Transponder monitor — what a satellite or network carries, and what changed
Updated 27 Oct 2026The transponder monitor uses a free tuner to go through the transponders of a satellite, a cable network or a terrestrial network on a schedule. For each transponder it records the lock, the signal, the bitrate, TR 101 290 and the services, and after every run it shows what changed since the previous one: a new transponder, a service that disappeared, a renamed programme, a different provider, scrambling switched on, other tracks.
Available since Castreon 3.0.0, in the Enterprise edition.
What you need
A tuner that no enabled adapter is using: a card in the server, or a SAT>IP server (position src). The tuner is busy only while the monitor runs; if an adapter takes it in the meantime, the monitor waits and tells you why.
A new monitor
Transponders (menu) → New monitor:
- Name, Delivery (DVB-S/S2, DVB-C, DVB-T/T2, ATSC, ISDB-T, DTMB…) and the Tuner — Card in the server (adapter / frontend) or SAT>IP server. For satellite: LNB, DiSEqC port, tone burst — like an adapter.
- Mode:
- Network (NIT) — starts from a known transponder (Start transponder), reads the network map and goes through every transponder it announces. The fastest. Neighbouring networks too also follows the NIT of other networks on the same satellite.
- Blind scan — goes through the band from From to To with the chosen Step, polarizations and Symbol rates tried, and also finds transponders the NIT does not announce. It takes longer; the form shows an estimate.
- List — only the transponders you write, one per line (satellite:
11778 V 27500; cable:306 6900; terrestrial:674).
- Measurement per transponder — seconds spent on each locked transponder for bitrate and TR 101 290;
0= tables only (faster). - Schedule — on demand only, daily at a time, or every few hours. Notifications sends the changes through your notification channels (the “DVB sources” family).
Run now starts a run at once; while it runs you see the progress (“12 of 48 · now 11.778 V”) and you can Stop it. A stopped run gives a partial report that is not used for comparisons.
The report
Each run keeps a report with three tabs:
- Changes — compared with the previous complete run: transponders appeared, gone, locking again or no longer locking, changed parameters (frequency, symbol rate, delivery), a different mux on the same frequency; services added, removed or renamed, other provider, type (for example SD → HD), free ↔ scrambled, other conditional-access systems, other tracks (PID, codec, language). The first run only builds the reference.
- Transponders — frequency, network (ONID / TSID), signal and quality, bitrate, number of services, and where the transponder came from (start, NIT, other network, blind scan, list).
- Services — name, provider, type and access (free / scrambled, with the CA systems), searchable by name, provider or SID.
A report can be downloaded as CSV (one row per service, for spreadsheets) or XML (the whole report, for other programs).
Tips
- For a whole satellite, Network (NIT) once a day is usually enough; keep Blind scan for satellites with feeds that are not announced.
- Point the monitor at the satellite your channels come from: a renamed or moved service shows up in the report before viewers notice.
- On a motorized dish, a monitor and the adapters share the dish — use a separate dish or LNB for the monitor.