Test Equipment Anonymous (TEA) group therapy thread

[Brumby]

 

You guys are dangerous.  I've just spent the last hour looking at NanoVNAs.

No ... I don't need one.
No ... I don't need one.
No ... I don't need one.
No ... I don't need one.

* turns to the 3D printer still patiently waiting *



Never enough hours....

[tautech]

I have seen Bananas straighter than this POS molding. Time for a beer to decide what to do about it and even if it will help keep the zebras in the right spot.

$60+frt for the frame and $230 for the LCD if it needs it 

Thin strip of high density foam ?

[beanflying]

I have seen Bananas straighter than this POS molding. Time for a beer to decide what to do about it and even if it will help keep the zebras in the right spot.

$60+frt for the frame and $230 for the LCD if it needs it 

Thin strip of high density foam ?

Full strip clean of zebras, contacts etc and re assembly yielded the same LCD fault. As it is only a single path and the lower bars on the upper digits it is still translatable.

The Zebras are held in position by the four white clips to the pcb and any cantilevered force from the three  screws holding the board in the case. Evrything at the top of the PCB is flapping in the breeze between the outer case.

It is still possible that a PCB or the outer frame warp is stopping the zebras from contacting bit I am leaning toward the LCD having a dud track.

I think it suffers from being the bastard love child of Fluke and Martel who forgot to consider some basic mechanical design considerations.

[tautech]

Hmmm, a sleep on it usually helps. 

[bd139]

Good advice.

Certainly a pain. All Flukes seem to suffer LCD problems 

I noticed that when Heathkit ripped off the Fluke 8021 they used a standard LCD module with standard pin layout. The side effect of this is you can still get exactly the same module. While I like some of the custom LCDs we’re an in age now where everything should have standard matrix LCD modules and all the fun stuff done in software.

[URI]

Hmmm, a sleep on it usually helps. 

I can confirm that.

Today I feel it's better to skip the 5373A and to go for a 53310A with option 031.   

Thanks all for helping me with their thoughts on it!   

[beanflying]

Sleep might help the thinking but it won't help the nearly 70mm of floating PCB/LCD above the screws. There is room where the Fluke and Martel logos sit to have added two more screws so it is either an ego Branding or dumb dumb engineering fail. Adding a wedge to the slots in the case insert might help keep the board in place.

As it is usable I won't be rushing into a new LCD. But interesting they are available off the shelf in Oz from their service agent shows them to be a failure point.

[tggzzz]

I unpacked the 184, which was boxed up quite nicely, and took a few photos. Thread to follow. It was definitely stored in less than ideal conditions - incredibly crufty slide switch contacts, for example - but is not in bad shape internally. 

Building a compact, stable, clean 500MHz oscillator in 1965 was a challenge, so it is full of interesting looking circuits.  I am going to enjoy working on this one. 

The switches are a bit of a pain, but the inside is fun to look at. I even posted a picture of one particularly "innovative" bit of mine.

Given the capacitor-like things are nuvistor valves, and there is interesting very exposed metalwork inside, be careful where you put your finger/probe/screwdriver

[tautech]

Sleep might help the thinking but it won't help the nearly 70mm of floating PCB/LCD above the screws. There is room where the Fluke and Martel logos sit to have added two more screws so it is either an ego Branding or dumb dumb engineering fail. Adding a wedge to the slots in the case insert might help keep the board in place.

As it is usable I won't be rushing into a new LCD. But interesting they are available off the shelf in Oz from their service agent shows them to be a failure point.

Would a pedestal under the Atmel chip give enough support ?

[beanflying]

Sleep might help the thinking but it won't help the nearly 70mm of floating PCB/LCD above the screws. There is room where the Fluke and Martel logos sit to have added two more screws so it is either an ego Branding or dumb dumb engineering fail. Adding a wedge to the slots in the case insert might help keep the board in place.

As it is usable I won't be rushing into a new LCD. But interesting they are available off the shelf in Oz from their service agent shows them to be a failure point.

Would a pedestal under the Atmel chip give enough support ?

It is more the reverse needed as the Atmel faces the LCD. The white clips on the LCD frame are all that keeps the zebras tight. So forcing the PCB low and wedging the LCD high is worth a go. I have some 4 thou Mylar sheet so I can jack the LCD in small increments and see if it helps providing I can get the PCB to stay in place with the limited supports.

[tautech]

Sleep might help the thinking but it won't help the nearly 70mm of floating PCB/LCD above the screws. There is room where the Fluke and Martel logos sit to have added two more screws so it is either an ego Branding or dumb dumb engineering fail. Adding a wedge to the slots in the case insert might help keep the board in place.

As it is usable I won't be rushing into a new LCD. But interesting they are available off the shelf in Oz from their service agent shows them to be a failure point.

Would a pedestal under the Atmel chip give enough support ?

It is more the reverse needed as the Atmel faces the LCD. The white clips on the LCD frame are all that keeps the zebras tight. So forcing the PCB low and wedging the LCD high is worth a go. I have some 4 thou Mylar sheet so I can jack the LCD in small increments and see if it helps providing I can get the PCB to stay in place with the limited supports.

Hmmm, understood. It's enough to drive you to drink but a clear head is heeded for a lasting fix.
Sleep then coffee should help. 

[Specmaster]

Yah, just had comfirmation that my Thurlby 1905A bench meter is out for delivery today and is currently only 63 deliverys away.....

