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Products => Test Equipment => Topic started by: TheEPROM9 on May 07, 2013, 07:12:02 pm

Title: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on May 07, 2013, 07:12:02 pm
This little beauty was found in the engineering departments WEEE bin, that bin supply's so many nice things =-)

The company Comark are still going but sadly there is no information what so ever on this thermometer, I believe it is thermocouple as whats left of the wires seems to work but it is out of cal quite badly, there may also be other problems. Any user or service manuals would be fantastic and allow for such calibrating.

I will have to past the pictures separately due to file size.
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on May 07, 2013, 07:13:43 pm
More Pics
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on May 07, 2013, 07:14:44 pm
The rest of the pics =-)
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: SeanB on May 08, 2013, 04:14:52 pm
Nice type K multiple input indicator. Probably all that it needs is a short of copper wire across each input, a clean up of the contacts on the switch at the rear and then checking that all channels display the same temp, which should be room temperature +-5C. If so then nothing needs doing really.
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on May 09, 2013, 03:30:17 pm
You are right, after being in a skip it could do with some maintenance. I do need to find it a proper probe and find the cal pots,then it should be happy.
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TerminalJack505 on May 09, 2013, 03:50:14 pm
With all that circuitry I kind of expected something more than just "027".

Maybe "027.123".  Or, perhaps, "Sorry, Dave.  I can't let you do that."
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on May 09, 2013, 05:00:07 pm
With all that circuitry I kind of expected something more than just "027".

Maybe "027.123".  Or, perhaps, "Sorry, Dave.  I can't let you do that."

It is an excellent example of integration in technology.

Hell my old laptop made in 2006 is less powerful than the most powerful mobile phones. Remarkable development if you ask me.
However the old stuff just had the cool that the modern stuff does not.
Title: Re: Comark Digital Thermometer 5000 (1970s thermometer)
Post by: TheEPROM9 on July 08, 2013, 08:24:06 pm
Nice type K multiple input indicator. Probably all that it needs is a short of copper wire across each input, a clean up of the contacts on the switch at the rear and then checking that all channels display the same temp, which should be room temperature +-5C. If so then nothing needs doing really.

Indeed you seem to have been correct, used contact cleaner on all the connectors and pots, seems to be much more stable saying 23*C. Doing a long running test =-)