Author Topic: FREE: 3 China made VFD displays for the Agilent 34401A (Read 9855 times)

HighVoltage · « **on:** July 12, 2018, 10:22:00 am »

ALL SOLD !

I bought three (3) new VFD displays from China.
They work, but the brightness is low and I don't like them.

But on the other hand, they are too good for the trashcan.
So, if anyone in Germany wants them, you can have all three for free, including free shipping.
Outside of Germany, please pay shipping cost.

May be good for someone playing around with VFD's
Don't expect too much from this China product.

Zucca · « **Reply #1 on:** July 12, 2018, 11:00:33 am »

HighVoltage · « **Reply #2 on:** July 12, 2018, 11:57:02 am »

Sold, pending shipping payment from another country

Zucca
That is very funny.
The products from China are getting better and better in general.

CJay · « **Reply #3 on:** July 12, 2018, 12:19:55 pm »

Quote from: HighVoltage on July 12, 2018, 11:57:02 am

Sold, pending shipping payment from another country

Zucca
That is very funny.
The products from China are getting better and better in general.

Always makes me laugh, Japan used to have the reputation China has now, give it another 15-20 years and it'll be Vietnesium or some other developing country with China being the mark of quality.

COSMOS2K · « **Reply #4 on:** July 12, 2018, 01:11:49 pm »

Hello:
Chinese products while falsifying, stealing and cheating buyers as they are currently doing will never reach the scrap rating, they will remain garbage.

Greetings.

CJay · « **Reply #5 on:** July 12, 2018, 01:35:30 pm »

Quote from: COSMOS2K on July 12, 2018, 01:11:49 pm

Hello:
Chinese products while falsifying, stealing and cheating buyers as they are currently doing will never reach the scrap rating, they will remain garbage.

Greetings.

Thing is, they don't have that reputation now, chances are you're using a Chinese made device to read this message on.

Zucca · « **Reply #6 on:** July 12, 2018, 01:51:45 pm »

No because of this:

https://www.eevblog.com/forum/repair/vintage-parts-from-china/msg1609819/#msg1609819

I only buy from china if a friend tell me to buy it, or I read a good review from someone I trust.
For example, since the T12 iron crap clones OLED did not had nice reviews, I just went ahead and got a nice used PS-800 Metcal.
Between new fantastic on paper device made in chinesium and a good old used one, I chose the second even if it is more expensive.

I see that they are getting better, but you need to think triple times as much before pressing the button "buy" in china www

HighVoltage · « **Reply #7 on:** July 12, 2018, 02:02:24 pm »

OK, sold and shipped to a nice forum member.

My first hand experience with China is, that they constantly increase quality
and one day in the not so far distance, they will be like western countries.

TiN · « **Reply #8 on:** July 12, 2018, 04:56:12 pm »

Customers get what they want to pay for, no matter the country of the manufacture.

.

tszaboo · « **Reply #9 on:** July 12, 2018, 04:59:54 pm »

They make replacement displays for the 34401A? Is there a market big enough for this. wow.

PlainName · « **Reply #10 on:** July 12, 2018, 05:07:01 pm »

Quote

I only buy from china if ...

So how do you know they are (still) crap?

HighVoltage · « **Reply #11 on:** July 13, 2018, 08:56:35 am »

Yes, I was surprised too and that is why I did not hesitate to order 3 pieces.
But they also copied the Agilent GPIB to USB adapter and flooded the market.

I would think that there is a little bit more involved, making a working VFD.
May be development cost is low in China.

CJay · « **Reply #12 on:** July 13, 2018, 10:17:11 am »

Custom VFDs aren't too big a deal if you need a few of them but wasn't there a Chinese lookalike of the 34401, a Victor or something, possibly that's where they're from?

sn4k3 · « **Reply #13 on:** July 13, 2018, 05:36:55 pm »

Thats why price is cheap, almost everything is made in china, but used components or the quality is not china fault, that is a decision from the manufacture or from the design. The same factory can produce original grade products and crappy clones, they want profit not good stuff with low profit. They also degrade quality by steps so when you buy replacements of replacements you will not notice a big change, change from 9 to 1 is big change, but if they do that at steps like 9,8,7,6 and you itenerate all steps you won't notice that huge difference which become a good profit for them, this happen on copy phone LCDs for example where price go lower and lower with time
iPhone is made on a china factory with high grade components, still apple can decide to use low grade components instead, that's not a problem from China, the developer decide the product quality not china. That doesn't mean iPhone is good anyway

