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  • 6v pilot lamp

    From UFO@21:1/5 to All on Wed Mar 13 11:11:16 2024
    Trying to locate replacement bulbs for an old Wards / Airline transistor
    radio, they are 6.3V
    but only 20mA rated. Higher rated current lamps are out there, but in this design they dim the bulb when you tune a station, so looks like they must be that
    rating, which also saves battery power.

    I thought an 1175 lamp would do but the current is wrong. It has to be a T5 screw type
    socket. Could not locate a bulb number for it...any ideas?

    This is a pic. https://ibb.co/Bzxt7mb

    The front bulb is what came out of the radio 6.3v 20mA. The back one is a
    type 47, 6-8v 100mA way to big.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From jim whitby@21:1/5 to All on Wed Mar 13 16:45:34 2024
    Trying to locate replacement bulbs for an old Wards / Airline transistor radio, they are 6.3V but only 20mA rated. Higher rated current lamps are
    out there, but in this design they dim the bulb when you tune a station,
    so looks like they must be that rating, which also saves battery power.

    I thought an 1175 lamp would do but the current is wrong. It has to be a
    T5 screw type socket. Could not locate a bulb number for it...any ideas?

    This is a pic. https://ibb.co/Bzxt7mb

    The front bulb is what came out of the radio 6.3v 20mA. The back one is
    a type 47, 6-8v 100mA way to big.

    Closest thing I could find.

    Lamp # 342
    6V AC/6V DC 0.2W 0.04A T1 3/4 blub

    from
    mcmaster.com/products/miniature-screw-base-light-bulbs/voltage~6v-ac/





    --
    Jim Whitby


    When people say nothing, they don't necessarily mean nothing. ----------------------
    Mageia release 9 (Official) for x86_64
    6.6.18-server-1.mga9 unknown
    ----------------------

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ehsjr@21:1/5 to UFO on Wed Mar 13 15:23:58 2024
    On 3/13/2024 11:11 AM, UFO wrote:
    Trying to locate replacement bulbs for an old Wards / Airline transistor radio, they are 6.3V
    but only 20mA rated. Higher rated current lamps are out there, but in this design they dim the bulb when you tune a station, so looks like they
    must be that
    rating, which also saves battery power.

    I thought an 1175 lamp would do but the current is wrong. It has to be a T5 screw type
    socket. Could not locate a bulb number for it...any ideas?

    This is a pic.  https://ibb.co/Bzxt7mb

    The front bulb is what came out of the radio 6.3v 20mA. The back one is a type 47, 6-8v 100mA way to big.



    Might be time to consider replacing the bulb with
    an LED and series current limiting resistor. The
    mechanical part - mounting the LED - might be a little
    challenging, but determining the resistor size is
    straight forward. If you're not sure of that, we can
    help you here.

    Ed

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Sjouke Burry@21:1/5 to UFO on Wed Mar 13 20:23:22 2024
    On 13.03.24 16:11, UFO wrote:
    Trying to locate replacement bulbs for an old Wards / Airline transistor radio, they are 6.3V
    but only 20mA rated. Higher rated current lamps are out there, but in this design they dim the bulb when you tune a station, so looks like they must be that
    rating, which also saves battery power.

    I thought an 1175 lamp would do but the current is wrong. It has to be a T5 screw type
    socket. Could not locate a bulb number for it...any ideas?

    This is a pic. https://ibb.co/Bzxt7mb

    The front bulb is what came out of the radio 6.3v 20mA. The back one is a type 47, 6-8v 100mA way to big.


    I replaced two of those fm stereo tuning
    lamps with two red leds.
    Still working after 20 years.........

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From UFO@21:1/5 to All on Thu Mar 14 00:31:10 2024
    Been hearing that a lot for responses.
    Since the LED needs I guess 1.5V to be on,
    and can burn out with too much voltage, it
    did not seem to be a suitable option.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Arie de Muijnck@21:1/5 to UFO on Thu Mar 14 10:06:08 2024
    On 2024-03-14 05:31, UFO wrote:

    Been hearing that a lot for responses.
    Since the LED needs I guess 1.5V to be on,
    and can burn out with too much voltage, it
    did not seem to be a suitable option.

    That is why series resistors are always used.
    R = (Vin - Vled) / Iled

    Arie

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From legg@21:1/5 to UFO on Thu Mar 14 07:58:44 2024
    On Wed, 13 Mar 2024 11:11:16 -0400, "UFO" <tech@parts-link.com> wrote:

    Trying to locate replacement bulbs for an old Wards / Airline transistor >radio, they are 6.3V
    but only 20mA rated. Higher rated current lamps are out there, but in this >design they dim the bulb when you tune a station, so looks like they must be >that
    rating, which also saves battery power.

    I thought an 1175 lamp would do but the current is wrong. It has to be a T5 >screw type
    socket. Could not locate a bulb number for it...any ideas?

    This is a pic. https://ibb.co/Bzxt7mb

    The front bulb is what came out of the radio 6.3v 20mA. The back one is a >type 47, 6-8v 100mA way to big.


    Used to be a common part for analog meter illumination, so keep
    looking. Was once a radio shack number.

    RL

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From UFO@21:1/5 to All on Thu Mar 14 09:20:32 2024
    Yes, Radio shack # 272-1140

    https://www.ebay.com/itm/325945990509

    No longer availabe.


    Used to be a common part for analog meter illumination, so keep
    looking. Was once a radio shack number.

    RL

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ehsjr@21:1/5 to UFO on Thu Mar 14 17:03:50 2024
    On 3/14/2024 12:31 AM, UFO wrote:

    Been hearing that a lot for responses.
    Since the LED needs I guess 1.5V to be on,
    and can burn out with too much voltage, it
    did not seem to be a suitable option.

    Here's a diagram:

    +6V ---resistor---LED---ground

    Assuming a red LED you need roughly 1.5 volts
    applied to it. That means the resistor has to
    drop about 4.5 volts. We want the current to
    be 20 mA or less, so we'll choose 10 mA. The
    formula to determine the resistance is R=E/I
    where E is the voltage to be dropped and I is
    the current through the LED. So R = 4.5/.010
    That equals 450 ohms, and the closest standard
    value is 470 ohms, which will work just fine.
    A 1/8 watt resistor is the smallest trough hole
    size and may be easier to fit in than a 1/4 watt.
    It depends on what you have on hand that will physically
    fit - the resistor will use only about .05 watt

    The current through the LED does not have to
    be exact - anything from say 2ma (often much
    lower, depending on the LED) to 20mA will light
    it up nicely. If you want to use a white LED
    you can. A white LED needs roughly 3.2 volts
    so the resistor value changes to roughly 280 ohms,
    which means using a 270 or 330 ohm standard size.
    I'd use 330.

    Ed

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)