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Raytheon Tubes

Discussion in '"Boat Anchor" & Classic Equipment' started by KF5DDW, Sep 24, 2020.

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  1. KF5DDW

    KF5DDW Ham Member QRZ Page

    Found the alignment tool, radio shack. For all IF/RF transformers, or so it says.
    WA1GXC likes this.
  2. KF5DDW

    KF5DDW Ham Member QRZ Page

    On making an alignment load the instructions are 1000 ohm non inductive resistor and .005 uuf cap. Is that a 5pf or what?
  3. KF5DDW

    KF5DDW Ham Member QRZ Page

    The instructions for the alignment load is 1000 ohm non inductive and .005 uuf cap. Is that supposed to be 5 pf ?
  4. NQ8J

    NQ8J Ham Member QRZ Page

    I believe that's a typo in the TR-3 and TR-4 manuals. TR-4C and R-4B manuals specify 0.005uF. I've used 0.0047uF for the alignments I've done.
    WA1GXC likes this.
  5. KF5DDW

    KF5DDW Ham Member QRZ Page

    Why did you change to the 0.0047uf?
  6. WA1GXC

    WA1GXC Ham Member QRZ Page

    .0047 is now an industry-standard value.

    The EIA (Electronics Industry Association) has a standard-value list for resistors and capacitors.
    Whereas .05, .005 uF was common, it is relatively unavailable in non-precision components today.

    It's derived from statistical range of true value with 10% or 20% tolerance components and their overlap of values.

    So, you see resistors at 15, 18, 22, 27, 33, 39, 47, 56, 68, 82 ohms--If you look at 10% variation, you've got the target values covered. In most
    ordinary applications, the small divergence from a round number is inconsequential.

    Same in capacitors, although some even-number values still common.

    When you get to components with 5% or tighter tolerance, there are exact values available, often in military or special-order components,
    and priced astronomically accordingly.

    Old gear from WW II thru 1970's has round-number values prevalent, but that's now historically archaic.
    NQ8J likes this.
  7. KF5DDW

    KF5DDW Ham Member QRZ Page

    Well ok. I try to learn something everyday, I believe this will check that box. Thanks

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