Fluke 8400A; No display.

[neo]

I just got my 8400A after a fed ex screw up or two, no worries it arrived intact just delayed slightly.

Only problem is i get it and the display doesn't light up, i know HV is present because the + lights up on DCV and it appears to work as part of the display changes as i change inputs.

The only thing that does not work it seems are the actually numeric part of the display, i know one or two tubes could be bad but all of the except for the +- seems unlikely to me.

It appears some of the transistors got very hot at some point, see pictures,

This thing appears to have been sitting on a shelf since the 80s judging by the amount of dust, mild rust and or corrosion but nothing that should be an immediate issue.

Also it was made sometime in early '73 judging by the date codes.

I know it is not a factory dud due to the 5 calibration stickers on it, 4 local and 1 from fluke.

Also of note it has from the factory, Ac converter, OHMs converter, Data output unit (DOU), Remote control unit (RCU) and Rear input. someone later added the card for DC external reference (DC-ER)

There is only one unfilled card slot and two missing options, does this mean someone also added the RMS converter? Crazy as it may sound i would prefer it if it measured peak to peak AC.

I can't find the 8400A manual for free though I can find the 8300A one, can it be used or should i just buy the 8400A manual?

I would greatly appreciate help, hints or even a general clue what to look for. 

P.S. It is only 6 digit nixie tube meter, not 6.5 digit.

EDIT: For typos.

[Specmaster]

Oh dear thats bad news. It might help everyone if you could resize your photos to something like 800 x 600 pixels at least, it gives everyone chance to study them and see if they can spot anything to assist you.

[neo]

Will do, was just worried they wouldn't all fit was all. Its very apt that your the first poster, with that signature i mean, my name may not be Murphy but it may as well be with my luck.

[neo]

A thought occurs to me, one just went onto ebay for 80 (less than i paid for mine) with a shown working display, if i can get the wallet to agree with me would it be wrong to choose the easier path and buy that one?

[neo]

Also of note with the DOU out, if it is set to ac and turned on it will display either a 0 or 1 on the furthest left digit.

Also the sample rate light does not flash, i presume it is meant to.

While messing with the cards to see if anything changes the AC converter and another set of wries popped off the little block they were on, does it matter where they go? I assume it does but due to accident i didn't have chance to take note.

[Specmaster]

Will do, was just worried they wouldn't all fit was all. Its very apt that your the first poster, with that signature i mean, my name may not be Murphy but it may as well be with my luck.

Yeh, well you know what Dave says, "Murphy will get you every time" and hence my signature reflects how my lucks goes at times too.

To keep the size of the post down if you have loads of photos to post, you could use a site like Flickr or Imgur, post your photos there and then insert the links to them in your message and they appear as if they are part of your message rather than attachments and also there is no restrictions on file size either as they are not stored on this server and thus using bandwidth, if you notice posts by bd139, he uses this method as well. I do as well if I need to show details.

[Specmaster]

Also of note with the DOU out, if it is set to ac and turned on it will display either a 0 or 1 on the furthest left digit.

Also the sample rate light does not flash, i presume it is meant to.

While messing with the cards to see if anything changes the AC converter and another set of wries popped off the little block they were on, does it matter where they go? I assume it does but due to accident i didn't have chance to take note.

I assume you meant wires popped off, and I would say yes it does matter and without a service manual, I would not attempt to reconnect them incase Murphy really does get you. 

[neo]

Also of note with the DOU out, if it is set to ac and turned on it will display either a 0 or 1 on the furthest left digit.

Also the sample rate light does not flash, i presume it is meant to.

While messing with the cards to see if anything changes the AC converter and another set of wries popped off the little block they were on, does it matter where they go? I assume it does but due to accident i didn't have chance to take note.

I assume you meant wires popped off, and I would say yes it does matter and without a service manual, I would not attempt to reconnect them incase Murphy really does get you. 

i believe i said that they popped off.

[Specmaster]

You did indeed but you said "While messing with the cards to see if anything changes the AC converter and another set of wries popped off the little block they were on, does it matter where they go? I assume it does but due to accident i didn't have chance to take note." I have no idea what block you are referring to hence I said I wouldn't reconnect them without the service manual.

