---
description: Genuine Ronda 775/785 coil block, Swiss made. Core stepper drive for 775 (7¾ ligne) and 785 (8¾ ligne), resistance 1.8-2.6kΩ, fits 362/364 battery.
title: Ronda 775/785 Coil Block - Sofly
image: https://www.soflypart.com/wp-content/uploads/2019/05/785CO.jpg
---
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- **Ronda 775/785 Coil Block**
[](https://www.soflypart.com/wp-content/uploads/2019/05/785CO.jpg)
[](https://www.soflypart.com/wp-content/uploads/2019/05/785COB.jpg)
# Ronda 775/785 Coil Block
$3.00
You Saved
| Brand | Choose an option Ronda- 
Clear |
| --- | --- |
### Discount
| Quantity | Discount (%) | Price |
| --- | --- | --- |
| 1 - 4 | — | $3.00 |
| 5 - 9 | 5% | $2.85 |
| 10+ | 10% | $2.70 |
### Discount
| Quantity | Discount (%) | Price |
| --- | --- | --- |
| 1 - 4 | — | $3.00 |
| 5 - 9 | 5% | $2.85 |
| 10+ | 10% | $2.70 |
Ronda 775/785 Coil Block quantity
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## Product Description
This is a **genuine Ronda coil block** for **775/785 movements**, a **Swiss-made** component. It serves as the **core electromagnetic component** of the circuit assembly, precisely converting electronic pulses from the IC into magnetic energy to drive the stepper motor rotor and gear train. This product is **brand new and original**, designed for movements where the original coil has failed due to moisture ingress, battery leakage, corrosion, or mechanical damage.
## Specifications
- **Brand**：Ronda (Swiss)
- **Compatible Movements**：**775 series** / **785 series** (Normtech line)
- **Origin**：**Swiss Made**
- **Quality**：**Genuine original**, brand new
- **Function**：**Converts electronic pulses to magnetic energy** for stepper motor
## FAQ
**1. Is this coil block an original Ronda genuine part?**
**Yes**. It is an **original Ronda factory part** from Switzerland, designed for 775 and 785 Normtech series movements.
**2. Are the 775 and 785 coils interchangeable?**
**No**. Although both belong to the Normtech family, the 775 is **7¾ ligne** (approx. 17.2mm) while the 785 is **8¾ ligne** (approx. 20.0mm)—their sizes and stator configurations differ, and the coils are **not compatible**.
**3. How do I check if the coil is faulty?**
Use a multimeter (resistance mode) to measure between the two coil contacts. Normal reading: **1.8–2.6 kΩ**. An “OL” reading (open circuit) or very low resistance (short circuit) indicates a faulty coil.
## Why Choose SOFLY Watch Parts?
**Fast Worldwide Shipping** – Orders are dispatched within 3 business days.
**Competitive Pricing** – Great value across watch movements, replacement parts and watchmaking tools.
**Extensive Selection** – More than 3,000 watch movements, parts and accessories available.
**Trusted Worldwide** – Trusted by watchmakers, repair professionals and watch enthusiasts worldwide.
**Personalized Sourcing** – Can’t find the part you need? Contact **info@soflypart.com** or WhatsApp **+86 18620212114.**
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It serves as the\u00a0core electromagnetic component\u00a0of the circuit assembly, precisely converting electronic pulses from the IC into magnetic energy to drive the stepper motor rotor and gear train. This product is\u00a0brand new and original, designed for movements where the original coil has failed due to moisture ingress, battery leakage, corrosion, or mechanical damage. Specifications Brand\uff1aRonda (Swiss) Compatible Movements\uff1a775 series\u00a0/\u00a0785 series\u00a0(Normtech line) Origin\uff1aSwiss Made Quality\uff1aGenuine original, brand new Function\uff1aConverts electronic pulses to magnetic energy\u00a0for stepper motor FAQ 1. Is this coil block an original Ronda genuine part? Yes. It is an\u00a0original Ronda factory part\u00a0from Switzerland, designed for 775 and 785 Normtech series movements.\u00a0 2. Are the 775 and 785 coils interchangeable? 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Personalized Sourcing\u00a0\u2013 Can\u2019t find the part you need? Contact\u00a0info@soflypart.com\u00a0or WhatsApp\u00a0+86 18620212114.","image":"https://www.soflypart.com/wp-content/uploads/2019/05/785CO-150x150.jpg","offers":{"@type":"Offer","description":"Product Description This is a\u00a0genuine Ronda coil block\u00a0for\u00a0775/785 movements, a\u00a0Swiss-made\u00a0component. It serves as the\u00a0core electromagnetic component\u00a0of the circuit assembly, precisely converting electronic pulses from the IC into magnetic energy to drive the stepper motor rotor and gear train. This product is\u00a0brand new and original, designed for movements where the original coil has failed due to moisture ingress, battery leakage, corrosion, or mechanical damage. 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