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TEAC FD-55 GFV

The TEAC FD-55 GFV has a notably different PCB from its other variants, and does not include the same cross shaped drive speed jumper as literally all of its other iterations. It appears to be targeted as a drop-in replacement for 8“ disk drives.

Specifications

8” disks typically had 77 tracks, while high-density 5.25“ disks had 80 tracks. Because this drive is meant to be a replacement for an 8” drive, the original spec sheet shows the data for both 80-track disks and 77-track disks for FM and MFM write modes. For simplicity, this table shows the data for 80 tracks and assumes that MFM is always used.

Capacity Formatted: HD 1.2 MiB; DD 655.36 KiB
Unformatted: HD 1.6 MiB; DD 1.0 MiB
Disk size 5.25“
Heads 2
Surfaces 2
Tracks/Surface 77 / 80
Track density 96 tpi (tracks/in)
Bit density HD: 9870 bpi; DD: 5922 bpi
Record method FM / MFM
Rotation rate HD: 360 rpm; DD: 300/360 rpm
Seek time Track to track: 3 ms
Settle time 15 ms
Data transfer HD: 500 Kib/s; DD: 250 / 300 Kib/s
Power +5 V, +12 V
Power dissipation 5.2 watts operating, 1.8 W at rest

Physical specs:

Height 1.63 in / 41.3 mm
Width 5.75 in / 146 mm
Depth 7.99 in / 203 mm
Weight 1.2 kg nominal, 1.35 kg maximum
Shock rating Operating: <10 G;
Non-operating: <40 G
Vibration Operating: <0.5 G @ < 55 Hz, <0.25 G @ 55 - 500 Hz;
Non-operating <2 G @ 0 - 100 Hz

(Specifications come from z1013.mrboot.de and have been translated from German.)

Jumper Settings

The following jumper settings are known to work with the Applesauce:

DCRY RY Disk Change/Ready on line 34*
DS0 Connected Drive select (any drive number is fine)
DS1 Not connected
DS2 Not connected
DS3 Not connected
U1 Not connected Head load on motor on
U2 Connected
HL Not connected Pin 4 is Head Load
IU Not connected Pin 4 is In Use
LG-HG HG (both!) Sets High Density input level

* ⚠️ Make a note of the original setting if you change the DCRY jumper! See DISK CHANGE/READY for a more thorough explanation.