Hi Rasz. Thanks for responding. There are a total of four reserved jumpers on the PCB, 2 grouped with the SCSI ID jumpers (JP2), and 2 grouped with the SE jumper (JP1). There is also what looks like solder pads for yet 2 more reserved jumpers (JP3). Perhaps one of these is the ticket to success?
There are some high res. photos of the AEC-7722 with PLCC-32 here,
https://www.ebay.com/itm/332981553745I've attached high-res photos of my AEC-7722IR unit here and edited to my previous post. By comparison of photos on that ebay listing and my unit, I see a few differences.
Capacitors C10, C11, and C13 are located on the top of the PCB for AEC-7722, while on the AEC7722IR, they are on the bottom of the PCB. These 3 caps are the only components on the bottom of the PCB.
On the 7722, C17 is on the top of the PCB, while on 7722IR, there is only a solder pad C17 on the bottom of the PCB.
On the 7722, there exists a resistor R14, which is vacant on the 7722IR unit. It is difficult to say with absolute certainly from the eBay photo, but it looks like it has "158" on it, so 1500 M-ohm. That 8 may be a 0, in which case, 15 ohms.
On the 7722, near JP2, R7, R9, and R10 say "222", so 2.2k. On the 7722IR, rather than individual resistors, there is a 3-pack resistor network (RN1) with "0" on them, so shorted. In the same region, R16 on the 7722 has solder pads for a resistor, while the 7722IR has a 2.2k resistor in the form of another 3-pack resistor network, RN2. R17 is the same on both units, however R13 on the 7722 look to be 300 ohms, while it is 2.2k on the 7722IR (in the form of RN2).
R4 on 7722 has "562" printed on it (5.6k), while on the 7722IR, it is "295", or 2.9 M-ohm.
R15 on the 7722, I cannot read. Perhaps "801" or "103". Maybe somebody with one of these units can verify, but on the 7722IR, the resistor says "0", so shorted.
I can probably make all these changes, but would need clarification on R14 and R15.
So what do you think the next best course of action is? Is there a better, perhaps more diagnostic method, to determine the PCB mod required for using the PLCC-32?