Mike's PCjr Page

I recently picked up a PCjr that has a Quadram expansion unit that mounts on the top and adds a second disc drive and more ram thou I don't know how much. it has it's own psu board inside and a separate power connector so I'm guessing it needs it's own power brick. Does anyone have any information they could pass on?

I believe those are essentially the same as the Rapport units. They use the same type of brick as the PCjr itself.

Yep - Rapport == Racore == Quadram. All of those expansion chassis are the same maker.

I think that Rapport changed their name or was bought by Racore. Quadram just licensed the design to fill out their product line. They included different, but equivalent software. The hardware is the same as the corresponding Racore unit.

If you do a atx psu conversion would it be hard to run both units from the some power supply

I have another question. I finally got a power brick in so I could actually test the unit. since I only have the one I unhooked the quadram for now. I'm using the composite out and the screen is very distorted and grainy. is this likely a issue with the pc or the rf modulator.

It is hard to tell if you have a problem without a picture ...

If you are using the composite out then there is no RF modulator in the loop. The RF modulator is in the external adapter that plugs into the dedicated "TV" port on the back. The composite output should look reasonable in 40 column mode; the color bars on the initial screen should be reasonably good looking. In 80 column mode with color enabled it will be hard, but not impossible to read. 80 column B&W mode is much easier on the eyes.

correction I'm using the RF

Legacy is an entirely different design.

Brutman wrote:Yep - Rapport == Racore == Quadram. All of those expansion chassis are the same maker.

I think that Rapport changed their name or was bought by Racore. Quadram just licensed the design to fill out their product line. They included different, but equivalent software. The hardware is the same as the corresponding Racore unit.

I dont think I have seen a Quadram unit that comes with 512k memory expansion... all the ones I have seen are the 384k memory expansion units.

The early Rapport/Racore units also had the 384k memory expansions but the later ones were mostly 512k memory expansions.

I have 2 Racore units one with the 384k board and one with the 512k board. If the memory board has 6 banks for chips ( 2 banks filled with soldered in chips and 4 banks of socketed chips ) in it then its the 384k board, if its the one that has 2 banks for chips ( 1 bank filled with soldered in chips and 1 banks of socketed chips ) then its the 512k board