Good to hear you were able to fix this weird issue!
I'm also thankful that my problem help others to avoid such difficulties!

exxos wrote: ↑Mon Jan 21, 2019 9:09 pm Which ROM was it you installed, this one ? https://www.exxosforum.co.uk/atari/store2/#0049 (0049) I will burn a new ROM here and see if I have the same issue here... Then at least I know the ROM file I used is good or not...

[0053] German

Very strange... I don't see how TOS104 works at 16MHz but not TOS206. Its like TOS206 ROM is corrupted, but you said it works at 8MHz ? No, TOS206 never worked (not with 16MHz and also not with 8MHz -> same behaviour) Can you boot TOS104 and run GB6 for a couple hours and see if TOS104 is stable at...

Thanks.. It looks like the yellow line is the booster pin 1 ? No, its Pin 39! The signal doesn't look as good as it should be. I suggest you put a 68R in series with the wire going to pin 39 of the shifter... try again... if still problems, add another 68 and try again... Tried it with same result:...

On Pin39 of the Shifter IC as suggested! You haven't read my post fully as I asked for 2 readings... https://www.exxosforum.co.uk/forum/viewtopic.php?f=23&t=1546&p=17068#p17044 You are right,sorry! My test setup: VPspgFk.jpg Signals (Line 1 Pin39 Shifter IC, Line 2 Booster PCB): g66q4km.png...

exxos wrote: ↑Mon Jan 21, 2019 10:21 am Where are you measuring it ?

On Pin39 of the Shifter IC as suggested!

exxos wrote: ↑Sun Jan 20, 2019 9:10 pm

leon22 wrote: ↑Sun Jan 20, 2019 9:08 pm I interpreted it right! Also tried this -> same result!

OK, so need to see the 16MHz waveform output from the shifter pin 39, to pin 1 on the GAL top right of the booster PCB.

Ok, here is the 16MHz signal:

exxos wrote: ↑Sun Jan 20, 2019 9:02 pm The wire which goes to the ROM board, place 68R resistor in series with that wire.

I interpreted it right! Also tried this -> same result!

No I mean TOS104 (sorry for the typo)! So I can boot in 16MHz + 8MHz mode to TOS104 and never to TOS206! The only possible modification is wiring a 68R resistor in series with ROM CE to the dualtos board as I have seen issues there recently. You probably would have to send me your motherboard to di...

No I mean TOS104 (sorry for the typo)! So I can boot in 16MHz + 8MHz mode to TOS104 and never to TOS206! The only possible modification is wiring a 68R resistor in series with ROM CE to the dualtos board as I have seen issues there recently. You probably would have to send me your motherboard to di...