Test Equipment Anonymous (TEA) group therapy thread

[Robert763]

Speaking of Fluke, I seem to have a problem with their fuses, i.e. they no longer supply them. 
Anyone got a suggestion of a replacement for a FP375 250mA 6.35mm x 32mm (¼" x 1¼") 10kA fuse? It's used in my Wavetek HD160B DMM.
Preferably from a reputable source, such as Mouser, RS, Farnell.

David

How about an Eaton / Busmann MDA series?
https://uk.rs-online.com/web/p/cartridge-fuses/8527027?
It's ceramic with a 10,000A rupture rating. That is at 125V AC the 250V rating is only 35A. The big difference may be partly due to different test standards.
Data sheet https://docs.rs-online.com/1eaa/0900766b813d739b.pdf
Certainly better than a unknown glass fuse....

[factory]

Thanks for finding that one, might need something faster, the one fitted was a SIBA FF250mA (very fast acting), checking again on RS there is Mersen FF at 250mA in Ceramic, that is the only other one they sell in ceramic in the same physical size at 250mA.
https://uk.rs-online.com/web/p/cartridge-fuses/1886710

Datasheet is Ferraz with different part numbers, they got rebrand as Mersen.
https://docs.rs-online.com/10e3/0900766b80144b4e.pdf

Ceramic or no fuse fitted, is better than glass in this application.

Edit: I don't like RS's alternate suggestion (as it's out of stock), a 315mA fuse, nope just nope.

David

[electronomicon]

Ceramic or no fuse fitted, is better than glass in this application.

Why is that?

[wkb]

Sounds like this is about a HRC fuse (high rupture current). Glass fuses tend to explode, produce plasma arcs and other unpleasantness.

i am no expert on this subject but there is a good reason that e.g, DMM certified for use on high energy circuits use e.g. the expensive Bussman HRC fuses.

[EggertEnjoyer123]

After messing around more with the Agilent, it seems like there is an issue with the motherboard.
I powered everything off of a lot of lab bench power supplies. After powering, nothing appears on the screen. All four LEDs on the CPU board are lit. The 5V rail seems to be drawing 5.6 amps, while the 3.3V rail is only drawing 0.5 amps. The manual claims that this might be due to a bad bootrom, or due to an issue with the reference assembly.

Here's what the manual says:

Code: [Select]

If the screen remains blank (dark) and the green LEDs never blink, the
instrument was not able to boot from bootrom. The bootrom on the CPU
assembly could be bad, or the instrument clock signals could be
missing. The bootrom is not a replaceable part.
If the 30 MHz sample clock from the A8 Analog IF assembly to the A7
Digital IF assembly is not present, the display signal processor chip on
the digital IF assembly will not reset, causing the PCI bus to hang up
and the instrument will not boot.
To check the 30 MHz sample clock:
• Put the A7 Digital IF assembly on an extender board (E4406-60021).
• Check A7J4 for a 30 MHz signal using an oscilloscope, as shown in
Figure 6-1 on page 142.
• If the signal is not present, the cause could be the A8 Analog IF
assembly, or the A11 Reference assembly. Go to "A11 Reference
Assembly Description" on page 118 to check the reference assembly
Also, judging by the number of connections going to the processor board for VDL (3.3V) and VCC (5V), it appears that the 3.3V rail is relatively low current, since 3 or 4 times as many pins are used for VCC.

[Neomys Sapiens]

As the rebuild of the 'Mini-Tracer' (Spacey Signal Tracer) is certainly not acieved soon, I have aquired a P.O. Test amplifier (type 109B) from the UK. I hope very much that this doesn't turn into a project itself.
This would be tricky, as I don't have documentation for it. Input looks like 'Belling-Lee', Output might be 1/4" tip/ring.

Also, first specimen of 13-30 adaptors was delivered to me yesterday. Those are really big ugly beasts.

[Robert763]

The output on the GPO amplifier is a GPO special 4 pole that was used on early telephone "extensions" where you had one phone and two or more sockets in different rooms. The connector looks similar to the socket for, and will accept, a "NATO" military aircraft headset plug but it will not work.  Replace or fit a 1/4" 3.5mm jack in parallel.
Input is a Belling-Lee coaxial as used on UK televisions.
If I recall correctly the electronics were potted in wax.

Robert. 

[TERRA Operative]

Sexy AF though...
(Attachment Link)

Looks like a Fluke 33(something)? I have to fix my two one day...

[edit] just saw it's a 332A. nice.

