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CdS Photoresistors (5-Pack)

Model:

276-1657

 | Catalog #: 276-1657
Price:
$3.99
$3.99
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Product Summary

Your stop for a variety of diodes and resistors.

Looking for photoresistors? We have a selection for you. CdS photoresistors respond to light. Various styles and ratings.

Pricing and availability: Please note that all prices are subject to change without prior notice. Prices advertised on this site are for online orders only. Prices on some items may differ from those advertised in RadioShack stores. All merchandise may not be available at all stores, and all stores may not participate in all sales promotions. We recommend you contact the store to confirm product availability and price.

What's in the box

  • 5 x Cadmium Sulphide (CdS) photo cells - various styles and values
 

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Usually ships in 1 - 2 business days

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Other ways to get it


In store: Check availability
By phone: 1-800-843-7422

Manufacturer Warranty

  • Parts: 90 days
  • Labor: 90 days
Tech Specs

Customer Reviews

REVIEW SNAPSHOT®

by PowerReviews
RadioShackCdS Photoresistors (5-Pack)
 
3.3

(based on 30 reviews)

Ratings Distribution

  • 5 Stars

     

    (11)

  • 4 Stars

     

    (4)

  • 3 Stars

     

    (4)

  • 2 Stars

     

    (4)

  • 1 Stars

     

    (7)

63%

of respondents would recommend this to a friend.

Pros

  • Reliable (11)
  • Versatile (9)
  • Good length (6)
  • Good value (3)

Cons

    Best Uses

        • Reviewer Profile:
        • Casual user (9), Enthusiast (7), Power user (5)
        • Primary use:
        • Personal (19), Business (5)
        • Was this a gift?:
        • No (11)

      Reviewed by 30 customers

      Sort by

      Displaying reviews 1-10

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      (3 of 4 customers found this review helpful)

       
      5.0

      They work fine, for me at least

      By TL

      from North Jersey

      Verified Reviewer

      Pros

      • Versatile

      Cons

        Best Uses

        • High-End Equipment

        Comments about RadioShack CdS Photoresistors (5-Pack):

        I needed a photoresistor with a fairly low dark resistance to activate a relay via an NPN transistor. Of the 5 in the package, the tiny one has the highest resistance and the largest ones have the lowest resistance, with one of them being significantly lower than the other. For those taking issue with the lack of a datasheet - take your own readings with a multimeter if you need to know exactly how many ohms they are at a given light level. Even if you buy a pack of what is claimed to be 5 of the same component, no two photocells are going to have the exact same characteristics so a data sheet won't do you much good. All that's certain is that they go over 25 megaohms in complete darkness. When I introduce the slightest amount of light, the tiny one went to around 1.2m and the big one went to around 150k, well under the 270k max that I need to drive the relay. The others went to 200-300k. There's enough variance in this assortment that at least one of them should work for your project.

        Not sure why on earth Radioshack classifies these under diodes and rectifiers though; clearly they're nothing of the sort.

        • Primary use:
        • Business
        • Was this a gift?:
        • No

        (1 of 1 customers found this review helpful)

         
        5.0

        How to use

        By Amos

        from Knoxville, TN

        About Me Enthusiast

        Verified Reviewer

        Pros

        • Long Life

        Cons

          Best Uses

          • Determine A Light Value

          Comments about RadioShack CdS Photoresistors (5-Pack):

          Cds cells are used as one half of a voltage divider between voltage source and ground, the other half being a resistor of about 10K. The output is taken between the Cds and resistor and is usually used to drive a transistor or relay load. Use a search engine for photo cell as voltage divider for details.

          • Primary use:
          • Personal
          • Was this a gift?:
          • No

          (18 of 18 customers found this review helpful)

           
          3.0

          Here's the datasheet

          By JakeA

          from SCV, CA

          About Me Casual User

          Verified Reviewer

          Pros

            Cons

              Best Uses

                Comments about RadioShack CdS Photoresistors (5-Pack):

                A little google searching and I found the specs:

                http://support.radioshack.com/support_supplies/doc38/38703.htm

                Photocells Multi-pack (5)
                (276-1657) Specifications Faxback Doc. # 38703

                TYPE ILLUMINATION @ RESISTANCE ILLUMINATION @ RESISTANCE

                P722-7R: ......... 1 Lux .....@.. 13 kOhms ..... 100 Lux ....@... 900 kOhms
                P722-5R: ......... 1 Lux .....@.. 15 kOhms ..... 100 Lux ....@... 1.1 kOhms
                P1201: ........... 1 Lux .....@. 120 kOhms ..... 100 Lux ....@..... 7 kOhms
                P201D-7R: ........ 1 Lux .....@. 130 kOhms ..... 100 Lux ....@..... 8 kOhms
                P201D-5R: ........ 1 Lux .....@. 160 kOhms ..... 100 Lux ....@..... 9 kOhms