Now things that are made in china from china requested by a bussiness man to make some sells still a problem from that guy who requested that stuff to be made and not from China (Country)
I bet any country can produce really crap stuff if they want as good stuff as well, is all a matter of money/profit or a end

PS: I buy lot of products from china, and i found some are really good, others are crap, still my experience is much more positive than otherwise.

janoc · « **Reply #14 on:** July 13, 2018, 05:51:20 pm »

These VFDs are just fine, I have one in my meter for over a year now and no complaints (at least I assume that there aren't multiple versions of it).

I do love the clowns that jump into every thread mentioning China with "insightful" comments about counterfeiting, crap quality, IP theft and what not, even though they have obviously never seen or used the product in question. Especially when there is no other source for these displays apart from eBay or cannibalizing other meters because Keysight has stopped supporting these. They may still have a few of the complete display modules available but those are much more expensive - and the question is how much longer will they last, I don't think Keysight is making any more of those.

Guys, can you cut the BS out, please?

CJay · « **Reply #15 on:** July 13, 2018, 06:54:26 pm »

Quote from: janoc on July 13, 2018, 05:51:20 pm

These VFDs are just fine, I have one in my meter for over a year now and no complaints (at least I assume that there aren't multiple versions of it).

I do love the clowns that jump into every thread mentioning China with "insightful" comments about counterfeiting, crap quality, IP theft and what not, even though they have obviously never seen or used the product in question. Especially when there is no other source for these displays apart from eBay or cannibalizing other meters because Keysight has stopped supporting these. They may still have a few of the complete display modules available but those are much more expensive - and the question is how much longer will they last, I don't think Keysight is making any more of those.

Guys, can you cut the BS out, please?

It really pisses me off, there's always someone who pops up with the 'Chinesium' thing.

Get what you pay for, if you want quality, China will sell it to you, if you want crap, they'll sell you that too.

Guess why so many countries have a huge trade deficit with China...

Mr. Scram · « **Reply #16 on:** July 13, 2018, 11:21:27 pm »

Highvoltage, how did you test the brightness? Did you do this in the device or in a test setup?

HighVoltage · « **Reply #17 on:** July 14, 2018, 12:01:27 pm »

Quote from: Mr. Scram on July 13, 2018, 11:21:27 pm

Highvoltage, how did you test the brightness? Did you do this in the device or in a test setup?

I installed 2 of the three VFDs in one 34401A that I had laying around.
The original display has really nicely and evenly distributed brightness
This particular China version had the brightness very unevenly distributed.

I bought other VFDs from China before and they were very good.

On ebay, I found another vendor in China and ordered a few more VFDs.

janoc · « **Reply #18 on:** July 14, 2018, 06:10:22 pm »

That's sounds like you got unlucky and got a bad/poor specimen. Mine is fairly even.

Just make sure to tape over the exposed electrodes on the sides. The original Keysight VFD has them covered, these Chinese ones don't and it could cause shorts against the metal frame holding the VFD in place. That could theoretically cause the uneven brightness as well.

exe · « **Reply #19 on:** July 16, 2018, 11:36:02 am »

Sorry for asking, but did you clear the flux?

HighVoltage · « **Reply #20 on:** July 16, 2018, 12:23:18 pm »

Quote from: exe on July 16, 2018, 11:36:02 am

Sorry for asking, but did you clear the flux?

Oh, yes, I did clear the flux.
This is not the first Agilent VFD I have installed.

Over the years I replaced a lot of VFD's on the 34401A and other Agilent instruments.
This was the first bad experience.

exe · « **Reply #21 on:** July 16, 2018, 03:04:42 pm »

Quote from: HighVoltage on July 16, 2018, 12:23:18 pm

Over the years I replaced a lot of VFD's on the 34401A and other Agilent instruments.
This was the first bad experience.

