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JST-GH

The GH is the smallest connector most hobbyists will ever like: a 1.25 mm-pitch wire-to-board family whose defining feature is a positive latch with an audible click — on a connector barely wider than a grain of rice. That latch is why the drone world standardized on it, and the standardization is why "GH" is one of the few small-connector names a marketplace listing might actually mean.

What people call it​

GH, "Pixhawk connector," "drone cable," "JST 1.25" (dangerously incomplete — see the lookalikes below), GHR (the housing part-number prefix).

What it actually is​

The genuine JST GH series: 1.25 mm pitch, wire-to-board, 2–15 circuits, with a locking housing that clicks over the header shroud. Rated 1 A (AWG #26) and 50 V, wire range AWG #30–26, per the official JST datasheet1 — a signal-class family: sensors, GPS, telemetry, CAN, I2C, UART, not power runs. Housings are GHR-xxV-S; contacts and shrouded (typically surface-mount) headers are GH-specific line items.

Why drones standardized on it​

The Pixhawk Connector Standard (DS-009) — the interface standard behind the Pixhawk/PX4/ArduPilot flight-controller ecosystem — specifies the JST GH series as its connector, defining standard ports (GPS, telemetry, CAN, power and so on) around it.2 That decision is a compact case study in connector selection:

  • The predecessor was a friction fit. Earlier Pixhawk-era boards used 1.25 mm Hirose DF13 headers — small, but with no positive latch. On machines that are one unplugged GPS lead away from a flyaway, friction retention was the wrong bet, and the ecosystem moved to the latched GH.2
  • A latch you can hear. The GH's click is a verifiable assembly state on a connector too small to inspect visually in a crowded frame.
  • Standard ports, standard cables. Because DS-009 defines port pinouts, off-the-shelf GH cables interconnect gear from different vendors — the whole point of a connector standard rather than merely a connector.

The honest caveat carried by the standard's own ecosystem: not every board with GH connectors follows DS-009 pinouts. Verify the flight controller's documentation before trusting a cable that "fits" — fitting was never the question.2

How to identify it — the 1-point-something lookalikes​

Measure the pitch, then find the latch. The small-pitch crowd is where "looks right" fails hardest:

FamilyPitchRetentionThe tell
JST SH1.0 mmfrictionsmaller than GH; no latch arm — the Qwiic/STEMMA QT connector
JST GH1.25 mmpositive latchthe fold-over latch arm on the housing top, and the click
Molex PicoBlade-style1.25 mmfrictionsame pitch as GH, different family — no latch, different housing/contact geometry
JST ZH1.5 mmfrictionthe next size up; see JST Is Not One Connector

The PicoBlade row is the expensive one: pitch match is not family match. "JST 1.25" and "PicoBlade" listings are routinely mixed in drone-cable storefronts, the two do not intermate, and a forced mismatch on a flight controller is a bad day with a serial number. Match the family by drawing, not by measuring alone.

Line diagram comparing SH, GH, and PicoBlade-style housings, with the GH latch arm highlighted and pitch callouts

The lineup that causes the trouble: SH is smaller, PicoBlade is the same size — the GH's latch arm is the tell.

What to buy​

  • Pre-crimped GH leads first. GH contacts are in the same tiny-terminal class as SH — the pre-crimped-leads rule applies at full strength, and DS-009-pinout cable sets are a standard drone-shop item.
  • Housings (GHR-xxV-S), GH contacts, and headers are separate, GH-specific line items from authorized distributors — the mating-parts rules apply, and nothing from the kit drawer substitutes.
  • Marketplace "Pixhawk cables" get the standard listing skepticism: verify family and pinout, because a correct connector wired in a vendor-specific order is the sneakiest failure in the ecosystem.

Common traps​

  • A fitting cable with the wrong pinout. The GH standardization makes cables interchangeable only where boards actually follow DS-009 — check the manual's pinout table, every time.2
  • Power through a signal family. 1 A at AWG #26 is the datasheet ceiling1 — motor power, servo rails, and high-current video gear belong on power connectors (XT-class and friends), with GH carrying the data.
  • Confusing it with SH or PicoBlade — the table above; the latch arm is the tell.
  • Wire fatigue at the housing. The latch holds, so #30–26 wire takes the vibration instead — strain-relieve harness runs on anything that flies, and tug-test crimped leads before they're zip-tied in.

When to move to the engineering track​

GH is genuinely good — latched, specified, standardized — which makes it the hobby track's best demonstration of why those properties matter. When the environment adds sealing, field service, or crash-level abuse, the same logic scales up: When Hobby Connectors Are Not Enough, then the engineering track's internal PCB harnessing path for the latched-family menu one weight class up.

Source status​

Pitch, circuit span, latch, and the 1 A / 50 V / AWG #30–26 figures are sourced to the official JST GH datasheet;1 the Pixhawk standardization on GH, the DS-009 port framework, and the DF13-predecessor history to the Pixhawk standards document and the Dronecode connector-workgroup documentation.2 Genuine-part figures only — "GH-style" and "Pixhawk cable" marketplace parts inherit nothing. PicoBlade-distinction guidance is identification-level. Tracked in Hobby Source Notes.

Sources​

Footnotes​

  1. JST GH series datasheet, official JST PDF — 1.25 mm pitch, wire-to-board with a positive outer latch; 2–15 circuits; 1.0 A AC/DC (AWG #26), 50 V, wire range AWG #30–26. https://www.jst-mfg.com/product/pdf/eng/eGH.pdf ↩ ↩2 ↩3

  2. Pixhawk Standards, DS-009 Pixhawk Connector Standard — the Pixhawk ecosystem's connector standard, specifying the JST GH series and standard port definitions. https://github.com/pixhawk/Pixhawk-Standards/blob/master/DS-009%20Pixhawk%20Connector%20Standard.pdf; Dronecode connector-workgroup documentation — GH's latch-lock-at-small-size rationale, the earlier DF13-based boards it replaced, and the caveat that GH-equipped boards do not all follow the standard's pinouts. https://wiki.dronecode.org/workgroup/connectors/start ↩ ↩2 ↩3 ↩4 ↩5