Quick answer. Check the complete link before buying a longer-reach converter. Distance, endpoint compatibility and received power are separate checks. If the exact SKU optical limits are missing, compatibility remains unconfirmed.
1. What the 20 km reference means
The KG-FMC-1G-BD-SC-20-KIT page describes two complementary Gigabit A+B converters, one single-mode fiber and SC ports. Its reach is stated as up to 20 km, subject to the optical budget and link condition. Fiber cable is not included.
The page reviewed does not publish minimum/maximum TX power, RX sensitivity or the overload limit. It also does not specify the SC polish here. Request these details for the exact reference; do not borrow them from another model or infer them from a dust-cap color.
2. Open a checklist for each endpoint
To avoid unnecessary replacements, record the symptom: no power, no optical link, no Ethernet link or intermittent traffic. Note when it happens and what changed. Keep photographs of the A/B labels and an inventory of the installed cabling.
| Information | Endpoint A | Endpoint B |
|---|---|---|
| SKU and revision | Copy label | Copy label |
| TX/RX and wavelength | Request exact datasheet | Request exact datasheet |
| Fiber, connector and polish | Confirm interface | Confirm interface |
| Power and Ethernet | Record equipment and state | Record equipment and state |
3. Compare optical budget and loss
FOA distinguishes equipment optical capability from cabling loss. For an initial estimate, subtract RX sensitivity from minimum TX power and reserve a margin. Include fiber, connection and splice losses. Check the remaining system limits too.
Hypothetical example, not a KONGIA specification or test: minimum TX of −8 dBm and RX sensitivity of −20 dBm give 12 dB. A chosen 3 dB margin leaves 9 dB for loss. A measured 10 dB loss would fail this criterion even below 20 km. That margin is an assumption for this example, not a universal rule.
4. More power is not always helpful
FOA explains that a receiver has both lower and upper power limits. A short link can also deliver too much signal. Checking the upper limit uses maximum TX power and the lowest expected loss, separately from the weak-signal case.
Do not add an attenuator by guesswork. Request receiver limits and an appropriate measurement. For BiDi, check both directions and their wavelengths; one reading does not validate the complete pair.
5. Prepare a useful technical review
Before requesting replacement products, collect one record per link. The installation lead should check connectors and loss with suitable instruments; an illuminated LED is not an acceptance report.
- Identify both devices, their A/B labels and their power adapters.
- Draw the route and list panels, splices and patch cords.
- Confirm fiber, connector and polish before connecting.
- Attach loss/power results with wavelength, direction and method.
- Include delivery city in Chile, quantity and urgency if requesting a quotation.
Related KONGIA products
Questions before ordering
Will buying the 40 km version solve the problem?
That cannot be concluded without diagnosis. First establish whether compatibility, power, cabling or optical level is responsible.
Can the exact margin of this kit be calculated from the page?
Not from the public information reviewed. TX/RX limits are missing and should be requested before approving a design.
Is 12 dB a KONGIA product value?
No. It is a hypothetical calculation to explain subtraction and margin, not a specification for any SKU.
Sources and scope
Preparation for troubleshooting, not a test report. The KONGIA page supports only the cited product characteristics; FOA supports the optical principles. No external reference certifies this product.
- KONGIA — KG-FMC-1G-BD-SC-20-KIT
- FOA — Power budgets and loss budgets
- FOA — Receiver operating range and attenuators
This guide was prepared with AI assistance using the listed product information and references. It is not an independent test report. Specifications and availability must be confirmed for the exact SKU and project. Editorial policy