Panasonic SA-BTT270

SA-BTT270

The SA-BTT270 is a blu-ray disc home theatre sound system manufactured in Malaysia by the Panasonic Corporation of Japan, Osaka. Essentially, it is a blu-ray DVD player with built-in surround sound digital amplifier. The front, centre, and surround channels are 160-watts each (with 3-Ω speaker loads), and the subwoofer output is 200-watts (with 3-Ω speaker). It also has FM radio tuner, SD card slot and a USB socket to play music/video stored on a USB memory stick. For iPod/iPhone users, there is a slide-out tray with interface to plug-in your gadget. The dimensions are 430 mm × 38 mm × 279 mm, and mass 2.7 kg.

Review

Power Button

Panasonic design and engineering is of course legendary, and this lovely design comes in a very slim profile for the minimalist who does not want to clutter his living room with a stack system and excessive wiring. The power button is at the top because it totally does away with stack systems.

Digital amplifiers are very common and this unit uses the C1AB00003582 speaker driver ICs. Each IC drives a pair of speakers and consequently they use three chips to cover all the surround channels. For the pulse-width modulation (PWM) processor, they use the C1AB00003610, which provides signals for all three driver ICs. Interestingly, the active cooling system fan is also linked to the amplifier circuitry; hence the fan comes ON as the amplifier load increases. With Panasonic, the level of sophistication is always very impressive and this design ticks all the boxes for me.

There are two options to connect to the broadband, either with a wire, or wirelessly (accessory required). This then allows one to enjoy internet services, and through VIERA CAST, one can enjoy watching YouTube. NETFLIX can also be accessed directly by pressing a dedicated button.

Slide-in Tray
iPod/iPhone Interface

I was not able to test this part as I do not have any compatible gadgets. As you can see, there is this slide-out tray with interface for your favourite Apple iPhone or iPod. My friend Rufus absolutely hates iPods and iPhones, and just out of spite he wanted to use it as an ash tray, though he does make a point, that had it been an interface for a Samsung Smartphone, it would have been more useful.

Volume Buttons

One of the nicest functions I discovered about this unit is that you can plug in your USB stick with MP3 music and it automatically senses the stick and switches to the relevant mode to play music. One then simply has to press the play button behind the flap to play... Since I do not have a remote control or a TV I thought this was a good bit of thoughtful programming. In contrast I have another DVD player that requires navigation through a plethora of menus before you can listen to music.

One of the biggest advantages of this model is the powered subwoofer output, which saves you money but also reduces the wiring overhead compared to active subwoofer speakers. It is rare to find a Panasonic unit with problems, however I managed to snag this one for a couple of pounds in the spares and repairs section. It was damaged due to misuse by the previous owner, and in the following pages of the article you can see the repairs that I carried out.

Price/eBay

These units are usually available for sale on eBay and a unit in good working order together with the original speaker and remote control can cost around one hundred pounds. If it is hardly used and still with the original packaging, then it can be worth a lot more. It is popular because its tiny speakers do not take much space and yet they produce a big sound.

The one thing to watch out for is dust, because it has an active cooling system with built-in fan and consequently a pre-used unit will likely be clogged with dust. My one was completely full of dust and overheating, and even after vacuuming and cleaning I still managed to capture some dust in my photographs!

I bought this because it was broken and going cheap and I was curious to see the technology they employ in these slim modern designs. The unit was not switching ON, and there was neither the remote control nor the speakers with it. Nobody wanted it because they probably thought that the amplifier was burnt. For six pounds it was a great bargain, because even if it could not be economically repaired, it had a lovely slim case that I could use for my preamplifier circuit projects. As it turned out, I was lucky because it had a very interesting fault consisting of a burnt board due to overload. You can see the inside engineering and the repairs I carried out in the following pages of this multi-page article.

This Article Continues...

Panasonic SA-BTT270
Electronic Engineering
Inside View
Digital Amplifier Board
Power Supply Design
Power Supply Fault
Repair
Tray Not Opening
Heatsink and Fan
Panasonic Error F61
Reset
Display Fault
Back Sockets