                CELL RESISTANCE
                POWER VOLT.BETWEEN 10 LX RESPONSE TIME
                TYPE DISSIPATION TERMINALS 0 LX MIN~MAX RISE DECAY
                P722-7R: .. 150 mW ... 200 VDC . 0.5 MOhms . 2.5~7.5 kOhms .. 50 ms . 40 ms
                P722-5R: ... 70 mW ... 100 VDC . 0.5 MOhms . 5.3~15 kOhms ... 50 ms . 40 ms
                P1201: ..... 70 mW ... 100 VDC ... 5 MOhms .. 20~60 kOhms ... 40 ms . 30 ms
                P201D-7R: . 100 mW ... 200 VDC .. 20 MOhms .. 23~67 kOhms ... 50 ms . 20 ms
                P201D-5R: .. 50 mW ... 100 VDC .. 20 MOhms .. 48~140 kOhms .. 50 ms . 20 ms

                • Primary use:
                • Personal

                (3 of 3 customers found this review helpful)

                 
                5.0

                Good product in local stores is a plus

                By El Berto

                from Reno

                About Me Enthusiast

                Verified Reviewer

                Pros

                • Consistent Performance

                Cons

                • Poor documentation

                Best Uses

                • Small Signal Project

                Comments about RadioShack CdS Photoresistors (5-Pack):

                Despite the lack specs, these LDRs are very good for the price. And they are right down the street. I have used many and find them to be quite reliable when used PROPERLY. Treat them as you would treat a 1/8 watt resistor and you will have no problems. No loads in series. Use these to drive a transistor that drives the load.

                • Primary use:
                • Personal
                • Was this a gift?:
                • No

                (3 of 3 customers found this review helpful)

                 
                5.0

                TWILIGHT SENTINAL

                By ILL WILL RECORDS

                from LOS ANGELES, CA

                About Me Enthusiast

                Pros

                • Good Length

                Cons

                • No Performance Increase

                Best Uses

                • Travel

                Comments about RadioShack CdS Photoresistors (5-Pack):

                This iTem is a fix formthe auto night lights or twilight sentinal on your automobile. I used it and now the system works just fine (92 CAD SEV 4.9)

                • Primary use:
                • Personal
                • Was this a gift?:
                • No

                (2 of 6 customers found this review helpful)

                 
                1.0

                Saturate when voltage is applied

                By EE

                from Providence, RI

                About Me Power User

                Pros

                • Inexpensive

                Cons

                • Poor Quality

                Best Uses

                • Landfill Material

                Comments about RadioShack CdS Photoresistors (5-Pack):

                The part works on the bench with a DMM. In circut under real voltage 5-12V the part saturates and the resistance drops regardless of the light intensity.

                • Primary use:
                • Personal
                • Was this a gift?:
                • No

                (1 of 3 customers found this review helpful)

                 
                3.0

                Don't Last Long

                By skeeter_mcbee

                from Vancouver, WA

                About Me Casual User

                Verified Reviewer

                Pros

                • Versatile

                Cons

                • Wears Easily

                Best Uses

                  Comments about RadioShack CdS Photoresistors (5-Pack):

                  I use my photoresistors in my breadboard to just play with my Arduino, and it seems to me like these things don't last too long. I bought mine in April, and in June, they all seem to have stopped working. It could just be my fault for constantly taking them in and out, but hey, I hack IRL. I only use these for prototyping. My advice? Don't keep buying them unless you plan on going to the store every few months. And for me, when I don't have a car, sucks.

                  • Primary use:
                  • Personal
                  • Was this a gift?:
                  • No

                  (1 of 5 customers found this review helpful)

                   
                  1.0

                  No Good

                  By Crazy J.

                  from Lewisburg, TN

                  About Me Enthusiast

                  Verified Reviewer

                  Pros

                    Cons

                      Best Uses

                        Comments about RadioShack CdS Photoresistors (5-Pack):

                        Bought the 5 pack. Brought the home and begin checking them (a must when buying parts from radioshack) none of them worked. A bad batch I guess, not really sure, just know I'm out the $4 plus now gotta spend even more gas to drive back and return for another batch that may or may not work.

                        • Primary use:
                        • Personal
                        • Was this a gift?:
                        • No

                        (6 of 10 customers found this review helpful)

                         
                        2.0

                        Random assortment

                        By Bruce

                        from Baltimore, Md

                        About Me Casual User

                        Pros

                        • Good value

                        Cons

                          Best Uses

                            Comments about RadioShack CdS Photoresistors (5-Pack):

                            I was looking for a photoresistor for a light-sensitive switch. The price is good for five LDRs. However, the five are in random sizes and values from tiny ones that are still about 100k ohms when illuminated to medium ones that are about 20k ohms. Not knowing what specification I was getting meant more time for trial-and-error and needing more components on hand to use with the LDR.

                            (0 of 4 customers found this review helpful)

                             
                            3.0

                            CdS Photoresistors (5-Pack)

                            By Y Bridge Kid

                            from Zanesville OH

                            About Me Casual User

                            Verified Reviewer

                            Pros

                              Cons

                                Best Uses

                                  Comments about RadioShack CdS Photoresistors (5-Pack):

                                  Purchased this pack to repair outdoor solar lights. The small ones worked fine but for some reason the large ones did not. (probably not right resistance range?) It would be nice to be able to purchase only the size I need.

                                  • Primary use:
                                  • Personal
                                  • Was this a gift?:
                                  • No

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