Was the VFD new? No traces of previous soldering? Is it possible the driver is bad? (I had a bad driver on my K2000, one segment was dead, but with uncleaned flux and wrong wiring I could get similar problems with uneven brightness).

HighVoltage · « **Reply #22 on:** July 16, 2018, 07:00:31 pm »

Yes, the VFD'S were brand new with no previous soldering on the pins.
This was just a cheaply made copy.

I ordered a new VFD from China and when it is installed, I will post some pictures.
I am sure it will work perfectly.

macboy · « **Reply #23 on:** July 17, 2018, 03:49:28 pm »

The dim display and especially the uneven brightness looks very much like the symptoms of an under-driven cathode filament. Perhaps the replacement display's filament wires have a higher resistance and therefore are not getting enough current to emit sufficient electrons. You could try measuring the current, and if it is lower than the original, boost it up (usually there are some resistors in series with the filament, making this easy to do). You'll be surprised what a difference that can make.

floobydust · « **Reply #24 on:** July 17, 2018, 04:06:35 pm »

Which vendor did you get the duds from?

The displays are made by Zhejiang Feida and should have a QC sticker on the back. P/N FD33-1201

I'd contacted Noritake iTron about the VFD and they had concerns because the VFD design is owned by HP/Agilent/Keysight.
The MOQ... and that idea stalled getting Keysight to release the datasheets or drawings.

Samsung made them next and that's probably where the design got into the hands of the chinese

janoc · « **Reply #25 on:** July 17, 2018, 05:26:53 pm »

Quote from: macboy on July 17, 2018, 03:49:28 pm

The dim display and especially the uneven brightness looks very much like the symptoms of an under-driven cathode filament. Perhaps the replacement display's filament wires have a higher resistance and therefore are not getting enough current to emit sufficient electrons. You could try measuring the current, and if it is lower than the original, boost it up (usually there are some resistors in series with the filament, making this easy to do). You'll be surprised what a difference that can make.

Unlikely - that wouldn't manifest itself only in certain localized segments (e.g. one digit) being brighter than another. If there is not enough current through the filament, the entire display would be dim or maybe one row of segments served by a certain filament wire (but I believe all the wires are connected together so there shouldn't be differences in current) and not one digit while the adjacent ones are fine.

HighVoltage · « **Reply #26 on:** July 19, 2018, 07:01:48 pm »

Quote from: macboy on July 17, 2018, 03:49:28 pm

The dim display and especially the uneven brightness looks very much like the symptoms of an under-driven cathode filament. Perhaps the replacement display's filament wires have a higher resistance and therefore are not getting enough current to emit sufficient electrons. You could try measuring the current, and if it is lower than the original, boost it up (usually there are some resistors in series with the filament, making this easy to do). You'll be surprised what a difference that can make.

I am sure a new good VFD will work perfectly in this instrument.
Once I have the new and original display installed, I will post some pictures here.

HighVoltage · « **Reply #27 on:** July 19, 2018, 07:07:55 pm »

Quote from: floobydust on July 17, 2018, 04:06:35 pm

Which vendor did you get the duds from?

The displays are made by Zhejiang Feida and should have a QC sticker on the back. P/N FD33-1201

I'd contacted Noritake iTron about the VFD and they had concerns because the VFD design is owned by HP/Agilent/Keysight.
The MOQ... and that idea stalled getting Keysight to release the datasheets or drawings.

Samsung made them next and that's probably where the design got into the hands of the chinese

Yes, the original manufacturers are iTron and Samsung.
I have used both of these good brands before and never had any problems.

The China vendor that I bought the bad VFDs from, is no longer listed, LOL!

But these look also to be bad clones and are NOT recommended:

Vacuum Fluorescence Fluorescent Display Screens VFD For HP/AGILENT 34401A New
EUR 45,69
https://www.ebay.de/itm/131861099316

Vacuum Fluorescence Fluorescent Display Screens VFD For HP/AGILENT 34401A New
EUR 48,18
https://www.ebay.de/itm/263536502662

Vakuum Fluoreszenz Fluorescent Display Bildschirme VFD für HP/Agilent 34401A NEU
EUR 37,35
https://www.ebay.de/itm/263768913587

meandeev · « **Reply #28 on:** July 22, 2018, 09:06:34 pm »

Before this thread was started, I ordered a cheap VFD via ebay https://www.ebay.de/itm/Vacuum-Fluorescence-Fluorescent-Display-Screens-VFD-For-HP-AGILENT-34401A-New/263768913587 for $43,49.

