If you find yourself getting unusual noise from your one-piece wireless transmitter on your guitar or bass, you may have a noise injection issue. Noise injection is most often noticed in ultra-low power preamps when using guitar transmitters that use a 3-conductor TRS plug.
There are a few factors that can cause this:
- Proximity of the transmitter to the control cavity,
- Shielding of the control cavity,
- Use of one-piece transmitters with TRS plugs.
Compact one-piece transmitters use the RING and SLEEVE of the plug to recharge their internal batteries when docked. This requires an electronic circuit to monitor the RING and SLEEVE connection to see if the unit is docked or plugged into an instrument. It also means that closing the RING & SLEEVE connection (which acts like a power switch inside the instrument) is done electronically.
Instead of a mechanical switch that completes the circuit inside the instrument (no opportunity for external noise to be introduced), switching happens OUTSIDE the instrument inside the transmitter using active electronics.
Ultra-low power preamps like the LHZ and others can confuse the monitor and switching active circuitry inside the transmitter. In some cases this will result in power fading in and out or the injection of a high frequency tones or static.
Link to PDF shown in video: https://lhzpreamps.com/wireless/