Modified HP-71B MultiMOD Issue

[BitWiz]

I recently acquired an JHP-71B (1BBB) that has had the 4 internal 4K memory chips replaced with 4 32K memory board. In addition the CPU has been sped up to 886KHz.

This is causing the MultiMOD to not work.

1. Are there any internal registers in the 71 that can slow down the bus so that the MultiMOD will work?

2. Short of removing the clock speed up, is there anyway to get the MultiMOD to work at this speed?

3. If there is no way to get the MultiMOD to work are there any other RAM/ROM emulators available for the 71B that are still in production?

I specifically would like to have the HP-41 Translator ROM and Forth/Assembler ROMs in my unit.

4. Does anyone have either these modules for sale or some kind of ROM emulation they are looking for a good home for.

And Last but not least the background of the LCD is spotted and dark. The LCD is fine and clear. Is there any way to clean that without moving all of the heat stakes and separating the keyboard board from the case front?

Pictures of the inside can be found here: https://www.facebook.com/photo/?fbid=937...1359683085

Thank you all,

Mike.

I am looking to buy/trade for (preferably at below ePay prices)

82161A Digital Cassette Drive
Any HP-IL Video Interface
9114B 3.5" Floppy Disk Drive
HP-IL Serial Interface
Any HP LED calculator
Any PDP-8 equipment, boards or peripherals

I am building 3D printed battery packs with fresh batteries for the Classic (82001), Woodstock (82019) and Topcat (82033) series machines. Please contact me directly if you are interested in purchasing any. Selling at below ePay prices. I also have a bunch of Mini Data Cassettes for sale or trade.