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OT: Need thermometer and light meter

OT: Need thermometer and light meter

(1) Need economical means to calibrate kitchen oven... wife complains that it's running hotter than setting. Oven has calibration tweaker, I just need to read real temperature and tweak it in.

(2) Inexpensive light meter to measure room lighting (comparing various LED formats).

Thanks! ...Jim Thompson

-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

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| 1962 | I love to cook with wine. Sometimes I even put it in the food.

Reply to
Jim Thompson
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An oven thermometer, relatively cheap.

CDS cell and measure resistance at x meters, or you could splurge and get the cheap extech LT300

Cheers

Reply to
Martin Riddle

Hey, Jim:-

I can send you one of each.. just paypal me the postage.

--sp

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Spehro Pefhany 
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Reply to
Spehro Pefhany

You probably already have a DMM that accepts thermocouple input, so all you need is the thermocouple.

Alternately, a cheap IR thermometer will work. But don't try to use it looking through the oven door window - it will measure the window, not the oven.

If for comparison purposes, anything reasonable from China will do. If absolute measurements are needed, a better instrument is needed.

Joe Gwinn

Reply to
Joe Gwinn

On Mon, 07 Sep 2015 15:11:40 -0700, Jim Thompson Gave us:

Jeez.. Harbor Freight Infra-red thermometer is $20 and is VERY friggin accurate.

Open oven door, and take a snapshot. Boom.... Job done.

Changing the calibration of it on the other hand is more difficult.

Easier to develop and use an offset sheet, like the NIST does when they certify a precision probe.

Reply to
DecadentLinuxUserNumeroUno

OK. Works for me. Thanks! ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
| E-mail Icon at http://www.analog-innovations.com |    1962     | 
              
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

How about some water in a pyrex dish. Adjust oven so water barely boils. Ought to be very close to 212 F. See what the oven dial reads.

Or use a tempil or Markel temperature indicating stick.

Dan

Reply to
dcaster

Easy. A Fluke 80TK thermocouple module (a bit pricey) or many inexpensive DVMs take a thermocouple input directly.

This will be a bit trickier. Percieved light levels depend a great deal on the wavelength distribution of the source. I have a digital light meter that has correction settings for Tungsten/Sun (2856 K), fluorescent, sodium and mecury sources. Unfortunately, it predates the upsurge in LED popularity.

There are also several different LED technologies in use (different phosphors, LED color mixes, etc) that may make metered values differ from perception if the proper correction isn't known.

If you have a good standalone photo light meter, that may suffice for purely comparative purposes.

--
Paul Hovnanian     mailto:Paul@Hovnanian.com 
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   -- Benjamin Franklin
Reply to
Paul Hovnanian P.E.

Keep in mind that the "dead band" for the built in thermostat can be many tens of degrees F. You need to let the oven cycle on and off at least a few times and read the high and low temperatures for each cycle before making adjustments. This seems to be a reasonable writeup of the process:

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Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.

Matt Roberds

Reply to
mroberds

Got a GE meter that i had been tying to sell on e-bay with no success. General Electric Exposure Meter Model 80W58Y4

Was asking $22,free shipping. Cherry condition, minor wear and tear. Give what you think is a reasonable offer, remembering that shipping can be expensive ($5-$10 range i guess) and address.

Reply to
Robert Baer

Thanks! ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
| E-mail Icon at http://www.analog-innovations.com |    1962     | 
              
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Infrared thermometer. $20 @ Harbor Freight.

There are no inexpensive light meters. There's one doohickey that connects to an iPhone that's under $100 bucks. Check BH Photo & Video.

--
Les Cargill
Reply to
Les Cargill

Cheap light meter: one of those solar "garden" lights. Disconnect the solar cell from the garden light circuit, and connect a voltmeter to the cell. Not calibrated, but good for comparison. I'll send you one if you want.

Ed

Reply to
ehsjr

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