Monthly Archives: June 2016

Refurbishing a TI PEB power supply

I’ve seen a number of people recommending replacing the older forty-ish watt TI PEB power supply with AT(X) power supplies. As with most stopgaps/workarounds that the TI community has come up with, I’m not sure that’s a good idea. The … Continue reading

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Replace your #$%& console power switch!

If “the solder joints are always bad” is rule #1 when repairing old gear, “the power switch is worn out and must be replaced” is rule #2. The TI-99/4A in-console power supply has a DPDT switch that handles +5VDC and … Continue reading

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Well, it wasn’t the 32k card

I spent an unreasonable amount of time trying to get an in-console expansion working. I’d previously modified my main console with the 16-bit mod, which worked fine, and I thought I’d give Tursi’s scheme a test drive. I wasn’t successful. … Continue reading

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Notes on reworking a low-serial-number HRD into a HRD+

Along with the Horizon 4000 (that I repaired and documented in the previous entry), IM also sent an original HRD. It uses the same board as the HRD+, but had a bit of extra glue logic and was missing the … Continue reading

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