Test Equipment Anonymous

Ah well, I won't be selling, then. That's disappointing! I have some big old diode studs here that I need to look through to see if there's anything suitable. I doubt there will be, though, this is a *very* big device.

This sounds like rather a pain to me, especially with it being a Frankenstein number. What's the big diode you are looking for? I have a few in my collection. I can't help with the inductor. I shan't go to MK. It was rather a trek, was hard to find and wasn't great last year. This year they say the...

Excitement built this morning as I cleaned up the nicely specced HP 6038A 200W 60V/10A power supply that I'd bought from a well known regular at the Rugby rally. Oh. It needs a new fan and it's producing an error state and almost no output. GPIB was working and I was able to check the numerical erro...

This is worth a look if you like mechanical and electrical bits, https://www.youtube.com/watch?v=JBRENGAtSRU inside a R&S ZDU instrument, at 26m40s there's a rotary variable delay line which uses some wonderful engineering to maintain the transmission line properties all the way to the rotary co...

I think the cancelled Newbury boot sale sent more people to the chaotic crater-filled McMichael that year and the combined experience made them less enthusiastic about rallies generally. This year I managed to fail to sell at both because of factors unrelated to the events. I live in Berkshire but I...

The chap with two 2018s on his stand had one for £20 which I bought, the other was £70 (working but needs ICs reseating to make it boot) and I'm fairly sure it went for £70. The second one I bought was on the stall to the left, which was tucked under the table and not that obvious. It was priced at ...

Today I completed the level calibration after checking the level meter (RACAL-DANA 9303) against my Boonton power meter calibrator and cross referencing the levels with a RACAL-DANA 9302 and Fluke 8920A (for the <30MHz checks). I am pleased with the results, it's now within 0.1dB everywhere, which i...

Back to the 2018, for a moment. Yesterday I pulled the version 12 firmware out and replaced it with version 23 firmware. It hasn't made any obvious difference but I've read both sets of EPROMs then looked at them in an 8085 disassembler and there are many differences in the code. I really need to ma...

It's quite tempting to populate the doubler and flip the bit in the configuration that tells it that it's a 2019 and not a 2018. The RF amplifier is capable of the full frequency range and there's an extra calibration point for setting the levelling from 520 to 1040MHz.

I bought two Marconi 2018s at the Newbury rally, both not working and a few keys missing from the keyboard - though not the same keys. One was £45 sold as "stopped working during storage" and the other was £20 and sold as incomplete. The incomplete 2018 was missing its Frequency Standard b...

New arrival, Panasonic VP-8191A. Works, looks to be in good physical shape and will do a signal to spec. Thought it would do stereo modulation, but no. That was just me in delirious acquisitions mode. Now researching stereo MPX modulation generators. NJM 2035 plus quite few extra components will do...

I've opened an HP OCXO to replace a thermal fuse. You can get to it without unfurling the bits that shouldn't be disturbed but the outer metal skin needs to be removed. It's in a socket but that might just be to simplify assembly as a soldering iron would definitely open it. It's a very small wire-e...

I volunteered to do some work for a community radio station that site shares at a fairly well populated Arqiva site in Surrey and one of the things I'd need to do was take some measurements that would require a spectrum analyser with a tracking generator. I have two Anritsu MS2601A analysers, they'r...

Well that's rather sad.

KO4BB was working recently and I've downloaded the firmware and operating manual now.

Jackson's of Jackson's Corner in Reading had the tube system until it closed in 2013. There's a picture of the tube office here https://whatsonreading.com/venues/readi ... omas-macey

I'm surprised they didn't use a toroidal mains transformer. It's difficult to fit an effective E/S screen to a toroid but fairly easy on an EI transformer. Worse, toroids have high C PS compared to an EI transformer of the same VA rating because the area between primary and secondary is (unavoidabl...

There's also the militarisation of space to consider. Russia has used a presumed kinetic weapon to shatter a satellite and more recently has been making threats to the ICEYE RADAR imaging satellite by moving four COSMOS satellites around close to it. USA with Boeing X-37B and likely other systems th...

At the Dunstable Downs boot sale I picked up this delightful signal generator for £20 (ignore the sticker, I waited until it had been ignored for a few hours and the price dropped) https://live.staticflickr.com/65535/55309471518_ae425cc2c0_c.jpg It's a nicely made signal generator with incredible in...

1s/div of course, I get that wrong a lot because some of my instruments show the per division setting in that central position. I also tuned my MDA's OCXO to Droitwich and have wondered if I really needed the GPSDO afterwards. I decided that I did but I'm not sure that GNSS availability is guarantee...

Decided I ought to dig out the relevant equipment, and do the measurement one last time. What is the equipment, what is the measurement, and why one last time? :) IMG_0295a.JPG You've left the name of the instrument in the picture and I had no idea it was produced with the Agilent name on it, that ...

That HP is very tidy and elegant. One of the rare opportunities to feel annoyed with British mains sockets, as you'd be lucky to fit just one on that front panel and even then you'd have to move the knob off-centre and use all sorts of bevel gears to get the driveshaft back to the middle of the vari...

I've a memory of most of the Jackson Bros stock being destroyed in the fire at Electrovalue after the move from a shop in Englefield Green to larger premises in Egham. After that Mainline bought what was left of Jackson Bros, tooling and some stock that had escaped destruction or something. I've for...

I was digging through the components in tubes to find these and then I realised I was mixing up two different repairs that I did at the same time. The level shifter CMOS is actually in my RACAL 1792, the CMOS that failed in the 2019 is a CD4056BE which isn't an endangered species just yet.

The "Curcuit" for this RF signal generator is suspect, the JFET Q1 doesn't appear to have anything but a capacitor connected to its drain.