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Thread: Where I will get original crystals in Lamington Road

  1. #1
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    Default Where I will get original crystals in Lamington Road

    Most of the crystals available in Lamington Road is duplicate chinees make. Any one knows the source from where I will get original crystal.
    Or source in Pune.

  2. #2
    Super Moderator T-1000 docel's Avatar
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    So whats wrong with the chinese xtls?
    They are OK, unless you have some tight tolerances.

    Or
    you can place a custom order with your specifications ( at several tens of the Chinese cost and a lot of time) from http://andhraelec.com/ They are quite good.

    Also KELTRON used to make them .....
    http://www.keltroncomp.com/kxl/index.html
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  3. #3
    Senior Member Cyborg
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    Default it does'nt matter

    don't forget the crstal which you are saying are dupicate are the original product of the cmpany where it is manufactured.

    so it does not matter dupicae or original what matters is Acuuray ,& the most important RELIABILITY.

    Many of us are purchasing crystals frm laminton road hey and all of them have both of this


    regards

    ulhas

  4. #4
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    Default Duplicate Crystal

    Most of the crystals which are available in LR is KDS`s duplicate. Last time we have purchased same crystals of 4MHz and we tested the xtal using frequency counter and we found the frequency like 3.9MHz to 4.2MHz. There for we stop using those duplicate.

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    What kind of application are you in, and what tolerance do you need??

    I would also like to know how you tested the frequency of the crystal..

    just curious...
    .... I didnt do it ! ....

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    Super Moderator T-1000 docel's Avatar
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    Right Jobin!
    I wanted to ask this same question but thought better of it.

    It is just +/- 150Kc tolerance.........What do you expect ? for less than 10 bucks???

    Besides, the load capacitances should be according to the Manufacturers datasheet. If unknown, then one of the two load caps can be made variable and the Crystal "pulled" to the desired freq. This is called 'netting' and is necessary even for 50ppm xtals.

    I have pulled 50kcs out of a 50ppm crystal @ 8Mhz for my VFOs. ( they cost me around 250INR+taxes+post) whereas the cheap "duplicates" could be pulled to 250kcs (@3INR bulk).

    Even TCXOs can be pulled...... :!:

    A badly designed oscillator WILL pull the Xtal freq. due to stray capacitance, wrong loading and phase-shift. And if you did a "breadboard".... :roll:
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

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    Default Projects are commercial

    Projects are commercial and we can not use trimmer or any other capacitor for pulling the frequency. We are using 4MHz xtal for PIC microcontroller and faced this problem.
    I know we can pull the frequency of xtal. I did these in experiment for crystal based oscillator for Tx/Rx application.

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    We are using 4MHz xtal for PIC microcontroller and faced this problem.
    Is it a time critical application?? Even though I might be deviating from the original topic, which was as to the availability and which I know nothing about, I would like to know the kind of applications that requires such tolerance, especially with a PIC. I guess UART or IIC or SPI will be happy with your tolerance..
    .... I didnt do it ! ....

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    Senior Member T-1000 debu's Avatar
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    Default

    For medical, aerospace or "Strict" real-time industrial applications, I prefer to use MAX038. Maybe it is what you require. For everything else I use local XTals. I once picked up a box of 1000 peices of XTals (Totally mixed, every size, shape, frequency), that box still serves me, its still half full :wink: and I never bought an XTal since.
    I think we can all learn to improve our circuits, and reduce the impedence and noise. You can never get rid of it, but improve it a little, one PCB at a time. No need to blame it on the XTals.

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    Super Moderator T-1000 docel's Avatar
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    Are you using the Capacitors??
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

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