Fixed the Astron RS-35M

At my work QTH station while attempting to upgrade software on its Flex-6600M the power switch of the Astron RS-35M power supply failed.  Of course I didn’t have a spare RS-35M on the site, as one was a backup at the island QTH station and the other was stored at my home QTH.

Someone asked me “how old was the unit that failed?”  As I acquired it from a local club that was absorbed by another club, I can’t exactly say.  I’d venture a guess that it is more than 20 years old though.

The replacement switches I ordered from Astron have been here since early in the week, but I’d note found time to make the repair until Saturday Nov. 12th before I was scheduled to be at the pool.

To get into the unit you remove power, briefly short out across the output posts to confirm things are deenergized, unscrew the four feet and the three top screws. Then slide the cover off and you are there.

The switch has four “ears” that spring out to secure the switch in the front panel.

With space being limited I broke the “ears” off dead switch rather than risking scraping or scratching the unit trying to compress them enough to pry the switch out.

The Switch Arrangement – notice the clipped “ears” so I could remove it easily

The Switch has bottom wire soldered and then slide-on connectors for the top two wires.

Simple matter to replace the switch. To help you orientate the contacts are numbered and there is an anti-arc shield between the lower two.

Completed Repair of one of my Astron RS-35M Power Supplies

If you notice I have used one of the top cover screws to hold the radio’s RigRunner power/fuse strip in place. One could argue that the RigRunner is redundant as currently used with the power supply also being a fused unit. I use them as I have standardized connectors and protection, and it helps maintain the modularity of the station. Newer versions of this power supply are available with built in Anderson PowerPole connectors.

Flex-6600M completing an Alpha SmartSDR software upgrade


My Flex-6600M is back in operation

(The scribble outs on the photos remove the SmartSDR version number as I am running Alpha Team software across me radios. Only two radios show in SmartSDR as my second Home QTH 6700 is powered off at the moment and the Island 6700 is not left running when I am not there. I did not to the MOV mods Dale N6JSX suggested, as he is working on a short writeup about that mod and I want to order the parts he recommends to do all my units.)



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