FAQ
TL;DR: At 50 km from Ślęża, field strength can exceed 70 dBµV during frost; “Using a 45 dB amplifier is a shot in the foot” [Elektroda, irekr, post #10499362] Replace the mast amplifier with a PLN 2 balun, retune channel 58, and DVB-T returns. Why it matters: Over-amplification is the No. 1 cause of missing multiplexes in strong-signal zones.
Quick Facts
• Oborniki Śląskie ↔ Ślęża: ~50 km line-of-sight [Elektroda, irekr, post #10499362]
• Safe pre-amp gain for strong areas: 0–15 dB [Elektroda, irekr, post #10499666]
• 6-69 balun price: approx. PLN 2 (≈€0.45) [Elektroda, irekr, post #10499362]
• Ślęża MUX3 test channel (2012): CH 58 | 770 MHz [Elektroda, irekr, post #10499362]
• Minimum C/N for DVB-T 64-QAM: 17 dB [ETSI EN 300 744]
Why do I receive only TVP channels (MUX3) near Wrocław?
Your 45 dB mast amplifier overloads on strong analog Polsat CH 59, distorting weaker multiplexes; MUX3 survives because it sits lower in the amp’s pass-band [Elektroda, irekr, post #10499362]
Which channels should I get from Ślęża today?
Ślęża now broadcasts MUX1 (CH64), MUX2 (CH36), MUX3 (CH49) and MUX8 (CH10); each multiplex carries 6–8 SD/HD services [Emitel, 2024].
How can an oversized amplifier kill digital reception?
When input exceeds the amp’s linear range, intermodulation rises >25 dB, reducing MER below the 17 dB threshold; the tuner then shows “No Signal” [Elektroda, irekr, #10499666; ETSI EN 300 744].
What is a balun and why does it help?
A 6-69 balun is a passive 300 Ω-to-75 Ω transformer. It passes UHF signals without gain, eliminating overload while matching impedances for <0.5 dB loss [Elektroda, irekr, post #10499929]
3-step fix for the mesh-type antenna?
- Unplug the power injector from mains.
- Swap the 45 dB PCB for a 6-69 balun.
- Fit a metal IEC plug, then rescan CH 58 [Elektroda, irekr, post #10499666]
Why does picture improve when I disconnect the power supply?
Removing power cuts the amplifier, lowering gain by ~45 dB. Noise and intermodulation drop, so analog/digital pictures clear up [Elektroda, MrDrake92, post #10532656]
How do cold nights affect reception?
Temperature inversions boost signal path by up to 10 dB, making distant analog carriers overload local amps, a failure edge-case flagged in February 2012 [Elektroda, irekr, post #10499362]
My Sony Bravia EX3 shows zero channels after scan—what next?
Use manual tuning: enter CH 58, 770 MHz, set digital mode, store when BER <1×10⁻⁶. Repeat for CH 36 and CH 49 [Elektroda, irekr, post #10499362]
How do I verify 12 V reaches the mast head?
Measure at the antenna terminals; you need 11.5–12.5 V DC. No voltage = broken cable or injector; wrong polarity = amp damage [Elektroda, DiZMar, post #10535813]
Should I replace the whole antenna or just electronics?
Keep the mesh reflector. Replace only the PCB with a balun; cost <PLN 5 and fixes 90 % of overload cases [Elektroda, SP5ANJ, post #10500495]
What cabling and connectors are recommended after the swap?
Use RG-6 class A cable and F-type connectors with an F-to-IEC adapter; this lowers leakage by 15-20 dB [Dipol Guide, 2023].
Can overlapping analog channels block DVB-T?
Yes. Analog vision carriers 5 MHz apart create harmonics inside cheap amps, raising noise floor by 8 dB and wiping adjacent DVB-T muxes [Elektroda, irekr, post #10499362]
