TEAC FD-55GFR = Quad Density? - test-drb@ccmp.vtda.org

7 Oct 2005

At 19:15 07/10/2005, you wrote:
...
   I found a pair of these drives and picked them up
since my reference said
that they were quad density drives AND they had DS-QD disks in them.
However I looked on the net and found that everyone including Teac's site
says that they are HD (1.2Mb) drives. Which are they? I THINK these have a
jumper that chages the speed from 360 RPM to 300RPM. Will this make the
drive a QD drive? I thought the heads needed to be differnt since the
magnetic media on the disks have different permeability.

    Joe 
One of my favorite FDDs.

These will do either HD or DD (called QD because it is 80 tracks).

The recording density (HD or DD/QD) is defined by interface pin #2.

'LG' strap ON :  Pin2 Hi = DD/QD, Pin2 Low = HD
'LG' strap OFF:  Pin2 Hi = HD, Pin2 Low = DD/QD

You also need to run the drive at 300 RPM in you are using a
standard 250khz transfer rate controller -  To do this, put
strap 'I' ON - this will run at 360 during HD operation, and
300 during DD/QD operation - with 'I' OFF, the drives runs at
360 rpm all the time.

NOTE: A PC controller transfers data to HD drives running in
DD/QD mode at 300khz, which means that PC drives always run at
360rpm - but for a non PC/HD controller, the data rate will be
250khz, and you need to jumper the drive to run at 300rpm.

Dave
-- 
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