Classic KISS electronic displays

[Reeve]

I recently bought Classi KISS No 018....... After being sat around for a few weeks due to work and xmas etc I started to run through the unit.

As suspected when I purchased the unit the electronics are not quite right. The person I'd bought it off hadn't used the unit for some two years and had a friend service it.

He fitted new cells, batteries and he changed the lascar displays too try and correct the problem. I guess unknown to him the replacement DPM1AS-BL have a different circuitry arrangement. The main changes looking at the circuit diagram seems to be the in-built capacitor the shuffling of pins and the back light.

I'm sure others here have encountered this problem, so I'm looking for advice. Can I get the older "not manufactured" displays anywhere, change the circuit board, change the electronics or just make up my own PCB's....

Only 1 of the original lascar displays was supplied along with other spares, but this seems to also give erroneous, wandering, non-calibrating values. Assuming the damage was caused by condensation (no obvious salt water marks) would it normally be the PCB or the display that's knackered? Does acetone help clean up the board.

Would rather try and repair/ replace display/ PCB or some other cheaper option at this stage as there are some other things that need to be sorted before I can use this unit.


Many Thanks
Gareth

p.s tried the archives but couldn't find the answer

[Muddweller]

Hi Gareth,

Firstly I can't draw on personal experience with KISS electronics, but I like many others on here made my own.

Could you be a bit more specific regards the prob, how much variation over how long a time period ?
Is the problem on all three displays ?
Have you measured the output of the cells with a suitable load and are they stable?

I'd be tempted to remove the cells and introduce a fixed reference voltage from a potential divider network (use a vairable resistor to drop a source such as 1.5 AA battery) of around 15mv to all three displays and see if they wonder with that. When electronic components become faulty they can sometimes become sensitive to temperature, try warming them with a hair drier and cooling them with some aerosol freezer (or depressurised air from your tank if you haven't got any of that) there should not be any significant change. If there is you can use this technique to narrow the area down to the faulty component.

If a PCB has been exposed to fresh water for any significant time, evidence in the form of white furring around component legs and dulling/corrosion of the solder pads can usually be seen, obviously with salt water it becomes blatently obvious and under no circumstance would I attempt a repair since no matter how well you clean it the board may become conductive over time.

Hope you sort it.

Karl

[Reeve]

I've found a problem, with the electronics. Any thoughts appreciated. I've trawled the archives and not found the answer i want, but am definetaly, more informed.

The person I bought my KISS off, having not used it for 2years or so couldn't get the electronics to work, even after servicing it with a friend. What they did was first replace cells & batteries. Then they went to Lascar and bought the DPM1AS/BL and fitted these.

At this point they gave up and sold it to me. Having spoken to Lascar, I find that the DPM1 (old displays) are incompatable along with the fact that they had an extra resistor installed to the DPM. So I'm at a quandry as to what to do for the best.....

1. Try and aquire some old DPM1 and piggy back the required resistor - this assumed the board is still ok, they currently work just not getting the right readings, well someone in the region of .12 in air.
2. Purchase new MOD2 backlit board, assuming the backlit displays can drop straight in and they're sold like this.
3. Purchase the backlit electronics complete.
4. Purchase the new one piece electronics.......... Do you need a new kidney or does it just drop straight in?


It would be good if I could find someone with an older classic KISS so I could try and drop their DPM1 display in to see if my boards are still ok.


Gareth

[aquaholic]

Hi Gareth,
Not great on electronics myself, but do have a Classic KISS.. Zak might be the one to comment...
You can download a copy of the new manual here: http://www.jetsam.ca/
1. Looks to me like the boards are reading non-adjusted output from the O2 cells?? Maybe the new baords don't have the correct potentiometer setting?
Have you checked the O2 cell output?
Should be around 11-12 mV (0.12V) if healthy, under 9mv is not healthy.
2. Depends on which version of the 'old' meters you have (this is from memory, so may be totally wrong) :
Version 1 black delrin housing, not backlit and used a 12V battery, O2 calibration via removable 'MP' type reg plug on the back
Version 2 as above, but with backlit displays using a shorter 6V battery
Version 3 have a polycarbonate housing, backlight display, 6V battery, turn switch calibration points.
Version 1 & 2 are the same size housing, but beware of the different power requirements for the older boards,
so 3. is an option.
4. the new electronics come complete with their own kidney.
Hope this helps a little.
Anke

Originally Posted by Reeve

1. Try and aquire some old DPM1 and piggy back the required resistor - this assumed the board is still ok, they currently work just not getting the right readings, well someone in the region of .12 in air.
2. Purchase new MOD2 backlit board, assuming the backlit displays can drop straight in and they're sold like this.
3. Purchase the backlit electronics complete.
4. Purchase the new one piece electronics.......... Do you need a new kidney or does it just drop straight in?
It would be good if I could find someone with an older classic KISS so I could try and drop their DPM1 display in to see if my boards are still ok.
Gareth

[wreckweasel]

Originally Posted by aquaholic

Zak might be the one to comment...

Nah, its been dealt with extensively on RBW, so I'd rather not add to the noise.

[aquaholic]

Originally Posted by wreckweasel

Nah, its been dealt with extensively on RBW, so I'd rather not add to the noise.

Fair do.. haven't been following all the pages all the time... too busy varnishing shelves at the moment

M u s t n o t k i t f e t t l e!!! Must not... not...