Welcome to the FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
The latest SmartSDR Software:
SmartSDR v4.2.20 | SmartSDR v4.2.20 Release Notes
SmartSDR v3.10.15 | SmartSDR v3.10.15 Release Notes

The latest 4O3A Genius Product Software:
The latest 4O3A Genius Product Software and Firmware
How to Receive Technical Support::
If you are needing assistance with FlexRadio products, please refer to the product documentation or check the Help Center for known solutions. Need technical support from FlexRadio? It's as simple as creating a HelpDesk ticket.

Microphone Cable RF problems and Cable needed for Heil PR 781 connections

GDECASTRO
GDECASTRO Member ✭
edited November 2025 in Peripherals & Station Integration
Hello, 1. I do have a request for hams that had experience Radio frequency on the transmission with the microphone FMH3 on a 6400M or should I limit the question to the cable of the mentioned microphone.
2. what is the best cable to connect to a 6600 M a Heil PR781 ?
Thanks
Tagged:

Comments

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    Which mic input do you intend to use? Balanced or pseudo-balanced?

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭
  • GDECASTRO
    GDECASTRO Member ✭
    I do not the answer to your question
  • GDECASTRO
    GDECASTRO Member ✭
    I do not know the answer to the question
  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    critical for selection of proper cable.

  • WX7Y
    WX7Y Member ✭✭✭✭
    edited November 2025

    On the Heil PR741 which is a Balanced MIC if your troubled with RFI getting into your MIC Audio I would keep it all Balanced on the radio. I would buy a XLR to fit the PR741 MIC to a 1/4" Phone plug for the FLEX6600/ 8600 like is used in the Music industry like this one on AMAZON

    https://www.amazon.com/Tisino-Female-Balanced-Interconnect-Quarter/dp/B07JVBS78Z/ref=sr_1_5?crid=2O0Z3XEI146W3&dib=eyJ2IjoiMSJ9.Z6Oa2CwhHcYm_VI49Mc31sdUfUwXo_iRMuA3P_Mf4nnXzdjc1LofO287f3lFzKDPFn2_v-tqx5MsPzwNYAqNubNbReRYc-okKqOzKUkMnDZ0aYw3I4czHF4MyPtPkZGTqRFfUkv5QhoF0GN9VYKxKfNFGbQj6ZfkyIg7c5eLjunVLkKnZfjNhDeDcPsuEVRThLrxzd0rfJ1GbLHIspadaaXzR9O9cBM0fPVGi_mveIA.5MitvwIQQkA8OM5iL0iKIFKrvu7D4OQCknUAAUMpGVQ&dib_tag=se&keywords=XLR%2BMIC%2Bto%2B1%2F4%22%2BPhone%2Bplug%2Bcable&qid=1763926476&sprefix=xlr%2Bmic%2Bto%2B1%2F4%2Bphone%2Bplug%2Bcable%2Caps%2C159&sr=8-5&th=1

    On the 6400 it does NOT have the Balanced input but just the 1/8" pseudo-balanced which MAY NOT help with your RFI because it ties the MIC-- and signal to Ground together.

    Hope this helps and 73

    Bret WX7Y

  • GDECASTRO
    GDECASTRO Member ✭
    Thanks a lot

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.

Comment As ...

Categories