Panasonic FS-A1 black screen

Supporter (8)

06-04-2014, 20:05

Hi,

I have got a Panasonic FS-A1 from Ebay. It came with genuine PSU and RGB-Scart Video cable. I always get a black screen, I have tested it on two TVs. The following things I already tested:
Voltages are okay: +5V, +12V, -12V. All ICs (74LS..., 6 x MB81464, Z80A, V9938 and ROM) have +5V Power. The SMD-Chips I have not tested yet. On the Z80A Clock is okay: 3,5795 MHz. Reset-Pin is high.
The Power LED is on. I have a PAL-TV (Germany), so there could be Problems with the NTSC-J Video, but if I use the RGB-Video it should not matter, right ?
Does anyone have a circuit - diagram for the Panasonic FS-A1 ?

Greetings,
Ralf

By Manuel

Ascended (19469)

06-04-2014, 20:58

Does the CAPS LOCK work? Does it give sound?

By Daemos

Prophet (2070)

06-04-2014, 20:58

Lets start with the default tests

After you put your MSX on. Do you see the caps lock responding when you press caps?
Do you hear beep. Try to type BEEP blindly and press enter
Also press shift+F1 just to be sure.

By ralf02

Supporter (8)

07-04-2014, 08:44

Hi,

thanks for your advice. How should I test, whether CAPS LOCK works ? Should there be a caps lock LED ? I havn't found it. The other things I will test during the next days.
Is somwhere a circuit plan for the Panasonic FS-A1 available ?

Greeteings,
Ralf

By Manuel

Ascended (19469)

07-04-2014, 09:54

There should be at least 2 LEDs besides the POWER led... a CAPS and a KANA led... usually. I don't know the FS-A1 in detail, though.

By Daemos

Prophet (2070)

07-04-2014, 10:25

Cannot find the circuit diagram of that computer for you.

This computer doesn't seem to have any other leds than power

Uhm ok. Let see if there is any sound. I assume your scart/RGB cable is functional so at least sound should be audible even when the TV has trouble with NTSC/PAL related matters. Turn the MSX on and see if you hear a beep. Otherwise wait for a while and blindly type beep and press enter.

If you have a floppy. insert this into the diskdrive and see if the MSX tries to boot. You will at least hear some motor activity after some time which might indicate that at least some code is being executed.

By Denus

Expert (120)

07-04-2014, 11:17

This maybe?

http://msx.hansotten.com/uploads/msxdocs/panasonicsa1wxsm.pdf

By Daemos

Prophet (2070)

07-04-2014, 11:55

Nope thats the WX. We need the FS-A1 without any suffixes.

By Jipe

Paragon (1614)

07-04-2014, 13:46

see specifications : you have a composite video ( yellow RCA ) try this
http://www.msx.org/wiki/Panasonic_FS-A1

By ralf02

Supporter (8)

08-04-2014, 07:44

Hi,

I already tried to get a picture with Composite Video, but I got a black screen, too. I have an original japanese Computer with NTSC-J, so I am not sure, whether I would get a Picture with Composite Video, maybe only black and white. I am now three days on journey, so I will try on thursday, if the Beep - Sound works. If yes, does it mean, that the V9938 is bad ? I have seen on ebay, that this IC is still available.

Greetings,
Ralf

By Daemos

Prophet (2070)

08-04-2014, 08:24

Quote:

does it mean, that the V9938 is bad ?

not perse. We have to examine that with more little tests I assume that this machine has a RGB or scart port?