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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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13th Mar 2019, 1:11 pm | #1 |
Pentode
Join Date: Jun 2017
Location: Basildon, Essex, UK.
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Bulbs for Racal RA1772 encoder unit
Has anyone got any idea where I could obtain suitable 690w 14v replacement filament bulbs for the RA1772 encoder unit? Would leds be suitable replacements
and if so what type? Thanks Hugh G1AUR |
13th Mar 2019, 1:39 pm | #2 |
Dekatron
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Location: Heckmondwike, West Yorkshire, UK.
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Re: Bulbs for Racal RA1772 encoder unit
I think these are they: https://vintage-radio.net/forum/showthread.php?t=114340
Farnell also have them: http://www.farnell.com/datasheets/29809.pdf |
13th Mar 2019, 2:46 pm | #3 |
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Location: Leominster, Herefordshire, UK.
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Re: Bulbs for Racal RA1772 encoder unit
Farnell link only goes to datasheet. The Farnell cat. no. there is no longer recognised.
There is this: https://uk.farnell.com/lux/n9951903/...m%2Fw%2Fsearch but there's some confusion as to whether it's 14V or 24V! Or you could get inventive with these, perhaps? https://www.ebay.co.uk/itm/LAMP-T1-1...EAAOSw-jFZ6etF
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13th Mar 2019, 3:38 pm | #4 |
Pentode
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Re: Bulbs for Racal RA1772 encoder unit
Many thanks for your advice gentlemen!
73 Hugh G1AUR |
13th Mar 2019, 4:35 pm | #5 |
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Re: Bulbs for Racal RA1772 encoder unit
An LED and a resistor ought to last indefinitely. As the sensor will be a phototransistor, it's worth looking up it's spectral sensitivity and picking an LED to suit the best wavelength.
David
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13th Mar 2019, 8:51 pm | #6 |
Dekatron
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
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Re: Bulbs for Racal RA1772 encoder unit
Tubular 14V LES bulbs were used in the car radios made by for Ford by Plessey in the late 1960's I have a couple somewhere in the loft that I will never use again and could salvage the bulbs from them. I am not familiar with the Racal encoder unit. Is the bulb wattage/current and envelope configuration critical? How many do you need? Somewhere I do have some low wattage LES bulbs that I got some years ago for the dolls house I made for my daughter and must have some spares somewhere, but I think they are 12V. A bit busy decorating at present but I can have a look at the weekend if you can't find anything suitable.
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13th Mar 2019, 11:23 pm | #8 |
Dekatron
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
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Re: Bulbs for Racal RA1772 encoder unit
While looking for something else, I found a box with a couple of NOS 14V 0.75W LES bulbs (RS code 586 093) that I have had for more than 40 years and not needed. If they are any use, PM your address and I will stick them in the post FOC.
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15th Mar 2019, 7:58 pm | #9 |
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Re: Bulbs for Racal RA1772 encoder unit
I reckon this is close enough - draws a little more current, but that shouldnt be an issue
https://www.ebay.co.uk/itm/14v-50ma-...frcectupt=true
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23rd Mar 2019, 8:50 pm | #10 |
Pentode
Join Date: Jun 2017
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Re: Bulbs for Racal RA1772 encoder unit
Thanks to everyone for response and apologies for all advice and offers.I should now be able to find the type. Emeritus thanks for your offer apologises for late response..call of work...!
73 Hugh G1AUR |