Seiko PS-107 Electronic Starter

The Seiko PS-107 is a discontinued portable electronic starter made by Seiko Time Systems Inc. of Tokyo, the second documented member of the company’s エレクトロニックスタータ line. It replaced the PS-105 and introduced two changes that the rest of the line kept: a second selectable start sound, and a semiconductor relay in place of the earlier mechanical start contact.¹ Like every unit in this line it is general sports equipment rather than swimming-specific. Seiko lists it under multi-timing rather than swimming and publishes no governing-body certification for it, where its poolside PS-1200 generator of the same period was listed as conforming to FINA rules and certified by the Japan Swimming Federation.²³ This article is a starting point; the start-systems overview covers the shared background that applies to every starter.

Models and naming¶

Seiko manufactured the PS-107 from 1997 to 2002.² It replaced the PS-105 and was replaced by the PS-109. The company does not publish a parts-support end date for it; its general policy is that repair and parts supply for a discontinued product run, as a rule, for seven years from the end of production.⁴

The system shipped as the starter pistol PS-77, the headset microphone PS-60, the speaker box PS-50 and a 5 m cable with box, PS-80, with four AA cells, four C cells, the manual and a warranty card.¹ The manual is Japanese only and carries the document number R-I3003.

The headset microphone and the speaker box are carried over unchanged from the PS-105.¹ The pistol is new.

Design and hardware¶

The pistol is moulded ABS in dark grey, 207 W × 153 D × 38 H mm, and weighs about 250 g without batteries or cable. It runs on two lines of two AA cells and its strobe is a xenon lamp.¹ It is dimensionally close to the PS-70 it replaced but not identical, and it is a different unit again from the aluminium pistols Seiko later used on the PS-110.

The speaker box is ABS resin with an aluminium plate, in ivory, 266 W × 92 D × 176 H mm and about 1.5 kg without cells, powered by four C cells at 6 V.¹

The headset microphone is a condenser type of 160 W × 170 D × 68 H mm weighing about 45 g including its cable.¹

Operation¶

The PS-107 offers two start sounds, selected on the pistol’s power switch. At its centre position the unit produces an electronic beep with the strobe flash and the start signal; at the ON position it produces a simulated pistol shot with the same flash and signal.¹ The PS-105 before it had only the one simulated shot.

A separate whistle switch on the speaker box sounds a whistle at a fixed, loud level that the volume control does not affect, which Seiko warns to bear in mind when operating it.¹

Audio¶

The speaker box is rated at 6 W with a maximum of 10 W and a practical sound pressure level of 93 dB at 10 m, with an audio input of -20 dB into 100 kΩ. The pistol takes its microphone input at -50 db, produces the simulated pistol sound at -18 db, and passes microphone audio at up to -5 db at full volume.¹

Seiko states that the speaker box can be used on its own, in multiples, or connected to other equipment, but the manual sets no limit on the number of boxes and gives no maximum total cable length; the supplied cable is 5 m. It does treat cable length as a fault condition, listing a long, high-resistance cable among the causes of a start signal failing to appear.¹ The ten-box and 20 m limits appear only in the later PS-110 manual.⁵

Against manganese cells the manual gives the speaker box about 3,000 pistol sounds, measured until the sound pressure falls below 91 dB at 10 m, and the pistol’s strobe about 480 flashes, counted at one-minute intervals for as long as the ready lamp still takes under a minute to relight.¹

Connections¶

The start signal is a Photo-MOS relay output with an on-resistance of 10 Ω or less, rated for a load of no more than 100 V AC or DC and no more than 0.1 A. It appears between pins 1 and 3 of a Hoshiden TCS0250-01-0301 connector, with TCP0556-01-0201 as the mating cable-side part, and Seiko notes that the signal duration is essentially the same as the duration of the electronic sound.¹

This replaced the make contact of the PS-105, which stayed closed for as long as the trigger was held. The connector part numbers are unchanged between the two.

Specifications¶

Starter pistol (PS-77):

Power	DC 3 V (2 × AA cells) × 2 lines
Strobe	Xenon lamp
Strobe life	Approx. 480 flashes (manganese cells)
Audio battery life	Approx. 125 hours (continuous use at normal temperature)
Start signal	Photo-MOS relay, 10 Ω or less; AC/DC 100 V, 0.1 A maximum
Microphone input	-50 db
Simulated pistol sound	-18 db
Microphone audio at full volume	-5 db
Current draw	Max. 50 mA or less (audio); max. approx. 3 A (strobe)
Enclosure	ABS resin, dark grey
Dimensions	207 W × 153 D × 38 H mm
Weight	Approx. 250 g (excluding cells and cable)
Operating temperature	-10 to +50 °C
Storage temperature	-15 to +60 °C

Speaker box (PS-50):

Power	6 V (4 × C cells)
Current draw	Approx. 3 A on pistol sound; approx. 150 mA silent
Battery life	Approx. 3,000 pistol sounds (manganese cells)
Audio input	-20 dB (100 kΩ)
Rated output	6 W (10 W maximum)
Sound pressure	93 dB at 10 m
Enclosure	ABS resin and aluminium plate, ivory
Dimensions	266 W × 92 D × 176 H mm
Weight	Approx. 1.5 kg (excluding cells)
Operating temperature	-5 to 40 °C
Storage temperature	-15 to 50 °C

Headset microphone (PS-60):

Type	Condenser microphone
Output impedance	1.6 kΩ ±30%
Sensitivity	-68 dB ±3 dB
Dimensions	160 W × 170 D × 68 H mm
Weight	Approx. 45 g (including cable)

The manual makes no statement about weather protection, and names no other Seiko equipment.

See also¶

• Seiko PS-105 Electronic Starter: the predecessor
• Seiko PS-109 Electronic Starter: the successor
• Seiko Electronic Starting System: the current unit in the same line
• Start systems: the start-system overview and governing-body requirements
• Seiko: the manufacturer
• Equipment: the wider equipment reference

References¶

Footnotes¶

1. Seiko Time Systems, エレクトロニックスタータ PS-107 取扱説明書 (document R-I3003, Japanese). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²

2. Seiko Time Creation, discontinued multi-timing products (製造時期 1997年～2002年). ↩ ↩²

3. Internet Archive, Seiko swimming products index, 18 April 2009 snapshot (the PS-1200’s FINA and Japan Swimming Federation certification lines). ↩

4. Seiko Time Creation, discontinued products (repair and parts supply run, as a rule, for seven years from the end of production). ↩

5. Seiko Time Creation, Electronic Starting System PS-110 Operating Manual (the ten-box and 20 m limits). ↩