Hioki 3532-50 LCR Repair (One major problem solved, SM still wanted)

[Martin72]

Hi at all,

Today a defective Hioki 3522-50 LCR meter arrived, bought it from ebay - Having eventually a 5 Mhz LCR sounds so sweet in my ears, I can´t withstand...
Optically it´s "so la la", technically:
Switched it on and indeed, nothing happens except a relais clicking is hearable from somewhere.
Examining the inside, one of the pcbs got a Batteryclip, the Battery is leaked out.
Voltages I didn´t check so far.
Question in the round:
Are there schematics or much better a service manual avaible ?

Martin

[Martin72]

Pics...
First shows the pcb with the "rotten" battery.
In the upper left corner, to my surprise there´s an inverter for the backlight of the LCD - Interesting.
I´ve wrote to hioki but hopes are low getting a suitable answer concerning any docs...
But you can´t know it when you´re not trying it.
Otherwise the usual steps for investigation will following on the next weekend.
I´ll report..

[coromonadalix]

Usuals checks  like the psu voltages

you should check under the corroded battery holder, if some traces have been damaged  ??

And sadly,  i doubt   Hioki will answer your requests,  ask them under an non disclosure agreement (NDA) ??

[Martin72]

Usuals checks  like the psu voltages

Of course, also what the layers towards the battery concerns.
Having a schematic makes it easier, but it´s not impossible without.
Tomorrow I desolder the batteryclip at work, I think I´ve found a one which will fit into.
Sometimes without a battery nothing will start, maybe I got luck.

And sadly,  i doubt  Hioki will answer your requests

Yes, hopes are low.
But I´ll try everything to fix it - Used ones(5Mhz versions like mine) are not avaible under 2000 bucks.

[coromonadalix]

Not sure if they keep some configurations with the cell battery, and if the battery dies,  you loose something

Or have an memory corruption ??   you best luck  would be to find this control board   easier said than done 

good luck

[TERRA Operative]

Did you write to Hioki Japan directly?

If you have no luck, I can contact them in Japanese. Sometimes that is more effective.

[Martin72]

I received an automatic answer from hioki.jp, so I think it´s the japan site.

If you have no luck, I can contact them in Japanese.

 

Tell you then.

[Martin72]

No response until this afternoon from hioki..
Maybe it smells "fishy" for them because I´ve filled out the contact formular in such manner they want you to do, with your company adress, department, email...
Maybe I´ve should wrote, it´s only for private usage....

Today the "proforma" batteryclip arrived from amazon, a capsuled one with leads - for first try it´s OK.
PCB itself didn´t got any further damages through the leakage, after cleaning the solder side it looks like new.
Tomorrow soldering the clip, new battery, then next attempt including measuring of the aux. voltages.
BTW...
You´ll never get one piece from amazon concerning articles like this - Anyone interested in 29 batteryclips with leads ?! 

[Martin72]

NEVER underestimate the meaning of a backup battery...It runs!
After assembling/soldering and turning on, nothing happens...I start measuring voltages, but after a while a system beep comes up.
Since then, turning off/on, always powered on, yeah !
But still I want to have the SM or at least a part list, because light won´t go on and the touchpanel won´t work proper anymore, because there´s air or moisture in a kind of moveable bubble inside.
Also the Display got a "dead" line, but hey....it works basically, really great.
To be continued...

[coromonadalix]

you have a dead backlight  it seems ??

For the touchscreen, never seen this kind with so many  pins,  for the bubble, it would need to slightly try to create a vent between the layers and gently push the bubble out,  unless it re create it ??

The problem is:   be careful, you have an flex trace going all the way around the touch, you must be very careful


And i dont see the lcd number markings ??  just an sed1335 lcd controller ic, on the main board,    it means the lcd as no main (brain)control logic, it has col and rows drivers ....

You have the cfl driver on the main board too

[Martin72]

you have a dead backlight  it seems ??

Actually I think so, but you got a menu where you could turn it on or off - when the panel would recognize my touch...
Try it out again, report.
Also pics from the display will follow...

[coromonadalix]

you where faster than me writting my previous thread  loll  i was editing some infos

For the lcd  it could be some zebra strips  with bad contacts   be sure you have nothing who touch  some drivers ic's on the lcd ....

This lcd should be easily dismantable, with rotated frame pins,  remove solder blobs who ground the black frame   ??

[Martin72]

Thank you for the advices 
I´m into test&repair since 20yrs but you´ll never know everything.
Interesting thing:

After unpowered for say a half hour, I´ve powered on again....Nothing.
Leave it to on...After say a minute or little more, system boots up.
Then when you turn off and on again, system boots up immediately...Whats going on..
Need a schematic...
Nevertheless, pics from the display will come soon.

