Intel Coffee Lake PC Hardware


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April 27, 2018, 05:43:50 AM

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Intel Coffee Lake

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Offline Carl2 Topic starter
United States Posts: 1057
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  Another stage of amplification and the power stage can be turned on with a small amount of power.  Time to get back to the thermistors and see how that looks.  The final version will have the thermistor mounted on a copper plate or in the water, guess you want to set the temp and have lights for power on, power to Pletier and hopefully we can get a temp reading.
Carl2
Posted April 12, 2018, 12:35:06 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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I tried out the replacement thermostat yesterday, similar to what was in there earlier.  I get about a 4 V difference between room temp and under my tongue, again to much gain that has to be lowered and I'll have to do some level shifting to set the zero voltage.  It shouldn't be to long before I can set the desired temp and have the Peltier go to that temp.
  I cut some plexiglas but it didn't pass inspection so I have to do more cutting for enough good pieces.    Connecting the camera (tablet) to the computer will not allow access to the pics taken.
Carl2
Posted April 13, 2018, 12:39:23 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  Lots of thing to get done, looking through a box of resistors for the wanted value is a pain, it seems I spend so much time looking for this or that.  I still look through the Peltier vids hoping I'll find some new information that will be useful.  Things seem to be coming together and all the pieces will fit together nicely.
Carl2
Posted April 14, 2018, 12:41:01 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  While trying to adjust the gain of the amplifier I decided to get some info on the thermistor and play with some math. I had an idea the thermistor wasn't going to be all that linear but was surprised it was so far off.  There is circuitry that can make it more linear but I don't think it is worthwhile. In the end I compare one voltage with another to turn on and off the Peltier, both voltages between 0 and 12 volts. A nonlinear meter out put will give me an idea of the temp.
Carl2
Posted April 15, 2018, 16:17:02 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  I decided to play with some math to get the thermistor to give a more linear response,  The voltage source is plus and minus 12V, a series resistor is connected to the thermistor forming a voltage divider and the voltage across the thermistor drives the meter.  Lowering the series resistor improves the linearity according to the math. Today I'll try this and see how well it works.
Carl2
Posted April 16, 2018, 12:32:14 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  The circuit is getting moved to a printed circuit board, I haven't done this in ages and it takes a bit of time to get used to working with it.  I don't have enough resistors so I'm taking them from the bread board.  Guess it'll be done tomorrow or the next day.
Carl2
Posted April 16, 2018, 22:14:34 PM Logged

Offline DaveMorton
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I haven't breadboarded a project in over 20 years, so I can imagine the challenge. Kudos for getting fully into the DIY thing here, Carl. Cheesy thumbsup
Posted April 16, 2018, 23:38:14 PM Logged
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Offline Carl2 Topic starter
United States Posts: 1057
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  I've always enjoyed studding and working in electronics, I ran across half a dozen boards I've made while looking for parts.  I think the Peltier is a curiosity thing and will never make it in computer cooling because of cost.
I also feel there is a right way to do it that I haven't seen in any of the vids I watched.
Carl2
Posted April 17, 2018, 13:47:40 PM Logged

Offline Carl2 Topic starter
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  I believe I have everything on the printed circuit board, I'll go through it to be sure I have all the connections then apply power to be sure it works.
It also needs a comparator amplifier to turn on the power transistors to supply power to the Peltier.  It seems much smaller and compact now that it's on the PC board.
Carl2
Posted April 18, 2018, 11:58:41 AM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  Nothing done yesterday on coffee lake, spent a lot of time and money buying things needed that will be needed.  Made some rice pudding, came across an old computer mother board so I have another heat sink, fairly small maybe it can be used with a peltier.
Carl2
Posted April 19, 2018, 12:44:37 PM Logged

Offline Carl2 Topic starter
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  I got side tracked and had to do some repairs on something, poor computer needs work to be done on.  Maybe I can get a little done this evening.
Carl2
Posted April 19, 2018, 22:54:36 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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New day time to try to finish off the temp reader and get all the pieces to work as one.
Carl2
Posted April 20, 2018, 12:30:32 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
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  I found some connections not made and some connections made that had to be corrected.  The worst part was the connectors, these had to be taken apart and redone using a different method.  more to be done today.
Carl2
Posted April 21, 2018, 12:54:32 PM Logged

Offline Data
United Kingdom Administrator
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Carl, I haven't really commented on your work but I admire your dedication to this modification  Smiley 
Posted April 22, 2018, 12:49:08 PM Logged

Offline Carl2 Topic starter
United States Posts: 1057
Rank: Certified

I'm doing the circuit tracing now, I follow the thermistor output voltage through the buffer stage to the gain stage that would go to the meter.  the same voltage gets compared to a set temp voltage to turn off or on the power transistor powering the Peltier.  The Chinese have a few devices that measure temp and turn and off using a relay but the temp probe is very large and transistors can provide any current to the Peltier. 
Carl2
Posted April 22, 2018, 13:38:18 PM Logged
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