And I got the clone that you have shown in your pictures. At a first glance it looks not good: bended pins (was shipped in a small bunch of foam), splintered glass at some corners and so on.

But I was lucky, because the display is bright and looks good!
So it seems there are huge differences in quality of the clones.

Seems these VFD´s are made of real "chinesium" : It has no defined characteristics, you never know what you will get, even if you buy at the same shop.

bitseeker · « **Reply #29 on:** July 23, 2018, 05:31:19 am »

Quote from: janoc on July 17, 2018, 05:26:53 pm

Quote from: macboy on July 17, 2018, 03:49:28 pm
The dim display and especially the uneven brightness looks very much like the symptoms of an under-driven cathode filament. Perhaps the replacement display's filament wires have a higher resistance and therefore are not getting enough current to emit sufficient electrons. You could try measuring the current, and if it is lower than the original, boost it up (usually there are some resistors in series with the filament, making this easy to do). You'll be surprised what a difference that can make.

Unlikely - that wouldn't manifest itself only in certain localized segments (e.g. one digit) being brighter than another. If there is not enough current through the filament, the entire display would be dim or maybe one row of segments served by a certain filament wire (but I believe all the wires are connected together so there shouldn't be differences in current) and not one digit while the adjacent ones are fine.

I agree with you, janoc. The pattern of dimness looks like it's been left on in the default 5.5-digit mode.

If the pins on that one were pristine, it's pretty bizarre, as if the pins had been replaced on a used VFD.

KE5FX · « **Reply #30 on:** July 23, 2018, 06:11:19 am »

"We will sell you the rope you use to hang yourselves. Fortunately for you, it will probably break."

In all seriousness, I'm old enough to remember my dad saying exactly the same things about Japan in the 1970s. Cheap-ass junk! Nothing but cut-rate copies of superior Western engineering. They'll never amount to anything. Defective culture, bunch of bushwhacking yellow barbarians. (He was a WWII Pacific vet.) No creative drive, no originality, nothing but counterfeit crap.

So it's easy for me to avoid making the same mistaken assumptions about China. As CJay says, they'll sell you crap if that's what you're willing to pay for... or good stuff if that's what you're willing to pay for.

HighVoltage · « **Reply #31 on:** July 23, 2018, 08:41:46 am »

Quote from: meandeev on July 22, 2018, 09:06:34 pm

But I was lucky, because the display is bright and looks good!
So it seems there are huge differences in quality of the clones.

Seems these VFD´s are made of real "chinesium" : It has no defined characteristics, you never know what you will get, even if you buy at the same shop.

How interesting.
May be I order one more and get lucky as you!

Well there are some products from China that I am astonished of the quality.
For instance my OnePlus 5T smart phone.
Just amazing

May be one day when we read "Made in China" we look at this as pure high end quality.
BTW, the slogan "Made in Germany" was originally a punishment by the British to show to the world, how bad German manufacturing was.

CJay · « **Reply #32 on:** July 23, 2018, 10:31:24 am »

Quote from: HighVoltage on July 23, 2018, 08:41:46 am

Quote from: meandeev on July 22, 2018, 09:06:34 pm

But I was lucky, because the display is bright and looks good!
So it seems there are huge differences in quality of the clones.

Seems these VFD´s are made of real "chinesium" : It has no defined characteristics, you never know what you will get, even if you buy at the same shop.
How interesting.
May be I order one more and get lucky as you!

Well there are some products from China that I am astonished of the quality.
For instance my OnePlus 5T smart phone.
Just amazing

May be one day when we read "Made in China" we look at this as pure high end quality.
BTW, the slogan "Made in Germany" was originally a punishment by the British to show to the world, how bad German manufacturing was.

