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  1. elebish

    I just replaced the capacitors in two Gateway monitors and turned on then died again

    I would check for dc across the pads where the caps were after cleaning of that area. Since the caps were rated for 50 volts dc, you should have less than that unless the volts increased because of failure possibly due to regulation problems. I would also check for an ac component in the dc. I...
  2. elebish

    Anyone have any oscilloscope recommendations?

    You mentioned salvaging parts from a dump on base. We had a huge dump near my home town that many companies dumped their old and unneeded parts including Bell Telephone, Western Electric and some of the local radio stations. I found lots of useful stuff there as long as the night guard didn't...
  3. elebish

    Anyone have any oscilloscope recommendations?

    Great story of your start in this field of electronics! I was raised in Pa but lived in MO since 64 and worked at McDonnell since 66. I like the Midwest so much better than PA. Every time I go back to PA to see the folks, I get sick in the stomach to see how the place is falling apart and the...
  4. elebish

    Capacitor In Line?

    The capacitor is acting as a filter to smooth out the peaks of the 'sawtooth' waveform that is produced by the diode rectifiers (assuming that is what you are referring to). The average DC output will read approx. 1.4 times higher than the unfiltered pulsating DC with no load applied. Example: A...
  5. elebish

    Anyone have any oscilloscope recommendations?

    You sound just like me when I got started in Elect. I hated high school but ate up tech school and joined the Air Force and became a tech on the F105 in Germany after going through school at Chanute, Ill. I went to work at McDonnell in 66 and McDonnell merged with Boeing in 99. I worked in the...
  6. elebish

    Floating current source

    Does your requirement have any thing to do with the mains ground or common?
  7. elebish

    Vacuum Tubes

    Actually, a tube will generate a signal that looks just like the signal applied to the control grid. It does this by varying the current drop across the plate load resistance which is the output signal. All this is dependent of the plate voltage, load resistance, cathode potential and the grid...
  8. elebish

    I need help,AC/AC power transformer,please take time and read...

    Wow, Croatia! Been there a number of years ago. Great people!
  9. elebish

    Anyone have any oscilloscope recommendations?

    Wow! I built one of these back in 58 when going through radio and TV school in PA.
  10. elebish

    Anyone have any oscilloscope recommendations?

    I have a like new TEK 2465BDM with all the goodies (400MHZ) I picked up for $550. The books were still sealed in their plastic wrappers. This is a serious scope but not for beginners. I also have 2 Iwatsu's that are very high quality and great for T.S. They both are SS5711D's. You may be able to...
  11. elebish

    Kenwood TS-450 Final Bias adjust

    Just hook an ammeter in series with your 50 ohm dummy load at the antenna terminals. I believe 250 Ma is the reading at idle according to you jpg sheet.
  12. elebish

    Tektronix 2445 scope problem

    The deflection circuit for the crt works for both the trace and the readouts. Sounds like a horiz scan problem. Check the voltages at the pins on the side of the neck of the crt. Voltages will be high, around 200 to 300 volts dc.
  13. elebish

    Need Help on my 21" crt tv red retrace line

    Retrace lines are caused by a defective blanking circuit or the brightness turned up too high. There is both, horiz and vert blanking circuits. These circuits blank out the crt during scan retrace. Suspect a bad electrolytic capacitor in one of those circuits.
  14. elebish

    Sony HT amplifier/receiver repair

    Put a 75 watt incadescant 115 volt bulb across the ac fuse with the fuse removed so you can work with power on. If a short exists somewhere, the bulb will light up bright to act as a shunt to keep your boards from being damaged. Then isolate the short by removing the output transistors or large...
  15. elebish

    Tektronix 2235 reduced horizontal sweep

    Check the horizontal sweep output transistors and wiring going to the (side) pins on the neck of the crt. These crt's generally have electrostatic type deflection circuits that contain a voltage of about 200 to 300 dc. Be careful not to break these pins or the neck!
  16. elebish

    UT61E multimeter - milliamps function not working

    Check all low value resistors for proper value.
  17. elebish

    Transistors... help

    Terminal 1 is Emitter. terminal 2 is Base and case is Collector. These are typical PNP silicon audio output T03 style transistors similar to an ECG 61.Collector voltage should be around 140 VDC max and Collector AMPS at 20 max. Wattage around 250 when properly heat sinked and frequency max is 2...
  18. elebish

    Help with identifying resistor - yet again

    I believe Alec is correct. That resistor is probably an emitter resistor which is normally a small value. The fact that it is a wire wound tells me that that circuit may not be rf, but dc only, as a wire wound can act as an inductor in an rf circuit.
  19. elebish

    Help identifying a resistor

    .5 % is probably not right since most consumer products do not use such small tolerance components. That 5th band could be a MTBF code. The 4th band is hard to distinguish between yellow or gold. Look at some of the other resistors similar to the one in question and measure to determine what the...
  20. elebish

    Hope I didn't make too big a mistake with my radio...

    That was not a diode, it was a 5600 ohm resistor. Re-connect the resistor and disconnect the detector diode that follows the IF section. Couple your audio through a 4 ufd @ 25 vdc across the 2 outside terminals of the volume control. Make sure the (ground) negative side of audio input goes to...
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