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Unidentified componets

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SG-1:
Can anybody help identify the two componets closest to the LED ?   I first thought one was a zener, to regulate the output of the LED,  but a test proved that incorrect.  I now think it could be a Transient Voltage Suppressor ?    Thanks for any help.

SG-1:
I suppose it would be helpful to mention the test.  I applied 10,20, & 30VAC to the inputs & the voltage across the LED changed from 2.2, 2.7, & 2.9 VDC.  The LED brightness changed appreciably with the voltage.

Mechatrommer:
i think you got the label backward. the bottom part (yellow) is capacitor to stabilize the rectifier output and the top part with striplines is resistor to drain the caps, i dont like it, i just prefer it to be removed (waste of energy). though i'm not 100% sure since i cannot trace where the Vac going (under the rectifier)

A Hellene:
The LEDs are current-driven devices --they are not voltage-driven ones.

Anyway, the schematic of this device seems to be very simple:

The four input resistors are 470Ω/0.5W each and they form an input bias resistor of 1K88/2W, which feeds the LED with a current of 8..21mA minus 1mA the small bleeding resistor (color coded: Red-red-green-brown: 2.25KΩ) draws.

The components that are in parallel to the LED are:
1. A rather beefy (for the size) capacitor of a value between 0.47 .. 2.2μF to make the LED light smoothly (and not flicker due to the AC drive), and
2. A bleeding resistor of 2K25 to discharge the capacitor quickly when the power is removed, in order to prevent the LED from fading out.


-George

SG-1:
Thank you, Mechatrommer & A Hellene,   the fourth colour band was throwing me off on the bleeding resistor.

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