Re: Favourite Test Equipment

On 12/04/2024 5:42 am, Phil Hobbs wrote:

On 2024-04-11 13:11, john larkin wrote:

On Thu, 11 Apr 2024 09:55:18 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2024-04-10 16:30, Trevor Wilson wrote:

On 11/04/2024 3:42 am, Cursitor Doom wrote:

On Wed, 10 Apr 2024 11:40:02 +1000, Trevor Wilson <trevor@rageaudio.com.au> wrote:

On 1/04/2024 4:41 am, Cursitor Doom wrote:

Hi all,
>
I'm starting to get a bit fed up with having my test equipment blow up
just when it's needed. This is the drawback with vintage gear; if it's not used frequently then it can go *bang* the next time you switch it on. It makes for good practice in repairing stuff, but wastes a lot of time which could be better spent doing other things.
I think it's time I modernised my test gear. I was just wondering if
anyone has any recommendations they can share. Is there a particular
piece of test equipment you couldn't live without? Something you're
particularly impressed with? I'd be interested to know so I can
perhaps acquire said item and thereby reduce the number of explosion I experience.

>
**In my 55 years of servicing, I've only blown up one thing: A Micronta DMM, which I connected to a laser power supply. I should not have done it. Clear operator failure. Everything else works just fine. Even my
first multimeter. A Sanwa U-50D my dad gave me on my 14th birthday.
Still works fine. My first DMM. A cheap 'n cheerful SOAR. Works just
fine. My first Fluke meter. A 40 year old Fluke 85. Works fine.  I've had
to clean the switch a few times. Otherwise, no problems. Ditto my other 15 or so meters. Same deal with my 'scopes.
>
I don't know what your problem is. Test equipment, when treated properly lasts a long time.

>
To be fair, these "explosions" are typically capacitors: old, dried
-out electrolytics in test gear that hasn't been used in a long time
go bang when the power's switched on - as do old X2 safety caps. Those
are the chief culprits IME.

>
**Oh, I see. You ignore regular maintenance. That makes sense. I hope no-one buys a car from you.

>
Whereas all you Ozites are 100% rational reasonable polite beings who
are always on top of everything, including predicting the exact date
when an old cap will give up the ghost.

Old electrolytic capacitors tend to give up the ghost when they have been left unpolarised for years, and are then subject to their rated voltage without having been re-formed first.
Predicting that kind of failure isn't difficult.

Silly me for forgetting. ;)

You don't have much to do with clueless newbies.

You don't routinely replace caps in all your test gear? I'm shocked,
shocked.

You don't replace them, you re-form them -  day or so subject to rated voltage applied through a nice big resistor (100k comes to mind).

Sad but true. ;)
>

(My nice little HP6212A power supply must be 50 years old. It's never
been opened and works great.)

 I have a number of the 611x supplies, including the 3 kV one.  Only one has ever actually failed--it was my previous 3 kV, whose transformer started arcing internally, so I tossed it.
 In good equipment (HP & Tek, 1985 or so on), age-related failures are much more common on the outside of the front panel than on the inside. (A problem not unrelated to PEBCAK.) ;)

Problem Exists Between Chair and Keyboard.
--
Bill Sloman, Sydney