask, no I've never been bitten by it, and I intend to keep it that way. As it is configured, both outputs are floating. This is a vacuum tube power supply and takes about 20 seconds to warm up. My go-to power supply for high voltages, I used it last night to test some high voltage capacitors. Voltage and current are both 10 turn pots.
- T - Keithley 590 CV analyser. This is really designed for testing the capacitance of semiconductor junctions. I want to do that (just for the fun of it). I've turned it on and verified that it is functional, but sadly, I've not had time to play.
- U - A pair of Wayne Kerr 7010 High Speed Component testers. They're both a bit out of spec. Fortunately @Ian was able to get me both the user and service manuals, so I hope to get them calibrated in the future. These output most of the useful information out of a port on the back, so I also need to create an interface to bring it out to a front panel display. If you want to know the inductance of your wirewound resistor, or the Q of a capacitor (at various frequencies) then this is the tool for you (and for me).
- V - This is my home-built enclosure for an autotransformer. The size (that you can't really see) is due to two large analog voltage and current meters on the front. I use this LOTS, sometimes in conjunction with a large isolating transformer that would kill you if you dropped it on your foot (OK, maybe an exaggeration).
You can also see more equipment that is unlabelled. Almost everything is tested and working, but it is unused at present. You may be able to spot an additional HP 3457A which is a parts unit.
And do you remember I said that the stack of (J) and (K) would be being replaced... They will be replaced by this:
It's a Tektronix 577 curve tracer (the one with the storage screen). The only fault at present is a lack of a couple of screws and a noisy pot.
edit: That's the inside of my "garden shed"... or so it appears from the outside.
edit 2: So only 5 scopes. And I'll cut that down to three. But which 3? Aaaaagh!