I'd be interested to know about that, it's always been my understanding that German engineering was excellent (and, as much as I hate to bring this up, partly to blame for supply issues in WW2 because quality and finish was making production slow)

HighVoltage · « **Reply #33 on:** July 29, 2018, 12:00:58 pm »

The journey continuous...

As explained before, I ordered a new display from a different seller in China.
This time it was more expensive $65 + $10 shipping.
And this time the seller clearly showed the SAMSUNG branded VDF in the pictures.
And what did I get ....

China Junk again, this time packed so badly, that even one pin was broken off.

First three pictures are out of the eBay offer.
Last three pictures are of what I received yesterday.

janoc · « **Reply #34 on:** July 30, 2018, 03:12:02 pm »

Ouch ... That's really unlucky. Mine was packed much better than this.

Zucca · « **Reply #35 on:** July 30, 2018, 03:38:38 pm »

Fortunately there is a qu1ck solution coming soon.

bitseeker · « **Reply #36 on:** July 31, 2018, 02:33:34 am »

Quote from: HighVoltage on July 29, 2018, 12:00:58 pm

The journey continuous...

As explained before, I ordered a new display from a different seller in China.
This time it was more expensive $65 + $10 shipping.
And this time the seller clearly showed the SAMSUNG branded VDF in the pictures.
And what did I get ....

China Junk again, this time packed so badly, that even one pin was broken off.

First three pictures are out of the eBay offer.
Last three pictures are of what I received yesterday.

Ugh! That sucks. I've been tempted to change my VFD, but it seems the risk is too high. My display is still readable, it's just uneven (i.e., you can see what resolution and mode it was operating in). So, it's not good for OCD, but usable otherwise.

Quote from: zucca on July 30, 2018, 03:38:38 pm

Fortunately there is a qu1ck solution coming soon.

Yes, his project is the long-term solution.

exe · « **Reply #37 on:** July 31, 2018, 05:03:49 am »

BTW, what is the lifespan of a VFD display? I noticed that I don't use my K2000 because I'm worried to wear the display (and no replacement is available anymore). But that is sort of silly: it now lays on the bench and collects dust.

bitseeker · « **Reply #38 on:** July 31, 2018, 07:05:01 am »

It'd depend on the particular module, how hard it's driven (i.e., brightness), hours used per day, etc. Since my VFD equipment is all used, I don't know what their run time has been.

The VFD in my kitchen microwave has been showing its clock 24x7 for the past 20 years and it's still legible from across the room. Up close, you can tell it has faded compared to annunciators that are rarely lit, but I'm quite surprised by its longevity.

If you use a DMM for a few minutes or hours a day, a few times a week, you'd probably not even notice degradation for a long while. For long-duration data logging, some (many?) bench DMMs can turn off their display via remote command (e.g., DISPlay OFF is the SCPI command on the HP 34401A).

HighVoltage · « **Reply #39 on:** July 31, 2018, 10:22:57 am »

After I complained to the seller, I got at least the money back for the latest item.

Today I bought a genuine VFD with attached PCB from Keysight:

Part Number: 34401-66522
Price: EUR 122.00

The part should arrive within one week.

janoc · « **Reply #40 on:** July 31, 2018, 02:44:09 pm »

Quote from: exe on July 31, 2018, 05:03:49 am

BTW, what is the lifespan of a VFD display? I noticed that I don't use my K2000 because I'm worried to wear the display (and no replacement is available anymore). But that is sort of silly: it now lays on the bench and collects dust.

Under normal hobby use a VFD will most likely outlast the rest of the instrument. The main issue with these meters is that they were often stuck in measurement racks doing automated data logging, with the displays on 24/7 for years. That will wear them out eventually. Then when you buy a meter like that from eBay you discover that the display is very dim.

Unless you are planning to use it like that (and then the display can be turned off via GPIB!), you have little to worry about.

klaus11 · « **Reply #41 on:** August 02, 2018, 04:54:35 pm »

I'm looking for LCD screen Fluke PM6690. You know some kind of information.

HighVoltage · « **Reply #42 on:** August 03, 2018, 09:11:39 am »

Quote from: klaus11 on August 02, 2018, 04:54:35 pm

I'm looking for LCD screen Fluke PM6690. You know some kind of information.

