RF video overlay is not a legacy artefact in FTTH networks — it is still the cheapest way to deliver linear TV to a large installed base of set-top boxes. In a PON network, that overlay travels at 1550 nm, sharing the fiber with 1490 nm downstream data and 1310 nm upstream.
The optical receiver at the subscriber end — or at the MDU riser — decides whether that overlay survives the trip. This guide covers the six points that determine a working deployment, and the compliance items that decide whether the unit can legally be installed in Europe or North America at all.
1. Start With the Wavelength Plan, Not the Receiver
Before comparing receivers, confirm the wavelength plan of the PON you are overlaying:
| Signal | Wavelength | Direction |
|---|---|---|
| PON downstream data | 1490 nm | OLT → ONT |
| PON upstream data | 1310 nm | ONT → OLT |
| RF video overlay | 1550 nm | OLT → subscriber |
| Optional RF return (RFoG) | 1310 nm or 1610 nm | subscriber → OLT |
The receiver must isolate 1550 nm from the 1490 nm data channel with enough rejection that the data signal does not leak into the RF output as in-band interference. Ask for the WDM filter isolation figure in dB — a receiver that only quotes "1550 nm" without a filter profile is a receiver you cannot design with.
2. Input Optical Power Range and AGC
RF overlay power budgets vary widely: an MDU riser may deliver −2 dBm while a long feeder might arrive at −10 dBm.
- Without AGC, RF output level falls directly with optical input — your subscribers at the end of the line get a weaker signal.
- With AGC, the receiver holds RF output constant across a defined optical input window (commonly −8 to 0 dBm).
For any deployment with mixed fiber lengths, specify AGC. It is the single feature that most reduces field service calls.
Also confirm the maximum input power before saturation — critical when a receiver sits close to the OLT.
3. RF Bandwidth and Output Level
Match bandwidth to what you actually carry:
- 47–1000 MHz — standard DVB-C / DOCSIS-enabled plant
- 47–1218 MHz — required if the network is being upgraded to 1.2 GHz
- Return path (5–65 MHz) — only if you need RFoG return
Output level should be quoted at a stated optical input power and OMI. A figure like "≥ 100 dBµV" is meaningless without those two conditions.
4. Noise and Distortion: Demand the Test Conditions
CNR, CSO and CTB are the numbers your network engineers will ask for. Insist on:
- Number of loaded channels
- Optical modulation index (OMI) used
- Optical input power at test
- Link loss
Comparative grading is only possible when both vendors tested under the same conditions.
5. Physical Form Factor — Where It Will Actually Live
| Deployment | Requirement |
|---|---|
| Single-family ONT wall box | Compact, wall-mount, low power consumption, no fan |
| MDU / riser cabinet | DIN-rail or rack tray, wider temperature range |
| Outdoor enclosure (EU winter / US South summer) | Extended temperature range, conformal-coated PCB |
For Northern European outdoor cabinets and North American southern-tier enclosures, the operating temperature range and humidity tolerance are the two specs that most often cause premature failure.
6. Compliance — The Gate You Cannot Walk Around
This is the part that most often removes a supplier from the shortlist.
European Union - CE marking, with EMC assessment commonly referenced to EN 50083-2 (cable networks for television signals) - RoHS 2 (2011/65/EU) — restriction of hazardous substances - WEEE — take-back and registration obligations - REACH — substance declaration - Low-voltage / safety directive conformity as applicable
North America - FCC Part 15 — Class A (commercial) or Class B (residential) EMC - UL or ETL listing — often required by MSO procurement and by local electrical inspection - California Proposition 65 — substance warning obligations
Practical advice: if a supplier cannot produce a Declaration of Conformity, an EMC test report and a RoHS declaration on request, stop the technical evaluation there. No amount of price advantage compensates for equipment that cannot be legally deployed.
Our position: HENSURE holds CE marking and RoHS compliance; the Declaration of Conformity and RoHS report are available on request. Certificate numbers and issuing bodies: 待补充。
资质声明边界（勿越线）：FCC Part 15 / UL 或 ETL / SCTE / California Prop 65 无证明材料，本节只陈述"市场要求什么"，不得暗示已持有。
Specification Checklist
Have these answers before you request a quotation:
- [ ] PON type (GPON / XGS-PON / EPON) and wavelength plan
- [ ] WDM filter isolation at 1490 nm (dB)
- [ ] Expected optical input power range at the receiver
- [ ] AGC required? If yes, over what optical window?
- [ ] RF bandwidth required (1.0 GHz or 1.2 GHz)
- [ ] Return path needed (RFoG)?
- [ ] Mounting location and ambient temperature range
- [ ] CE + RoHS required (EU) / FCC + UL or ETL required (NA)
Request a Configuration Review
Send us your wavelength plan and optical power range, and our engineering team will return a receiver recommendation with the filter, AGC window and output level matched to your network.
[Request a Free Configuration Review →] 📧 [email protected] ｜ 📞 +86 533 8172551
HENSURE — CE certified and RoHS compliant manufacturer of optical transmission and CATV equipment since 2015, Zibo, China. Serving cable operators, system integrators and distributors worldwide.