[med6753]

Good advice.

Certainly a pain. All Flukes seem to suffer LCD problems 

I noticed that when Heathkit ripped off the Fluke 8021 they used a standard LCD module with standard pin layout. The side effect of this is you can still get exactly the same module. While I like some of the custom LCDs we’re an in age now where everything should have standard matrix LCD modules and all the fun stuff done in software.

But they don't suffer from ruby red LED issues. 

[med6753]

I found the issue with this 8800A and the wild readings on the 200V range. Extremely dirty switch contacts. Took several applications of Deoxit D5 to clear it up. So far it's working. If it continues to work fine....if not....I'm prepared to sacrifice the drifty 8810A as a parts mule. But we'll monitor it.

Today's objective is a complete calibration check of both 8800A's.

[Specmaster]

Good advice.

Certainly a pain. All Flukes seem to suffer LCD problems 

I noticed that when Heathkit ripped off the Fluke 8021 they used a standard LCD module with standard pin layout. The side effect of this is you can still get exactly the same module. While I like some of the custom LCDs we’re an in age now where everything should have standard matrix LCD modules and all the fun stuff done in software.

But they don't suffer from ruby red LED issues. 

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

[med6753]

Good advice.

Certainly a pain. All Flukes seem to suffer LCD problems 

I noticed that when Heathkit ripped off the Fluke 8021 they used a standard LCD module with standard pin layout. The side effect of this is you can still get exactly the same module. While I like some of the custom LCDs we’re an in age now where everything should have standard matrix LCD modules and all the fun stuff done in software.

But they don't suffer from ruby red LED issues. 

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

As far as I know most Fluke LED's are generic and readily available.

[bd139]

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

Don't worry - they're still available and quite cheap!

https://www.ebay.co.uk/itm/273992960208

Plus the type of module is a simple multiplexed one so with a couple hours in Kicad and a JLCPCB order you could retrofit different displays easily.

There's nothing nasty in the 1905A AFAIK. Even CPU is a 6502 + 6522 VIA + EPROM + normal 74LS  .

edit: the front panel / keyboard looks like the only risk.

[med6753]

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

Don't worry - they're still available and quite cheap!

https://www.ebay.co.uk/itm/273992960208

Plus the type of module is a simple multiplexed one so with a couple hours in Kicad and a JLCPCB order you could retrofit different displays easily.

There's nothing nasty in the 1905A AFAIK. Even CPU is a 6502 + 6522 VIA + EPROM + normal 74LS  .

edit: the front panel / keyboard looks like the only risk.

And since it's British made you'll probably need them. 

(exiting before the lynch mob catches me  )

[factory]

While both the HP34401 and the 34410/1 have been subject of many posts, even comparing them, has anyone here had experience of working with the 34465A? There are tempting offers, albeit from far away places out there!

I am slightly annoyed by the fact that you can only find overviews within a generation of instruments. I would really like to see HPAK gear getting such a complete, reliable and useful treatment as the Tektronix products are getting on TekWiki.

Btw, there is another one of the Thurlby DMMs upcoming.

If thats the one on eBay UK, then be aware that it looks like it has display issues with segments of the LEDs not lighting up.

Could it be the due to the camera shutter settings & the display being multiplexed? , the description doesn't mention anything about display problems.

David

[Specmaster]

Yeah it could be due to camera settings, I had the option of getting either one, I chose the slightly dearer one which photographed perfectly and looks the best overall condition, almost mint infact.

[Specmaster]

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

Don't worry - they're still available and quite cheap!

https://www.ebay.co.uk/itm/273992960208

Plus the type of module is a simple multiplexed one so with a couple hours in Kicad and a JLCPCB order you could retrofit different displays easily.

There's nothing nasty in the 1905A AFAIK. Even CPU is a 6502 + 6522 VIA + EPROM + normal 74LS  .

edit: the front panel / keyboard looks like the only risk.

Thats a great releif, I read it somwhere in a review or repair thread about them being unobtainable but those on eBay are the right ones 

[bd139]

My new Thurlby has ruby red LED's and I sure hope that it dosent have any issues with them as its game over then as they are obsolete specials 

Don't worry - they're still available and quite cheap!

https://www.ebay.co.uk/itm/273992960208

Plus the type of module is a simple multiplexed one so with a couple hours in Kicad and a JLCPCB order you could retrofit different displays easily.

There's nothing nasty in the 1905A AFAIK. Even CPU is a 6502 + 6522 VIA + EPROM + normal 74LS  .

edit: the front panel / keyboard looks like the only risk.

And since it's British made you'll probably need them. 

(exiting before the lynch mob catches me  )

So true. We even take the piss out of ourselves over it:

[bd139]

So blue PLA arrived  . Printing NanoVNA case!

[Ditiris]

Time to discovering EEVblog to dropping $3k on test equipment - almost a month. I'm proud of myself for resisting that long.

[AVGresponding]

And since it's British made you'll probably need them. 

(exiting before the lynch mob catches me  )

Oi !  Blooming cheek...

I'm not a fan of this type of membrane keyboard myself, but it seems to work fine.
Only thing I would mention, is that the header has 1 more pin than the cable connector, so make sure you observe which end has the extra one if you disconnect it...


EDIT:

Time to discovering EEVblog to dropping $3k on test equipment - almost a month. I'm proud of myself for resisting that long.

Only $3k? You're not trying hard enough...