I used to have a PM6690 but sold it a long time ago.
But there might be some forum members that still have one and know where to get the display.
May be you want to open a request for that to get more attention.

There are also a few threads on the PM6690 here on the forum
https://www.eevblog.com/forum/testgear/fluke-pm6690-12-digits-frequency-counter/

klaus11 · « **Reply #43 on:** August 03, 2018, 09:51:27 am »

Thank you.

Jwalling · « **Reply #44 on:** August 03, 2018, 10:24:52 pm »

Anything would be better than this one:
https://www.ebay.com/itm/HP-Agilent-34401-66512-Display-Assembly/173449311172?
"Appears to be in excellent condition."

bitseeker · « **Reply #45 on:** August 03, 2018, 10:28:04 pm »

Is that just glare on the screen or is its vacuum compromised?

Jwalling · « **Reply #46 on:** August 03, 2018, 11:26:11 pm »

Quote from: bitseeker on August 03, 2018, 10:28:04 pm

Is that just glare on the screen or is its vacuum compromised?

Vacuum. The getter turns white.

bitseeker · « **Reply #47 on:** August 04, 2018, 12:03:47 am »

Yeah, it's on the right side for it to be the getter.

HighVoltage · « **Reply #48 on:** August 04, 2018, 08:48:39 am »

The Keysight parts arrived already and here are some pictures
This is how a genuine new VFD for the 34401A looks like

HighVoltage · « **Reply #49 on:** August 04, 2018, 09:13:07 am »

First test...
What a difference ...

HighVoltage · « **Reply #50 on:** August 04, 2018, 09:18:38 am »

And to make the unit like new, I also got a few new plastic parts

HighVoltage · « **Reply #51 on:** August 04, 2018, 09:28:13 am »

And a new Keysight Window as well

HighVoltage · « **Reply #52 on:** August 04, 2018, 12:30:14 pm »

After 1 hour warmup, the instrument is spot on and stable, without any movement on the display.

So, one thing is sure for me, I will not buy any more replacement VFD's from China.

HighVoltage · « **Reply #53 on:** August 04, 2018, 03:32:50 pm »

For Sale ...

The last VFD from China was soldered to the Agilent PCB .
It looks like the last segment is not lighting up.
This might be a problem with the PCB, one trace was broken and was repaired.
I will leave the pins long and don't clip them short.
And I will NOT clean up the solder spots.

If anyone is interested in these parts:

Euro 5 in Germany including shipping.
Euro 12 in EU
Outside of EU, ask

Parts included:
1x Original Agilent PCB with ribbon cable
1x China VFD installed
1x Agilent Window

As shown in these pictures.

SrS · « **Reply #54 on:** August 04, 2018, 04:39:38 pm »

If its still available I'm interested, shipment to NL.
I have a unit with dim display & wrong segments.

HighVoltage · « **Reply #55 on:** August 04, 2018, 04:42:57 pm »

OK, SrS, they are yours.
PM sent

bitseeker · « **Reply #56 on:** August 04, 2018, 05:57:05 pm »

Quote from: HighVoltage on August 04, 2018, 09:28:13 am

And a new Keysight Window as well

Wow! Really like new.

GigaJoe · « **Reply #57 on:** August 17, 2018, 07:18:57 pm »

Means ... all ebay's VFD for 34401A are not good at all, or for $40-50 it acceptable?

HighVoltage · « **Reply #58 on:** August 17, 2018, 09:00:53 pm »

Quote from: GigaJoe on August 17, 2018, 07:18:57 pm

Means ... all ebay's VFD for 34401A are not good at all, or for $40-50 it acceptable?

The highest price I paid was $65 and it was NOT good.
May be there are higher priced VFDs on ebay but I have not tested them.
I am very happy with the original VFD from Keysight

Bud · « **Reply #59 on:** August 17, 2018, 09:36:03 pm »

Quote from: HighVoltage on August 04, 2018, 12:30:14 pm

So, one thing is sure for me, I will not buy any more replacement VFD's from China.

This should be made a sticky on the front page of the forum.

And i'd take out the "replacement VFD's" part from it.


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Author Topic: FREE: 3 China made VFD displays for the Agilent 34401A (Read 9855 times)

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