Advise needed on Sinclair PC200

[niels]

Hello everyone,

I own a Sinclair PC 200 base unit which I would like to get running, but there are some problems. Perhaps you can help me ?

When I turn on the unit, the red power led lights up and after a second or-two it starts flashing the drive A led (and the floppy drive seeks). After another couple of seconds, the green drive B led starts flashing for a second. Then, the Sinclair starts beeping (in repeat) and the num lock key flashes.

I tried connecting the TV out of the Sinclair to a TV (composite video) but get no signal,
is it right to connect it to the composite input of a TV ?

I have no software for the PC200, but I reckoned it should at least give me some error message before I go sort out any software

Thanks,

 

[JohnElliott]

No; the television output is RF, not composite. You will also need to set the DIP switches appropriately.

 

[niels]

Thanks,

I configured the DIP switches and connected the PC200 to a TV Tuner, Really nice to see the start-up screen of a PC200!

Only, the original beeping problem is still there;

It is asking me to "Check keyboard" and the PC200 keeps beeping; I took a look under the lid but there cannot possibly be something wrong with the keyboard.
Is there something else I could do, is it a problem related to the CMOS battery ?

 

[JohnElliott]

There is no CMOS battery. 'Check keyboard' means the keyboard didn't pass its power-on self test, most probably because a key is being pressed or is stuck down.

 

[niels]

Thanks,

I took a good look and could not find any stuck keys and they all seem to "click" just fine.
I also blew some dust away between the keys but that did not help. Also both the ribbon cables are inserted in their slots; Do you think I could use contact spray to clean up the electronics ?