Test Equipment Anonymous (TEA) group therapy thread

[Cyclotron]

Here's a direct comparison using the VFD LED replacement on my 53132A, comparing the LED against a brand new VFD. It doesn't have white, but it is the newer cyan colour instead of the intense blue of the first revision.

I still prefer the colour of the original one.
At least it's different enough for me to avoid buying any units that have this replacement, not that I actually want any counters from this range.

David

I have some of the displays with various colors on a couple of my instruments.  I do like the original VFDs. I think the look of a new VFD is awesome, but a well-sorted LED is awesome too.
I think I'd love a white LED Option, and then the lens would color it as the user wants.

But the end result is that those folks over at https://hubequip.net/ are heroes as far as I'm concerned. I know they are addressing a market, but they are passionate about this particular profession/hobby and are bringing us an option that simply isn't there much of anywhere else. What's more, they have to sink a good bit of money into creating the units and making them available.

I'm sorry, I shouldn't preach, but I'm super stoked/happy that a new display is available for so many of my favorite instruments. If someone comes along with VFDs that would be awesome too.
Now that I think of it, Hubequip might want to consider doing "group buys" for various colors because that's the only way you'll ever land everyone's preference. If you get "X" number of people to sign up the price would be "Y".  I don't know, they know their stuff so I'll stop trying to drive from the back seat..

[m k]

Here's a direct comparison using the VFD LED replacement on my 53132A, comparing the LED against a brand new VFD. It doesn't have white, but it is the newer cyan colour instead of the intense blue of the first revision.

LED style is not calm.
(my browser background is light gray)

[AVGresponding]

Solid state logic > hollow state logic

Hollow state displays > solid state displays

Accept no substitute

[zepto]

I really dislike VFDs. They somehow managed to be custom to each device without adding much to the interface. Mostly they just add an expiration date to the device. Even during the limited support lifetime TE manufacturers can gouge you on replacement. Win win for them.

At least LCDs usually add functionality to the interface.

I liked the LED displays on Fluke 8505A, Advantest R6871E, Yokogawa 7562, and old Keithleys. Legible and long-lasting.

[Cyclotron]

I really dislike VFDs. They somehow managed to be custom to each device without adding much to the interface. Mostly they just add an expiration date to the device. Even during the limited support lifetime TE manufacturers can gouge you on replacement. Win win for them.

At least LCDs usually add functionality to the interface.

I liked the LED displays on Fluke 8505A, Advantest R6871E, Yokogawa 7562, and old Keithleys. Legible and long-lasting.

I can see your points. I think VFDs look nice, and I really like dot matrix VFDs.  I think its a sign of the times when most of the stuff we tend to play with in TEAs was built.
Modern stuff has LCD/OLED and so on.  Those will be a really PIA to replace if they are anywhere near custom. 

Nixie tubes for the win.

[AVGresponding]

LCDs don't last forever either; they can get chemical rot in the glue, delaminate, UV damage, heat damage, leak across segments, and of course they are glass, so they can be shattered. They also require backlighting to be visible in many situations, and have a very slow refresh rate (comparatively), especially in colder conditions.

[m k]

My world has very slow LCD if under freezer temps.
But that's a minor thing, if you're steering a car style stone sleigh.

Maybe the earlier LED thing is a camera effect.
My experience is that generally LEDs are calm, if not too bright.

7-segments are also reasonably easy to replace, even if correct type is missing, excluding very special stuff, like pulsed ones.

[Squarewave]

So at work, we had a Hioki 8835 which was thrown out into the WEEE waste! Fully working, nothing wrong with it! So I've retrieved it. Fortunately the case and accessories was still full and to one side. Someone thought, as no one uses it, just dispose of it?!

[Gertjan]

Of course, my HP 8640B was missing some contacts / wipers on it's rotary switches.

This post is mostly a heads-up for an alternative source for wipers for HP rotary switches.

I found K6JCA's excellent blog post Repair Log: HP 8640B Rotary Switches and Gears.
What was new (to me), that he found a source for the original HP contacts / wipers for these rotary switches! He found that the same wipers are used in HP's slide switches:


pulse_gen_1-1000pix.jpg (photo K6JCA)

I posted about this on the Dutch Circuits Online forum.
Much to my surprise, next day I found an envelope in the post, containing a few of these slide switches!
Member PA1WBU (wkb here on EEBblog) read my post, and chucked a few switches in an envelope:


IMG_7038__HP_8640B_reserve_wipers_van_schuif_schakelaar-2000pix.jpg

The wiper in front fell out of my generator while handling it. The one behind I removed from the slide switches.

So, one day I was doubting if I would ever find these wipers. Reports from the interwebs of people improvising these wipers from relay contacts etc. were not very hopeful. And a few days later I had these wipers, delivered to my home, free of charge! One starts to believe in miracles.


The rotary switch on the A1 RF vernier lost all three wipers:


IMG_7041__HP_8640B__A1A1_RF_vernier_-_old_repair_bodge_wires-2000pix.jpg

The previous repairman had bodged jumper wires over the missing  contacts. (The brown wires in the photo). That is why the output attenuator was still more or less working. Albeit without +20dBm output, and correct meter indications.

Three new wipers glued to the A1A1 S1 switch rotor:


IMG_7049__HP_8640B__A1_switch_rotor_with_new_wipers-2000pix.jpg

I glued the wipers with a tiny bit of epoxy. (Bison Kombi Snel/Rapide). These rotors have 2 sets of "nipples", to mount the wipers and hot-stake them. The original set was broken off (on the far side in the photo). But the spare set was pristine, so I used those.

The A1A1 RF vernier assembly repaired:

IMG_7051__HP_8640B__A1A1_RF_vernier_-_repaired-2000pix.jpg

With the output attenuator fully working and in spec again, the last thing to repair is that pesky A9 assembly. Gears with cracks, but not broken, and switch rotors without wipers again.

regards, Gertjan.