[neo]

You did indeed but you said "While messing with the cards to see if anything changes the AC converter and another set of wries popped off the little block they were on, does it matter where they go? I assume it does but due to accident i didn't have chance to take note." I have no idea what block you are referring to hence I said I wouldn't reconnect them without the service manual.

Fair point in my excitement/ annoyance i was little non specific.

To see if anything changed drastically i started take cards out, with the AC converter and another board i can't remember the name of right now their wires popped off this little grey block which seems to distribute the signal input from the front panel.

Now in hindsight i know i should have taken notes to, but i didn't think too. I asked just to query if it was common knowledge in any way.

[Specmaster]

No, its not, I have the Fluke 8505A (just discovered that above 4M it is miles out of calibration) have you searched for a manual?

[neo]

Only one i have found is 12 for digital of 15 for paper, truth be told i prefer paper. Though i'm considering getting another 8400A with a known working display

[Specmaster]

I'd get a digital (pdf) then you can print it out hundreds of times and also make multiple copies of the files and store it various drives, USB sticks, NAS drives and of course CD's in case you accidentally erase it. Get the paper one and anything happens to you're screwed.

[neo]

Only problem is the digital is Artek, from what i know they use heavy copy righting.

[Specmaster]

They do copyright the pages is true, but why would that worry you? You can still make as many copies and prints as you like, you could also give away the odd copy if you can trust the person who you give it to not to pass it onto anyone who is likely to post it on a forum so that that it can be traced back to you. In reality I doubt if they would mind if you did give the odd copy away, as its advertising their services for the manuals that the recipient can't cadge from anyone else isn't it?

If you paid for an original manual in paper format, the same is true, you could photocopy and give it away if you so wished. 

[Specmaster]

I attach a couple of pages from a manual I purchased from them, they are very fair as well, as you see from page 2, should your copy become corrupted or lost in a disc crash etc, they will replace it for you.

The copyright is not intrusive either.

[neo]

I attach a couple of pages from a manual I purchased from them, they are very fair as well, as you see from page 2, should your copy become corrupted or lost in a disc crash etc, they will replace it for you.

The copyright is not intrusive either.

Between your recommendation and the fact that i get it immediately, you have convinced me.

[Specmaster]

Glad I could help 

[neo]

Glad I could help 

Just talking me through the problem helps, just the way my brain works. 

[NeedsMoreFlux]

I might have another transistor/thermistor. I have alot from old ham radios. If that one isn't functioning properly let me know. I might have one.

[neo]

I might have another transistor/thermistor. I have alot from old ham radios. If that one isn't functioning properly let me know. I might have one.

i'll let you know, thanks for the offer.

[Cubdriver]

A thought occurs to me, one just went onto ebay for 80 (less than i paid for mine) with a shown working display, if i can get the wallet to agree with me would it be wrong to choose the easier path and buy that one?

Oh, crap - I think I just bought that one.     (Though in my defense, I'd been watching it for over a week after initially learning of the model when you bought yours.)

-Pat

[neo]

A thought occurs to me, one just went onto ebay for 80 (less than i paid for mine) with a shown working display, if i can get the wallet to agree with me would it be wrong to choose the easier path and buy that one?

Oh, crap - I think I just bought that one.     (Though in my defense, I'd been watching it for over a week after initially learning of the model when you bought yours.)

-Pat

I don't mind Pat, if you wanted one and got it then good on you. I would of just used it to take the easier path.

So instead of sniping something from under me you simply removed temptation from my path 

[Cubdriver]

A thought occurs to me, one just went onto ebay for 80 (less than i paid for mine) with a shown working display, if i can get the wallet to agree with me would it be wrong to choose the easier path and buy that one?

Oh, crap - I think I just bought that one.     (Though in my defense, I'd been watching it for over a week after initially learning of the model when you bought yours.)

-Pat

I don't mind Pat, if you wanted one and got it then good on you. I would of just used it to take the easier path.

So instead of sniping something from under me you simply removed temptation from my path 

So I helped to save you from yourself?     Ok, I can live with that.   

-Pat

[neo]

As far as i can tell the problem with mine is just that it doesn't display, i think something has gone screwy in the analog to digital converter.

The furtherest left digit with flash between 0 and 1 occasionally while playing with the range buttons and from that and the + i know HV is present.