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TROUBLESHOOTING WORKSHOP

SWR too high?

Separate measurement setup, cable and antenna before changing antenna length.

Switch the transmitter off before working on the RF path. Never connect a VNA to a transmitting output. Consult each device’s manual for permitted power and SWR limits.

YOUR NEXT USEFUL TEST

Record the frequency response

One point cannot show whether the minimum lies nearby or the whole range is suspect.

  1. Use an analyser disconnected from the transmitter to scan a frequency range appropriate to the antenna. Match calibration and measurement plane to that setup.
  2. Record minimum, target frequency, SWR and setup. Without an analyser, make only permitted measurements according to the manual or arrange help with a suitable instrument.

What to look for next

Return with the response and choose between a shifted minimum and high readings throughout.

Related learning & practice

Technical sources for this check

Background and model-specific guidance; the check sequence is editorial. Match menu names against your own model’s manual.

Show check record
HB3YAQ · Check record: SWR too high?
Your answers; no automatic measurement.

1. Do cable, connectors and antenna connection look sound?
→ Yes, nothing visibly wrong
2. How are you measuring SWR?
→ With a VNA or antenna analyser
3. Is reflection measurement calibrated for this setup?
→ Yes, at the intended measurement plane
4. What does a suitable known matched load show?
→ Near 1:1, within measurement accuracy
5. How does SWR vary with frequency?
→ I only have a single measurement point

Record the frequency response
One point cannot show whether the minimum lies nearby or the whole range is suspect.
1. Use an analyser disconnected from the transmitter to scan a frequency range appropriate to the antenna. Match calibration and measurement plane to that setup.
2. Record minimum, target frequency, SWR and setup. Without an analyser, make only permitted measurements according to the manual or arrange help with a suitable instrument.
Return with the response and choose between a shifted minimum and high readings throughout.

RigExpert Stick 500 · User manual: https://old.rigexpert.com/products/antenna-analyzers/stick-500/users-manual/
NanoVNA · Calibration: https://nanovna.com/?page_id=2

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