[coromonadalix]

Maybe over time   not sure if you have some ram  corruption  or sluggyness

I had equipement with some ram failure, it was booting very slow,  but was perfectly functionning, changed the part, and bam it was speedy ??

Not sure of this one,  something could affect it's boot time,  but still seems to function normally after a while

And the usual suspects are  the supply lines, noises, spikes,  bad capacitors  ...


I would say to get an idea:  check every part number on the cpu board,  try to get their datasheet, and try to figure out some basic functions  like watchdog, reset circuitry etc ...


And  i doubt  Hioki will give an schematic, you may (and i hope not)  never get an service manual ??

 

[Martin72]

Yepp, will examine also the power lines which are going to the controller board with scope.
Maybe today, maybe tomorrow.
Here a dedicated pic of the LCD panel´s backside.
It´s from Powertip, model PG320240C

[coromonadalix]

thks  an 320 by 240   pixels  glcd   wow   some high prices  there, cheaper prices on Ebay

Not being rude,   you have an expensive puppy to repair  loll 

For the touch screen, i hope  you will be able to remove the bubble,  this one i'm not even sure you could find a substitute or even an original one ??   

With so many connector lines,  i would say it's a capacitive one, But some old resistive one had many connections

To be sure,  take a pen eraser and try to do functions,  resistive will work okay, capacitive  not.

Once again, it's to find every part datasheet to be sure, 

Lots of work ahead ??

[Martin72]

Absolute but I´m totally convinced about that it will be worth it.

[mawyatt]

Hioki provides very high quality instruments, maybe some of the best available from Japan, and they are expensive!!

Seems you've found a "Jewel in the Rough", hope you can return it to a useful life and be rewarded for your efforts 

Best,

[Martin72]

I got good hopes to fix it, but I also want to polish it in optically way after this.
I´ve payed 290€ for it, this is nothing for a 5Mhz Bridge (is it a bridge....).
It would be fantastic to get the SM or spare parts like the touchpanel or even the front.
The front is nearly yellow....

[Martin72]

Identified the chips on the controllerboard(and named them in the pic)
Actual mostly interesting is the battery control chip upper left.
Will measure it tomorrow, it controls resetting....

Martin

[coromonadalix]

Check ic108 a 3 pin sot,  near one of the ram, try to find what it is

the SED lcd controller  has a ram chip for itself

seem pretty simple logic  loll   lots are hidden in the fpga ....

Unlees the flash chip has began to deteriorate,   but you say it eventually work    I would still suspect the ram ic's  ??

With the datasheets,  you are able to measure many ic's vcc pins voltage(s)

Suprised to see somekind of a clock generator instead of a crystal ??

For the yellowish color,  there was some talk here   about whitening plastic / restoration  etc ... 

[Martin72]

Hi,

Tomorrow I´ll turn my scope on and doing some measures.
First the reset signal from the battery controller chip, then looking further.
It must be something which last a while, maybe a voltage to come up on the right level.
When it´s something with the RAM...As long as they are avaible I don´t care.
At work I got access to a rework station so this would be a minor problem.

Suprised to see somekind of a clock generator instead of a crystal ??

There´s a second oscillator on the main pcb.

For the yellowish color,  there was some talk here   about whitening plastic / restoration  etc ...

Good to read, post tomorrow a pic of the front panel.

[Martin72]

I´m coming closer to to the solution...
Not done scope measuring yet, but this will be the next, because:
The 5V voltage (I guess it is) from the supply starts with appx 4.2V (meter reading) and increase slowly, at appx 4.4V the system boots up because the battery control chip release the reset signal then.
This is not normal...
Next is watching the 5V signal how its look like - Unfortunately at later afternoon, part of the sunday is reserved for family.
Stay tuned.
Martin

[Martin72]

Short snip before I´m off:
Got it..
It´s the 5V supply..

[Martin72]

Hi,
A Multimeter is never enough for failure analyzis...
This I´ve learned over 20yrs ago in a "painful" way and it´s still valid.
Looking at the 5V for the Controlboard with scope, first setting the timebase to 10s because I wanted to see the signal rising.
But there´s no rising, there´s a huge noise on the dc-signal, reduce timebase to µs, aha...
Something is heavy oscillating and the signal remains even when you disconnect the plug from the controlboard, so it´s definetly on the supply board.
The board itself is "simple" as it can gets, several aux voltages from the transformer goes through rectifiers and then stabilizing with classical 78/79xx types, plus one 317.
And where every other voltage is clean, the 5V for the controller is oscillating.
So the 5V regulator must be replaced.
I got several ones here, but not in fully isolated housings.
Maybe for testing I´ll take one.
So or so, I think this was it...
If I´m right, next step will follow, what to do with the touch panel and (perhaps) with the backlight.

Martin
(edit why are the pics "shuffled"...it´s not my order I´ve placed them)