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    Laser Sensor and Counter

    Ah yeah, I remember, dodgy LEDs. Probably that's it then. Since your photodiode is transparent(?) the lead that does not contain the actual semiconductor should be the anode. I have found this to apply to dodgy LEDs even if they have non-standard leads. Let me know if you have found any LED or...
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    Laser Sensor and Counter

    Very surprised this did not blow up. The photodiode is forward biased with 5V - 0.8V across it. A massive current will flow in the base of the transistor. If it doesn't blow up it doesn't mean that it works or that it is a good design. So, you either try Hero's suggestions below and attempt to...
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    Laser Sensor and Counter

    Maybe a comparator circuit with a bit of hysteresis using a CdS cell or a photodiode? http://home.cogeco.ca/~rpaisley4/Comparators.html
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    Cross Reference for PCR 606J

    Or he fixed his lights and didnt say thank you.
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    precision photoemission assessment.

    Well I am sorry, but there will always be a degree of inaccuracy and your synthesis method will not be any better either. You can use statistical methods to further increase accuracy/precision. At your desired resolution and signal levels noise will be dominant which translates to highly...
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    Project Help / Advice

    I see. No that camera looks ideal since your board has a composite video signal input. I see from the schematics that, following the standard, a transceiver is used for the RS232 link, so you immediately need a similar IC on the side of your PIC, possibly the same (get samples from Maxim for...
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    Bubble memory cartridge for Sony/Tektronix Model 370 Curve Tracer

    I think I have seen that curve tracer in some dark and humid lab in the university of Manchester. Maybe I could look for it, they can use the newer ones I guess.  ;) How badly is this wanted?
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    precision photoemission assessment.

    That is painful. Maybe you could do this more indirectly. For example, you could look for an instrument that measures conductance G and since your material geometry will be known you could use this: σ = (G * length) / A    [sm-1] For example the Fluke 289 can measure down to 1nS (1G Ohm). Try...
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    Project Help / Advice

    Sure, you could pass digital signals down these lines. However you might have an issue with any DC-blocking capacitors in the audio signal paths on the DSK board. The other way would be to use an ADC/DAC and go analogue. I am sure there are other ingenious ways to use these ports for data, but...
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    Brightest LEDs on the planet?

    You could use a normal constant current source which will be quite inefficient, you could use a hysteretic driver much more efficient or you could use very specialised ICs based on hysteresis again like the new LT3743 or the MAX16818. These are in order of increased complexity. But I am sure...
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    precision photoemission assessment.

    Do you mean decimal points? That is a lot of precision... Have you looked for any "schientific" instruments for this purpose? What conductivity values/range do you expect? I dont recognise the term avalanche effect, what exactly do you mean? Maybe a process similar to avalanche breakdown in...
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    precision photoemission assessment.

    It is interesting how terms are misinterpreted across sciences. Anyway, so the photoelectic effect will change the conductivity of your compound, so you should be able to measure that with the electrodes. Is that what you are after? You mentioned 'circuit' in your first post?
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    precision photoemission assessment.

    I see...You could have the crystals/polymer deposited on an electrode and then form a near-uniform electric field by placing another electrode opposite to that and connect that to a high voltage source. The electrons freed will be accelerated to the anode. You can then put the assembly in a...
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    AC power outlet

    Wow. I hope no such "audiophile" falls in your hands :o I couldn't agree more, I mean who cares about the fifth harmonic which will be better filtered by the bypass capacitors anyway. One of the extremes I have seen (can't recall where, prob some advert) is a silver/rubber ring to put around...
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    AC power outlet

    Hero, by total nonsense are you referring to the fact that some people use batteries for their audio amplifier? From your post it looks like that.
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    AC power outlet

    I know some audio purists (also go by the name rich idiots by other people) use batteries to power their tube audio amplifiers. It is true that batteries will have lower noise than any other source. Adding a linear regulator will add more noise. Switching to batteries will be my last...
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    precision photoemission assessment.

    You really think I was asking for a definition? What I meant is, do you want to scan the polymer with a probe? Do you want a quantitative measure of current or some comparison method? What source of light source will you use? Do you have a vaccum chamber?
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    precision photoemission assessment.

    In what sense do you want to access the polymer?
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    Please recommend a Good Electronics Book

    Please tell us, What is your technical background What do you mean by power electronics What will the book be used for Regards, Alex
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    Cross Reference for PCR 606J

    I am surprised that they put an expensive (for Chinese product standards)  DIP package for the controller. Usually it's a COB.
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