Sounds of the PTI PT-357R

Рет қаралды 216

29 күн бұрын

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Peripheral Technology Inc. PT-357R
Country of Origin: Taiwan(?)
Introduced: Q4 1990(?)
Interface: ST-412HP (RLL2,7 nominal)
Capacity: 46MB
Form: 3.5 HH (1")
CHS: 612 / 6 / 26
LZN: 613
WPC: 65535
Track-track: 10.9ms
Linear access: 26.3ms
Random access: 39.7ms
Rotational: 3600RPM
Media: Semimetallic, offset TF heads
Disks: 3
Actuation: Rack and pinion brushless DC servo motor
Feedback: Optical servo encoder + On-surface pulses
Lift/Lock/Park: Automatic parking, shipping lock solenoid
Brake: Dynamic
Service life: 5 years / 25,000 hours
Related models: PT-225 (2 disk, MFM); PT-338 (MFM); PT-238R (2 disk); PT-357A (ATA); PT-357S (SCSI-1)
Failures: The actuator rack is driven directly by the shaft of the actuator motor using a spline rather than a proper gear mesh. Due to conditions such as a stiff rail, faulty solenoid lock, or misalignment, this may cause the pinion to grind against the rack and chip or damage it, as well as the pinion. This also causes the optical encoder to be out of alignment and can cause the drive to fail it's seek test.
Settings: aioinc.ddns.net/HOST/TH99/h/tx...
My thoughts:
This drive is a strange one. It appears as a cross between a Tandon TM-262 and a Microscience HH-325 almost, having the pigtail power connector and angled actuator motor of the HH-325 with the gold colored lid and L-clip retainers of the TM-262. The scarcity of these drives and information on them implies that they were either very unpopular or very unreliable, and through my experience with this unit, I am inclined to believe the latter. This drive came to me nonfunctional with no less than 4 "Warranty Void" seals on the lid, implying that the drive was probably sent to be repaired at least 3 times during it's warranty period before it was retired. It is incredibly temperature sensitive and will fail a seek test below 65*F. It appears that the drive is designed to have an automatic parking feature during power off, but mine does not seem to work. This drive has many problems, and I'm not entirely sure if they're mechanical or electronic in nature.

Пікірлер: 10

@bobjoe2827 27 күн бұрын

These drives are more like a cross between a CMI CM-6426S and a MiniScribe 8425 in that they use an optical encoder with wedge servo (like the CM-6426S) and a rack and pinion setup almost identical to the 8425. I read that PTI got sued by quantum (for the same reason as CMI) and had to discontinue making these drives, which would explain their scarcity. It goes without saying that these drives are a pain in the rear to realign if the encoder gets out of sync with the actuator carriage (I used a dual channel oscilloscope, one channel for the encoder, one for the servo pulse).

@TheDiskMaster 26 күн бұрын

@@bobjoe2827 interesting, I did not know CMI was sued by Quantum. For what it's worth, CMI did not have wedge servo, they just had centering pulses and an embedded track 0. The comparison I made was more for the visual appearance of the drive than anything else.

@bobjoe2827 26 күн бұрын

@@TheDiskMaster I'll have to see if I can find the article on PTI, Quantum was the RCA of their day and sued many smaller companies over patent disputes. That is true about the appearance being similar to the Tandon and Microscience drives, that makes these drives a mix of the least reliable hard drives ever made (excluding Kalok).

@pc4ad 27 күн бұрын

I wonder if an low-level format would 'repair' this drive as it does seem to have some issues.

@TheDiskMaster 27 күн бұрын

@@pc4ad No, this is after several low level formats. It makes no difference.

@NikolaiKostadinov-dc7jq 28 күн бұрын

Isn't that just a tandon TM-262? I remember that western digital sold them under their name too.

@Kali_Krause 28 күн бұрын

It's a cross between a Tandon TM-262 and a Microscience HH-325

@TheDiskMaster 28 күн бұрын

@@NikolaiKostadinov-dc7jq No. The Tandon TM-262 is a stepper based 20MB drive. This is optical servo, 40MB, rated for RLL code, has on-disk feedback, has a totally different chassis, and much lower power requirements. It's performance is also vastly better. You can watch a video on my Tandon TM-362 if you want a direct comparison of how dissimilar these two drives are.

@TheDiskMaster 28 күн бұрын

@@Kali_Krause Except all the things I just listed above