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Re: Falcon Restoration Project

Posted: 09 Nov 2023 21:18
by hunsra
Maximilian wrote: 09 Nov 2023 18:26 You cab use a no so sharp needle and just try to ever so lightly try to move a pin, if the pin moves with the needle, it is loose.
No need to continuity check if there is no apparent damage, and it can give you a false hope of security because if the pin isn't soldered correctly if will give problems when the machine heats up or cools down..
Ah, makes sense. I'll give that a try. Thanks.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 15:06
by hunsra
Maximilian wrote: 09 Nov 2023 18:26 You cab use a no so sharp needle and just try to ever so lightly try to move a pin, if the pin moves with the needle, it is loose.
No need to continuity check if there is no apparent damage, and it can give you a false hope of security because if the pin isn't soldered correctly if will give problems when the machine heats up or cools down..
@Maximilian, there was indeed one pin not solidly connected (pin 15), although I don't think it's connected to anything anyway (according to schematic). Thanks for the suggestion. Unfortunately, still no video output. I'm going to go through the Phantom mod documentation and see what might need reversing.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 15:12
by stephen_usher
You may not have video output but do you have bus activity?

You may be fighting multiple faults so concentrate upon one thing at a time.

If you see data on all the address lines and all the data lines around the board and you see the correct type of signal on the CPU control lines then you can move on from the CPU to other parts of the system. Trying to diagnose everything at once is a hiding to nothing.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 15:14
by rubber_jonnie
stephen_usher wrote: 10 Nov 2023 15:12 You may not have video output but do you have bus activity?

You may be fighting multiple faults so concentrate upon one thing at a time.

If you see data on all the address lines and all the data lines around the board and you see the correct type of signal on the CPU control lines then you can move on from the CPU to other parts of the system. Trying to diagnose everything at once is a hiding to nothing.
I have to agree with Stephen here, if you chase everything you end up with nothing.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 15:47
by Steve
@stephen_usher @rubber_jonnie but we do know he doesn't have his 32mhz clock line due to L132 being removed. So I'd start there.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 16:17
by hunsra
rubber_jonnie wrote: 10 Nov 2023 15:14
stephen_usher wrote: 10 Nov 2023 15:12 You may not have video output but do you have bus activity?

You may be fighting multiple faults so concentrate upon one thing at a time.

If you see data on all the address lines and all the data lines around the board and you see the correct type of signal on the CPU control lines then you can move on from the CPU to other parts of the system. Trying to diagnose everything at once is a hiding to nothing.
I have to agree with Stephen here, if you chase everything you end up with nothing.
Thanks @stephen_usher and @rubber_jonnie. That's next.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 16:23
by rubber_jonnie
Steve wrote: 10 Nov 2023 15:47 @stephen_usher @rubber_jonnie but we do know he doesn't have his 32mhz clock line due to L132 being removed. So I'd start there.
Well, no clock = bad juju, so definitely a good place to start :)

Re: Falcon Restoration Project

Posted: 10 Nov 2023 16:31
by stephen_usher
rubber_jonnie wrote: 10 Nov 2023 16:23
Steve wrote: 10 Nov 2023 15:47 @stephen_usher @rubber_jonnie but we do know he doesn't have his 32mhz clock line due to L132 being removed. So I'd start there.
Well, no clock = bad juju, so definitely a good place to start :)
Also, no clock == no nothing.

Re: Falcon Restoration Project

Posted: 10 Nov 2023 16:46
by hunsra
stephen_usher wrote: 10 Nov 2023 16:31
rubber_jonnie wrote: 10 Nov 2023 16:23

Well, no clock = bad juju, so definitely a good place to start :)
Also, no clock == no nothing.
So far, all of the address lines I tested are high, but yes, L102 is missing. I probed on the oscillator side and it's coming out 32MHz, so I'll either bridge it as suggested or get a replacement. The I can't make out the value for L102 in the schematic I have (see pic). Does anyone know the proper value?

L102.jpg

Re: Falcon Restoration Project

Posted: 10 Nov 2023 16:54
by stephen_usher
It's probably there to reduce harmonics and probably the same as L104.