modem7's latest activity

As one possibility, be aware of the 'Deteriorated lubrication' section of [here]. Sometimes, the problem will be that the 'system' that...

Let's just hope that your motherboard is not intermittent. If you are back to the original symptom of 'not recognising more than 256 KB...

I have released a new version of Ruud's Diagnostic ROM. It is now at version 4.8 Available at minuszerodegrees.net Bug fix #1 Version...

Thank you. I updated the Acculogic sIDE-1 entry at [here]. ( A page refresh in your browser may be required. )

Power is good, and we have a good idea of what equipment you have to aid diagnosis. I forgot that you had mentioned the POST card...

There is one way that will definitely work, assuming fully functional hardware: Step 1: Get yourself a DOS boot floppy/diskette...

Which hints to me your level of soldering skill. An incorrect failure address of 5040 being reported by the SLDR is known of...

To my astonishment, I experienced what you do. SLDR with IBM MDA = Works RDR with IBM MDA = Something wrong during checkpoint 0...

My soldering technique varies according to the job, but for dual-in-line IC's, I use the technique shown at [here].

Thank you. I added that 'KW-530 Series' manual to the Kouwei section of [here]. ( A page refresh in your browser may be required. )

I brought out a 5150 motherboard of type 16KB-64KB. I plugged in an IBM MDA card, and PSU. I attached a speaker. I put in the SLDR...

Some kind of 5150 motherboard problem is also a possibility. I trust you. Back at post #9, in regard to the use of the SLDR, you...

Both SLDR and RDR display characters on screen by writing bytes directly to video RAM. For example, on an MDA card, to put a '3' in the...

I have seen that behaviour myself. With no U28 in place, when a read of a motherboard address corresponding to U28 is done, there is...

These are resistor networks ('RN'). Only sometimes are resistor networks used in a termination role. Looking at the circuit diagram of...