PaulJ's H4 Mongrel Build x 2

[PaulJ]

@PhilC , were getting close on the second H4. Hows that 80% H4 coming?

I haven't had any time, still just sitting there mostly assembled.

Well, applied power today and got 20 bombs.. dragrom doesn't put any serial data or screen with text. Current is around 1.5 amps which is normal. So if you power yours up Phil let me know if you get anything beyond my bombs. Will be using the scope and ohm meter to ferret out any issues.

[PaulJ]

@PhilC , to late its alive! its alive!!!. Helps if one populates R908

Is this the first H4 born with SMT GLUE and MMU? Have to check everything out tomorrow and insure there are no defects.... I have to thank @PaulJ_2.0 for suggesting that I tin the SMT pad prior to soldering. Made drag soldering much easier.

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[PhilC]

Well done @PaulJ you beat me on both versions of the board.

Very happy to see it booting.

[Icky]

Nice.

[PhilC]

@PaulJ it might be the photo but check your MMU, bottom right pin next to C3, looks like the pin is on the wrong pad.

[PaulJ]

@PaulJ it might be the photo but check your MMU, bottom right pin next to C3, looks like the pin is on the wrong pad.

Nope, the devices went on well. tinning the pads makes soldering much easier. The glue device had bent leads so it was a little buffer but also installed easily.

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[PaulJ]

Ran all the Atari diagcart tests and everything passes with the except of the parallel port which must have some bad lines.

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[exxos]

I don't think anyone has tested the parallel or midi ports yet.

[PaulJ]

I believe it tested ok on the H4-1. So I'll have to take a look at the -2.

[PaulJ]

@exxos , what's the scoop with the MFP chips. All the DIP 68901's I have are all extremely oxidized where the leads enter the chip. Must have been cheaply made even if they have a Motorola logo. Where are the PLCC chips available. I'd like to give one a try.

Its pretty strange when you have boards where all the chips are in good shape except the MFP's.