Ruark Vita Audio R1 dab radio powers up momentarily/ only sometimes /poor sound

[rh100605]

I received a Ruark R1 Mk1 radio that showed the first screen and then powered down. I measured the Ruark power adapter output which showed 12 volts but near zero when connected to the radio.
I thought it had to be an adapter loading/overcurrent trip problem so changed adapters to a 12volt 2 amp version. The radio powered up !
It was drawing 1.25amps at low volume and the sound was not good.

The final audio amplifier is a 7watt stereo analogue bridged device ( ST TDA7266 Stereo Audio Amplifier 15 pin). It was warm even at zero volume and cooled down when I removed the speaker connector, so I replaced it with an ST device from eBay.
Be careful not to damage the PCB. Cut the pins on the old one, remove the pin stubs from board, use solder braid to clean the holes replace the heatsink paste and only resolder when then bolted to heatsink.

The radio now draws 400ma at listenable volume and works with the original power supply.
This problem will also apply to the R1 Mk2 and Mk3 and probably the R2 Mk1/2/3 as they all use the same final audio amplifier.
Hope this helps

[Timcarter50]

Hi, and thank you for this post. I was not a member of this group, but have now joined.

I have had a Vita R1 for a long time and last month it gave up the ghost. Every time I powered-on it burped a few times and then gave up. I have been so in love with this radio I decided to look for any possible causes before throwing it out. I found your post and read with great interest.

As a result, I purchased a TDA7266 from e-bay. I also found what I thought were two leaky capacitors (470uF and 4700uF) and ordered some of those as well (sadly I couldn't order one of each, so now have 9 spares of each if anyone is in need). Whilst having worked in the TV trade many years ago, and then computing, I was lost with regard to signal checks and the like you were undertaking, but felt reasonably confident to replace the chip and caps.

30 mins later we were all done and the Radio is back in use. Thank you.

I now need to look at doing something about the display, this gave up some years back but maybe there is something reasonable I can undertake in this regard.

Thanks again.

[rh100605]

Tim,
Thanks for sharing your experience with the R1 radio. I have tried to assemble all Ruark/Vita audio faults in one place on eevblog.
Any more experience you have with Ruark radios/speakers please post here.

The R1 Mk1 uses a 1602 parallel bus LCD display that is readily available on eBay. Beware the LCD is a standard size but the pcb it is mounted on has small variations in mounting dimensions. You will need to remove the  Ruark daughter board that has an IDC socket for the flat cable connector.

Alternatively, if it is just the back light, rectangular leds are available.

If your R1 is a Mk2 model the LCD is a custom SPI device. Replacing the backlight is described on eevblog. Search for Ruark vita audio.
Happy fixing