Welcome to the new FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
If you are having a problem, 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.

Flex 6300 ATU

Garyh Member ✭✭
edited November 2021 in FLEX-6000 Signature Series

For anyone who has experienced 6300, 5000 or other radios with add on ATU, issued with tuning not always working, Strange tuning behavior etc.

I wanted to share with everyone that there is a relay on the 6300 and all other flex ATUs that switch the RF into the ATU when its enabled or tuning and switched RF aout of the atu or bypasses the ATU entirely id its not being used.

I first experience this on 2 5000A radios I had. One had the side burned out of this relay. On the 6300 its K3 and sits sideways between the two rows of relays for the matching circuits.

My 6300 would tune once every ten tries and most of the time it would not tune at all. I checked K3 and all the contacts were shorted even the normally open ones were connected with the relay de energized.

I replaced the relay as I had done on other ATUs and now it will tune my 40 M dipole on all bands . On a couple radios I cut open the relay and it was charcoal inside. I wonder if this happens if you try to tune up with no antenna connected by mistake.

Thought this might help others who I have seen reporting ATU strange behavior.

Relay PN EE2-12NUX but a TX2SA-12V will also work

Gary K4MT

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.