Citizen CQ 4-730020TA: Crystron-Era Quartz, Smoky Green Dial, Near NOS
A Citizen CQ 4-730020TA is a late-1970s Japan-market quartz day-date: angular steel case, smoky green dial, original bracelet. This one is close to NOS. The edges are still sharp. The dial has not faded. The bracelet matches the case. It has just been serviced.
What CQ meant
Seiko shipped the Astron, the first quartz wristwatch, in December 1969. Citizen did not answer with a copy. It answered with Crystron. The analog Crystron reached the market in the early 1970s — official step-motor models from 1974, rated about ±15 seconds a month, with a seconds-stop and, on some, a small LED at 12. Before that, Citizen’s Cosmotron was still a hybrid: a quartz timer driving a mechanical balance. Crystron dropped the balance.
CQ is Citizen Quartz. By the late 1970s the Crystron name was being folded into CQ on watches people actually bought: steel cases, day-date, water-resist marks, a price above a mechanical Seiko 5 because the technology was still the point. The laboratory piece was the 1975 Crystron Mega, ±3 seconds a year, crystal at 4.19 MHz, priced like a car. This 4-730020TA is not that watch. It is the wearable CQ: Caliber 7300 family, two-jewel quartz, day and date, 10 atm on the dial.
This 4-730020TA
Round-square steel, about 35 mm, 18 mm lugs, brushed top, polished bevels. The edges have not been rolled. That is the condition note that matters on a 1970s integrated-style case. The dial is a smoky gradient green — darker at the rim, lighter through the centre — with applied batons and a kanji day beside the date at 3. Water Resist 10 atm is the factory mark. At this age, treat it as a dress-sport watch, not a diver.
The original Citizen bracelet is in the same state as the case: links tight, brush still there, no stretch. Movement just serviced. Battery timekeeping, not a high-beat tick.
Specification
Maker: Citizen
Model: CQ 4-730020TA (Citizen Quartz)
Era: around 1977
Case: Stainless, angular, edges still sharp, close to NOS
Case Diameter: approx. 35 mm
Lug Width: 18 mm
Dial: Smoky gradient green, applied batons, kanji day and date at 3, 10 atm mark
Bracelet: Original Citizen, excellent
Movement: Quartz Caliber 7300 family, just serviced
A vintage Citizen CQ 4-730020TA in this state is the late-1970s quartz Citizen people skip while hunting Crystron Mega. Same decade, wearable size, green dial that still looks new, bracelet that still belongs to the case.
