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    How to transmit music from PC to music system wirelessly...??

    I read somewhere on a FCC page that the legal limit (88-108) in the US is something ridiculously like 15nW?? Enough to transmit 10'
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    How to transmit music from PC to music system wirelessly...??

    The RF power direct out from the BH1417 is low typically about 100dBuV or about -7dBm (0.2mW). The output impedance is 75Ohm and not 50Ohm as one will expect with most RF systems.
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    Doubling 7805 regulator current is effective?

    They could have been from the same batch but I can't remember. I have also seen a frequency standard product that one company sold many of, that paralleled 3 or 4 of these regulators because of space problems. I own one and it's working for the last 5 years without failure. Can't say if they...
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    Doubling 7805 regulator current is effective?

    I know there are many arguments about this issue of paralleling regulators. Looking at the internal structure of the LM7805 it looks possible to do this.  Some time ago I experimented with true national 7805's and found that they do indeed share current when run near or at their maximum current...
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    motorola TO3 puzzle

    Plant number Batch number
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    Turn on after 3 seconds turn off

    The protection can activate with or without speakers connected. I this case my money will be on the protection circuit doing strange things.
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    T.V ( No display )

    In most cases no picture means lack of high voltage to the CRT (picture tube). It is strange that you can still hear sound because in general the auxiliary windings on the EHT transformer power some of these circuits. Make sure there is high voltage to the tube by placing your hand on the tube...
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    Turn on after 3 seconds turn off

    Protection is activated when the sense circuitry determine a dangerous DC offset that may damage the speaker. The sense circuitry itself could be faulty and activate the protection relay. If you have a diagram you can make measurements to see what is going on.
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    Service Manuals

    Most older HP/Agilent manuals in your test equipment section can be downloaded free from Agilent's website. http://www.home.agilent.com/agilent/facet.jspx?t=80101.k.3&co=152502.i.1&cc=US&lc=eng&sm=g
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    Oscillators

    http://www.electronics-tutorials.com/oscillators/oscillator-basics.htm http://web.telia.com/~u85920178/blocks/osc7m00.htm
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    Anti-Static Wrist Straps - use with battery powered cct's ??

    I hardly ever use wrist bands. The few occations where I used one I just clamped it to cct ground. Some people like to work on a anti-static mat which is just a very high impedance to earth. How did your LDR circuit turned out?
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    Comments welcome re. amplification/scaling and offset/bias CCT

    If you don't know what to do with the spare amp put it at the top as another buffer by breaking at the blue line. Circuits can quicly get out of hand and you end up with 10 opamps! ;D
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    Comments welcome re. amplification/scaling and offset/bias CCT

    You could also try this clamp idea. It will require 1 extra opamp. This will prevent your offset value from going higher than your LDR value and will then prevent the opamp going negative. As long as the offset is lower than the LDR value it will have no effect on the circuit. Just a idea. If...
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    Remote control - all i need is one bit (;

    look here http://www.radiometrix.co.uk/index.htm They have agents many places. In the US it is sold by Mouser and the cheap ones is about $10
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    Comments welcome re. amplification/scaling and offset/bias CCT

    You can try this. Play with the RxC constant to reduce flicker response. Last variation will allow you to use smaller C value
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    Comments welcome re. amplification/scaling and offset/bias CCT

    This what I mean. Also I would add a buffer to prevent any loading by the B2 on the LDR when B2 goes low resistance which will place R6 in parallel with R10.
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    Comments welcome re. amplification/scaling and offset/bias CCT

    Your diagram does not indicate how the sliders are connected. As it is drawn it does nothing when you vary the pot. Indicate the direction that slider B1 will move in respect to B2 when adjusted. This is all important. Maybe fix the drawing to avoid confusion.
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    Comments welcome re. amplification/scaling and offset/bias CCT

    Dual gang pots are normally made for audio and will likely be log not linear. This could be why you see the rapid increase at the end. I think if you look at the pot markings there is a B for linear or A for audio or log. more here http://sound.westhost.com/pots.htm#using
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    dBm to Vrms

    Your scope will give 2 X the reading because it is not terminated into 50 Ohm Your scope will also read lower because the 210 has a 60MHz BW meaning that the reading at 60 MHz will be up to 3dB lower. A scope of >= 100Mhz will give a more accurate reading.
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    Help! I have a Really Weird Part

    It is called a Shockley Diode http://www.allaboutcircuits.com/vol_3/chpt_7/3.html 2 of these in anti-parallel used to make a diac
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