Miracle Systems Floppy PSU

[bagpuss22]

They seem to be 5v only, that is all it states on the label.

I have another question about them. I have never used floppies on my QL before.

I have powered them tonight using an external PC supply and FLP1_ seems to work ok, reads, writes and formats well. FLP2_ seems to be intermittent on loading but will not save or format!? When you save it says read only and format fails.

I swappped the drives over but it seems that FLP2_ stays as FLP2_. I am assuming they have a jumper on them that states their a setting??

Could do with some info on how these are setup and used really..

Thanks

Russ

[belg4rion67]

Hi, in another thread of Hardware place there are some info useful for your issue; Rich (rwap) explain very fine what you need to check in cable, in floppy drive or both... if I well remember in old fdd there are some jumps to choose if a drive is ds0 or ds1 (same as A: or B: in Dos).
I have two modern fdd units and I'm using a straight cable to connect both drive but for first drive (flp1_) wires 10 and 12 are switched.
cheers
paolo

[RWAP]

The drives Miracle used tended to have a jumper to choose between DS0 (flp1_ ) and DS1 (flp2_).

The chances are that the head has been damaged on the second drive

Although you can luckily use any modern PC floppy disk drive as flp2_ (as they are set up as DS1), the problems can be finding a drive with the power and floppy cable on the same side as flp1_, plus finding one with a black bezel...

As far as I know, most PC floppy disk drives work on just 5V - although I have come across ones which have a 12V lead as well (!) and some where even the wires went to different pins - before trying to make up sets of dual disk drives, I had thought that there was pretty much standardisation in PC floppy disk drives - how wrong can you be?

I do have some spare floppy disk drives here - they all need testing (quite a few seem to be failing), so I need to know which side is the power connector and floppy cable to see if I have a matching one!

[1024MAK]

NEC FD1037A Floppy Disk Drives

Here are some pictures found as a result of a internet search.
The first one clearly shows that it uses +5V and +12V
The rest all look like single +5V supply types.



Mark

[Dave]

NEC and Citizen mechanisms that listed 12v could "some times" still run off a single 5v supply if the current was available. The 12v was usually rectified down to 5v to run the motor anyway. On these devices, on just 5v supplies, sometimes when the motor started the electronics would trip up.

Those were fun times.

[bagpuss22]

New Power Supply has arrived, Thanks Rich.

Will get this installed tonight and see where we are!

Maybe have a game of Psion Chess too !

Russ