Broken Turbo-r RTC chip.

Resident (39)

11-12-2016, 21:36

Hello everybody!

Well, probably i have broken RTC chip, in my MSX FS-A1ST turbo-r.

I install two brand new SRAM backup AA-batteries, accidentally wrong way in battery hole! Stupid me
Immediately i changed the batteries, the right way. Perhaps too late.

When i save clocktime and screen modes in SRAM and then
push reset button, everything is OK.
But all settings will be lost, when i turn power off.

Can the wrong SRAM battery polarity, to break motherboard?
and what might be broken?

I would be grateful for comments.

Regards
Marko

By Manuel

Ascended (19220)

11-12-2016, 22:14

I never heard of a broken RTC.... I'd first think of bad contact of the batteries in the socket. Perhaps there's some corrosion on the connectors?

By RetroTechie

Paragon (1563)

12-12-2016, 01:32

Both ST and GT have a reverse polarity protection diode AND a 1k resistor in series with the battery. No way the few mA that gets through, could kill anything inside the machine (imho). So have a look at contact issues first like Manuel said.

By raymond

Hero (622)

12-12-2016, 07:29

Or the new batteries are empty?

By meits

Scribe (6530)

12-12-2016, 11:39

I had some oddities a little while ago as well... The batteries weren't correctly inserted/corrosion... Either way, after some fiddling with the position of the batteries all was well...

By Edi-73

Resident (39)

12-12-2016, 19:06

I tested several batteries. Did not help. Two AA-batteries gives 3.10 volts, so it's normal.
I check contact surface, no corrosion. Just in case, i cleaned contacts. Did not help.
Maybe i must open my turbo's and look inside. Could it be reason for bad capacitor?

Thanks for the replies

By Jipe

Paragon (1586)

12-12-2016, 19:38

then you opening check with a mulimeter the voltage on the solder of red and black wire
the making of battery is not the same the older and you have a false contact in the turbo -r

By Edi-73

Resident (39)

12-12-2016, 20:05

I forgot one thing.
I measured the voltage in battery contacts, when the batteries were not in place. I did not get any voltage, even when power was turned ON. Should it be?

Thanks for the advice

By meits

Scribe (6530)

12-12-2016, 21:32

Edi-73 wrote:

Thanks for the replies

I had the same. Still the batteries didn't make good contact... Wiggle them a bit.

By gdx

Enlighted (5997)

13-12-2016, 00:36

Clean contacts (batteries too) with alcohol by rubbing well and check red and black wires inside.

By SonyTEL

Rookie (18)

13-12-2016, 02:59

It is obligatory a false contact ... In the contacts between the batteries and the turboR.
I use these batteries that can last 10 years and more!
Https://www.amazon.com/Energizer-Ultimate-Lithium-Batteries-...