[time-nuts] Tbolt temperature Control

[Don Latham]

Heck, Warren, I'll put it on the line :-). Use a very simple and cheap
processor such as a Picaxe, pass the rs232 through it to Lady Heather etc,
and capture  the temperature, using it appropriately. Should work nicely
and keeps the temp control local. Even put a little LED on it to indicate
state.
Don

WarrenS
> TBolt Nuts
>
> To keep My TBolt's temperature constant so that the environment has
> minimal effect on it,
> I use an aquarium temperature controller (modified to have low hysteresis)
> connected to a low wattage light bulb, placed in a box with the TBolt.
> It works OK and keeps the TBolt's temperature constant to well under 1
> deg.
> To do it better and make it  more hi tech,
> I'd like to have the temperature control based on the TBolt's internal
> sensor.
>
> What I have found works well is to use the TBolt's own RS232 temperature
> sensor output data,
> and with a modified PID type of S/W controller, turn an external heater
> &/or cooler on off.
>
> The heater can be an appropriate power resistor or transistor dissipating
> up to about 4 Watt,
> mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is
> a small fan blowing
> at a heatsink mounted on the top of the TBolt's case.
> Turning the fan on & off with a S/W driven switch, can be used to keep the
> TBolt's
> internal temperature very constant over a limited external temperature
> range.
> A standard PC chip fan & heatsink may be OK, if it does not add Phase
> noise due to it's vibration.
>
> Because of the long time constant and slow response of the internal
> temperature sensor,
> a single digital on-off bit, updated at a max rate of once per second
> works great for control,
> No analog needed. To keep the hardware and interface circuit simple,
> I'd like to be able to use one of the unused standard RS232 outputs,
> such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
> This is no problem when doing this in a DOS program or from an added
> microprocessor
> that monitors the Tbolt's  communications,  But the question is,
> can it be done in Windows in such a way that a modified existing program
> such as
> Lady Heather or Tbolt monitor could control an already existing readily
> available digital bit?
>
> Being a control person, Doing a software algorithm is the easy part.
> Making Windows do any kind of non standard I/O control, is way above my
> capability.
> I'd like to get feedback from a Windows expert if there is a simple way to
> control an existing Digital bit
> that would be available on a PC being used in a typical setup that is used
> to monitor the Tbolt.
> One way I have heard suggested is to use the sound card output,
> but I'd like to keep it even simpler than that, Any suggestions?
>
> If anyone is interested in developing a program to make an existing stand
> alone micro
> or basic stamp to include this function they can contact me off line for
> some sugestions.
>
> Thanks,
> ws
> ******************
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>


-- 
Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com