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  1. kellys_eye

    Any help on id of this semiconductor?

    Practically any generic low power PNP germanium will probably work although, depending on the circuit, it might be simpler to redesign that particular part to use a silicon transistor. GO to Digikey (or similar) and do a parametric search for 'transistor, PNP, Germanium, AF etc and see what...
  2. kellys_eye

    Twinax/Triax Schematic Symbology

    If a symbol doesn't exist then devise one! I found this on my first Google though:
  3. kellys_eye

    ebike with speaker amp as a watt amperage is it possible

    If you want to run a 12V amplifier from a 36V battery then get a converter (buck converter) to reduce the 36V to 12V. But funny how you can put a . in your user name but not in your sentences.....
  4. kellys_eye

    Any help on id of this semiconductor?

    Looks like 2N170... to me as well. Could be 2NI70... though. (I'm being sarky..... all I see is the WORD 2N170. No picture)
  5. kellys_eye

    Twinax/Triax Schematic Symbology

    Quite an unusual connector! But not the 'BNC' the OP spoke about...... My only experience of triax was during the install of marine HF transceivers where the triax was connected in the transmitter, right on the main PCB using double clamps. I don't doubt the full double-screening is utilised...
  6. kellys_eye

    ebike with speaker amp as a watt amperage is it possible

    Eh? The power output of the amp will be according to its actual specification. Buy/use a 25W amp and it will put out 25 watts. Total power drawn from the battery will be the wattage of the motor, controller and amplifier. Where you'd mount 3000W of speakers is something I'd like to SEE!
  7. kellys_eye

    6 Sided RGB LED Alternating Moodlight

    Nope - you'd need a PWM (pulse signal) of 50% duty cycle (where 100% represents 'full on') that falls to 0% over the set time period. Regulating LED brightness by resistor is a 'fools errand'.
  8. kellys_eye

    Remote control circuit of old TV?

    All my sources have been depleted - the only information I got was as per the previous posts. You might find some more specific responses on a dedicated TV repair site.
  9. kellys_eye

    Twinax/Triax Schematic Symbology

    They're not. AFAIAA the tri-axial end terminates at a screw terminal/clamp arrangement and the BNC ends are made up as standard i.e. the second screen at the BNC end is unconnected therefore not shown on the designation.
  10. kellys_eye

    EG&G PAR 5210 Lock-in amplifier repair

    I wouldn't be at all surprised to see the almost exact same fault with this one as the other! I wonder if capacitor (tantalum) manufacturers did a MTBF test on their parts and, if so, ever published the results!
  11. kellys_eye

    EG&G PAR 5210 Lock-in amplifier repair

    Michelle Obama?
  12. kellys_eye

    6 Sided RGB LED Alternating Moodlight

    In order to fade, you will need a variable PWM signal and another signal to control the rate at which the 'fade' happens. Then triple it (one each for R, G and B) and apply it to appropriate drivers. Add a circuit to randomise the effect and there you go! Another way to look at it would be to...
  13. kellys_eye

    Remote control circuit of old TV?

    I know the IR module is missing but the IR module must connect to some other circuit boards in order to interface with the various functions the remote control offers i.e. volume, channel change, brilliance etc...... Without 'knowing' the set I can't even say WHAT functions the IR remote...
  14. kellys_eye

    Siemens Thyristor SPNO 3RF23101AA02 shorted

    Seems a bit 'low'..... either way, the module is good for 10A (2.5kW) but devices do fail occasionally. Simple one-for-one replacement is required. Don't buy it direct from China though........
  15. kellys_eye

    Secret Mission Motion Sensor

    The simplest form would be to use pressure mats! Next would be the IR sensing modules that are common with burglar alarms (adjustable sensitivity - stops pets activating it). Either way, all you get is a simple 'closing contact' that can activate whatever it is you want to do - start a webcam...
  16. kellys_eye

    Help! Color dropping in and out on 1978 Zenith Chromacolor II television

    Google 'NTSC color burst signal'
  17. kellys_eye

    Tektronix TDS3054 data acquisition failure

    I think you might be looking at more than one fault - or, more likely - a fault that links the same clock frequency of the display to the sampling circuitry.
  18. kellys_eye

    Tektronix TDS3054 data acquisition failure

    I was intrigued by your first picture that shows a red 'spike' outside the trace area and indicative of a video issue.
  19. kellys_eye

    Remote control circuit of old TV?

    We're getting no where..... 1. Remount the tuner module where it belongs 2. Compare it's position with your drawing showing the component locations: 3. Try to identify where the remote control receiver module SHOULD HAVE BEEN. 4. Where does the other end of this three-pin connector...
  20. kellys_eye

    Remote control circuit of old TV?

    There are no IC's on any of those boards that correspond to remote control circuitry.
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