Monotech

Vintage computer enthusiast. Designer of new parts for vintage PCs. Here you will find my vintage PC adventures, and news/details about my products!

[Monotech @MonotechPCs]

@carlogmas Yes. New stock should be ready in April or May.

[Monotech @MonotechPCs]

New product! This is replacing both the XT-IDE and XT-CF in the store.

XT-IDE Deluxe!
Bootable ISA IDE+CF interface, with greater speed and compatibility than XT-CF.

Use IDE, CF, or both! Up to 2 drives max.
Supports IBM XT Slot-8.

Purchase here:
https://t.co/3Ykiyi6lzk

[Monotech @MonotechPCs]

@RTLV_Design Yea JLC is great. Something new every month.

[Monotech @MonotechPCs]

8-layer PCBs for $2. What a time :D

[Monotech @MonotechPCs]

@JunkSmithWizard Nope. It doesn't connect to an IDE host - it connects to ISA.

[Monotech @MonotechPCs]

@JunkSmithWizard Could be. Or something similar

[Monotech @MonotechPCs]

@lukas_jele Ohh very interesting. So they may be Synertek 6502s originally.

[Monotech @MonotechPCs]

They really cranked the laser up to 11 when re-marking these 6502s.
6 out of 10 work.
The bottom sides seem untouched (faulty on left, working on right).

[Monotech @MonotechPCs]

@RetroXTPC Don't use the XT-IDE BIOS added onto the image after assembling 0.9.8. It's old and not configured for the XT-CF interface on the Nano 8088.
Get the latest XTIDECFG and IDE_XTL.BIN (or IDE-XTPL.BIN for higher speed with V20 CPU).
Then combine them in a hex editor - new 128K image

[Monotech @MonotechPCs]

@TubeTimeUS Your PSU board looks different to one I fixed. A common fault in the type I fixed at least, are some small electrolytics (1uF etc).

The 5154 I fixed had all kinds of problems due to a bad tripler. I managed to find some replacements and have spares if needed.

[Monotech @MonotechPCs]

@RetroXTPC Could you elaborate on your last question?

[Monotech @MonotechPCs]

@RetroXTPC U17 (the chip you marked "A") is 512-640K region and UMB. Try replacing that. Where did you purchase the chips from? If from a proper distributor, they shouldn't be faulty.

[Monotech @MonotechPCs]

@RetroXTPC You're welcome ^^
Also, the fact it counts to 528K, means the first 16K of the second chip works.
I suspect a soldering issue on the second RAM chip.

[Monotech @MonotechPCs]

@sommteck Excellent :D
That's an old-style CGA too - the most desirable.
You should set the video card type to 80-column CGA on the System Config DIP switch.

[Monotech @MonotechPCs]

@WysWyg_Protogen There's a lot of conflicting anecdote about ALS120 online.
ALS100+ seems to be better than ALS100 and ALS120, but ALS120 seems to not be a bad chip.
ALS100+ apparently has an exact OPL3 clone inside.
Maybe see if PhilsComputerLab has covered it - they have good soundcard tests.

[Monotech @MonotechPCs]

@marcoteixeira This was an eBay find, so you'll just need to save a search of keep a lookout.

[Monotech @MonotechPCs]

New in box IBM 5140 power supply.
I smelled the smell of cat pee as I closed the cardboard box after pulling it out.
The smell is so bad up close.
It's gonna be full of leaking caps :'D

[Monotech @MonotechPCs]

Some more results. Someone kindly provided a BASIC program that works on Commodore machines and Apple II. I ran it on a PET 2001, and discovered some of my samples are 65C02, which I suspected as they crash on C64 demos (when in my MOS CPU Replacer).

[Monotech @MonotechPCs]

@JafirElkurd Other caps are fine, but I replaced them except for the main input (150uF 400V).
The source of the smell was indeed that one leaking cap.
Powered it up. It works :D

Yea I could use any 12V wall adapter, but all mine are 2A, which is enough for the 5140, but add-ons pushing it...

[Monotech @MonotechPCs]

@JafirElkurd This cap on the secondary side had leaked. The PCB core seems to have reacted slightly.
Will check the other caps after removing some of the conformal coating.