[factory]

Sounds like this is about a HRC fuse (high rupture current). Glass fuses tend to explode, produce plasma arcs and other unpleasantness.

i am no expert on this subject but there is a good reason that e.g, DMM certified for use on high energy circuits use e.g. the expensive Bussman HRC fuses.

There is 3-phase in the workshop here, this DMM is the one I use for measuring AC mains, it needs the proper rated fuses, in case I do something stupid with the leads or function incorrectly set. It does have lead detection for the 10A jack, but not the 40mA jack, the fuse was EOL'd with low voltage.

David

[EggertEnjoyer123]

I think I found the issue with the clock.

U45 seems to be dead. The input looks correct, but the outputs of the chip are stuck at zero volts, which I'm pretty sure is not even a valid NECL level.

The chip is the MC10EL16.

[factory]

A bit of luck today, I got told to move some of the TE from the living room last night, looking through one of the boxes of parts I acquired a few months back and found an edge connector for the extender board I had made.





The pictures should give away what it's for, I found the earlier extender board wasn't held in position & could touch the chassis with certain boards, the design is based on a picture from the web, the two holes were part of the divider board, I left them in place to aid removal from the oscillator board position. Guess I'll find out how long it'll last with the contacts in these counters.



David

[themadhippy]

As the rebuild of the 'Mini-Tracer' (Spacey Signal Tracer) is certainly not acieved soon, I have aquired a P.O. Test amplifier (type 109B) from the UK. I hope very much that this doesn't turn into a project itself.
This would be tricky, as I don't have documentation for it. Input looks like 'Belling-Lee', Output might be 1/4" tip/ring.

Also, first specimen of 13-30 adaptors was delivered to me yesterday. Those are really big ugly beasts.

Hippy dives deep into his junk precious treasures box


Drivers missing ,but theres also a  probe, these are from the later BT version of the test amp.I might be convinced to part with my precious  if your in no hurry.

[Neomys Sapiens]

Now this is a very helpful proposal. I have to admit, if I hadn't read the specific warning from Robert763 about this plug, on first sight it really looks like the one for helicopter headsets.

[Robert763]

The GPO and NATO plugs are very similar, see photo. The Nato has narrower insulation and consistent spacing. The GPO has differant and inconsitent contact widths.

[AVGresponding]

Wider and deeper tip detent as well, on the NATO one.

[Martin.M]

DSA 602 Digitizing Signal Analyzer.
heavy duty. The self test is extremly long working.

[wkb]

Oh yes.. we had one of those at Philips Data Systems, when I was a hardware designer ther in the late 80's / early 90's.  Fascinating piece of kit. Weighs a ton.

[Vince]

There is a guy here in France currently selling two of these in Metz, not far from the German border then... is that one of them ?

I would love to not live 1,000kms from Metz so I could pick one up, well depending on price f course....
So instead I thought of maybe asking him what plugins he had and if he would consider selling them separately (since it uses the same ones as my 11000 scope)... but I thought it would be taking the piss and I didn't want to get insulted. So I refrained...

[PA0PBZ]

I have a DSA601 for sale, with a 11A34 and a 11A32 plugin. Any offer welcome, pickup only...
Working fine as far as I can test.

[Martin.M]

the touch screen is amazing good working.
But don`t forget to switch OFF this after setting, any fly can do a complete programming of the instrument in the lights ray gate at front of the screen 

[Vince]

I have a DSA601 for sale, with a 11A34 and a 11A32 plugin. Any offer welcome, pickup only...
Working fine as far as I can test.

Bummer, the Netherlands is even farther than Metz ! 

Thanks for the offer though !

[TERRA Operative]

I bought myself a Christmas present with the blessing of my wife (OMG!)

A Siglent SDS2014X HD scope for a really good price (I think...?) Retail in Japan is 609,840yen, but on sale at 484,330yen by one seller. However while visiting family in Australia, I found a local seller with a sale at AUS$3973.35 (387,331yen)
So by carrying it back with me to Japan on the plane I save 222,509yen from retail price, like $2000 saving!

It will obviously be hacked up to 500MHz with all the options enabled ASAP.

[Messtechniker]

What about any taxes?

[TERRA Operative]

Taxes included in the prices.

No import tax on carrying it through customs.

[m k]

I have a DSA601 for sale, with a 11A34 and a 11A32 plugin. Any offer welcome, pickup only...
Working fine as far as I can test.

Bummer, the Netherlands is even farther than Metz ! 

Thanks for the offer though !

Become a football fan and hop in the bus when local team is playing against the right target.