Search results

  1. elebish

    Yamaha integrated receiver SR-300 subwoofer not working

    Check speaker with one lead disconnected. Should read 4, 8, or 16 ohms if good. Also check all voltages at IC 303 and touch surface of IC with unit powered up to see if it is cold or hot. Cold would mean an open and hot above 150f would indicate a possible short. Replacing IC303 would require...
  2. elebish

    I have a celestial 5188I rear projection tv and it keeps switching off at random .

    You wouldn't have some stray "rf" signals going through the area that turns off the set like a remote control, would you? That, of course, depends on the type of remote you are using. Back in the 50's, I had a customer with a Zenith that was randomly changing channels and shutting off. Turned...
  3. elebish

    Refrigerator Not cooling

    Most refrigs use a thermistor near the compressor that heats up under current flow to the compressor and changes resistance. This thermistor looks like a thick disc that is very fragile and breaks easily and is generally inside a cover or housing. It's made of carbon and fits between 2 spring...
  4. elebish

    Dishwasher PCB resistor burned out

    Try www.wiringdiagrammanual.com or www.manualuniverse.com. You may also try getting the part number of the pc board and google it. You may have to replace the board because burned boards leave carbon traces that conduct.
  5. elebish

    need help identifing this diode,radar unit

    Some diodes used in high frequency devices are very sensitive and can be blown with an ohmmeter during checking. Ed.
  6. elebish

    Can I use a resistor as a fuse?

    What may measure 'zero' ohms may not be true zero. Use a 5 1/2 digit 4 lead ohmmeter and check again. Maybe we can call them fuse-able wires. The type of metal these are made from could be part of the answer. Ed.
  7. elebish

    Finally got me a 'scope - Have some questions

    One should use a non-metallic screwdriver when adjusting trimmer caps in any electronic device. Also, when waveform distortion is present on an o'scope, turn off fluorescent lights in the area and check waveform again.
  8. elebish

    compressor motor

    Sounds like a bad start capacitor or a bad winding in the motor. Ed.
  9. elebish

    Repair of HM1005 oscilloscope

    You should have removed the case and powered up the scope and wiggled each component in the suspected circuit to see if there might have been a loose connection or bad solder joint. Sometimes using a heat gun on suspect areas of the circuit may show a problem if the problem only shows after...
  10. elebish

    Capacitor replacement for pedestal fan

    There are different types of electrolytic capacitors. Most are used for filtering (passing) small amounts of ac but blocking larger amounts of dc. The types used for motors are actually used to balance out the reactance of the inductive capacitance of the motor windings. The trick is to make the...
  11. elebish

    capacitor help

    The fact that 1800 uf is used instead of the common value of 2200, could be because 1800 is what the design engineer intended to be used. It all depends on the circuit involved. I would stick to the original value unless I had no choice. Don't second guess the design engineer unless you...
  12. elebish

    Please Help? Vacuum Tube TV

    Glad to see the tv working! Ed.
  13. elebish

    Iwatsu SS-5711

    I'm pretty sure those 2 caps were your problem as they were my problem. Do not over adjust the intensity pot on the Z axis board. Ed.
  14. elebish

    VDC leakage in bass amp?

    Which jacks are you referring too? The speaker jacks may have 'floating' grounds due to the design of the complimentary audio power outputs. They are generally plastic jacks. The low impedance signal (1/4 inch) input sleeves are normally chassis grounded and the HI impedance XLR inputs have a...
  15. elebish

    Burnt Pin On 11 Pin Relay-Need Major Help

    "Transformers only work when ac or pulsating dc is applied!" Whatever load is being drawn through the relay contacts that is getting the pin burned, is your problem or the supply voltage is too high. Ed.
  16. elebish

    No Color. Black and White Picture

    You need an oscilloscope. Check the composite (NTSC) video signal and it will tell you all you need to know. The 3.58 Mhz color oscillator is synced by the broadcast signal and is actually 3.579545 Mhz and must be on the back porch of the horizontal blanking pulse to get color. Do NOT adjust...
  17. elebish

    Change TV to receive UHF Channels

    You might be able to cannibalize a vhf/uhf tuner from an old set of the same vintage, feed in the proper supply voltage and agc feedback voltage to the 'feed through caps' to your new tuner since most tuner voltages are the same and plug the IF output from that tuner into the existing IF input...
  18. elebish

    Fluke 179 Repair

    If there is a function or mode selector switch, clean it first. The next thing to look for would be a fusible device internally or a burned component at the input. Also look for a bad connection by wiggling wires and components. Ed.
  19. elebish

    Iwatsu SS-5711

    Let me know if replacing the 2 caps remedies the problem. It should but you may have to readjust focus 1 and 2 and the front panel focus along with the astig adjust. Adjust the front panel focus to the center position before making the other adjustments, then the front panel focus should be...
  20. elebish

    How to power an LED, NEED CLARITY.

    Some notes to remember: Current can not flow without a source of voltage (potential). All purely resistive loads will draw current according to the voltage applied. Too much voltage = too much current, so potential is paramount to proper operation. Current is critical in a LED. As for the LED...
Top