Silvercrest SIRD 14 E1 Internet Radio muted - Repaired

[Datman]

Hi all.
I'm sharing an experience of mine, which could be useful to someone.

Last night I opened* the LIDL Silvercrest SIRD 14 E1 radio, which arrived a few days ago from Germany (purchased from LIDL.de via mailboxde.com for €124.05 in total):


https://www.lidl.de/.../silvercrest.../p100341448

to dim the white circles around the knobs, which do not dim together with the display. To do this, I inserted a 47 ohm SMD resistor in series with the common of the 4x 100 ohm resistors in series with each of the 4 LEDs (2 for each encoder).

I tested it, closed it, tried again and put it on the bedside table, leaving it on at night. At 4:45 Teo, my cat, woke me up meowing and I realized that the radio had turned off. I turned it back on, but it remained silent, even though all the menus worked properly. This morning I continued testing and I realized that nothing was coming out of the headphone jack, nor from the line jack. Nothing could be heard even when putting a signal on the Aux input.

I opened it again (this time removing the 8 screws with the electric screwdriver and the long bit!) and I also removed the internal plastic panel that covers the electronics (the one on the front panel is only for control). I removed the electronics, unsoldering the coaxial cable of the whip antenna (which also has a small internal ground plane, made with a sheet of copper!) and I started to observe the board.

I noticed the SC2314 integrated circuit, which I discovered to be the switch/preamplifier/equalizer/loudness controlled via I2C. Going to check the power supply on pin 1, I noticed that it was missing! It came from a 78M08, which had nothing at the input... Power to it came from a SOT-23 marked 3415E, a P-channel mosfet. Since it had a Vgs of about -9V it should have been in full conduction, instead it was blocked... Tested with the Chinese component tester, it was a simple capacitor! I replaced it with an AO3401, of which I had purchased from Aliexpress about ten pieces years ago, and it worked!

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*: to open it, you have to lift and remove the front grille, using pointed tweezers or the tip of a burnished electric screwdriver screw on the side, then unscrew the 8 cross-head screws in the deep holes; then, using a sturdy blade (e.g. Argentax n.44), you lever to remove the entire light gray part (including the speakers) from the dark gray rear shell.