MTR3B switch repair

Looking for help repairing my MTR3B. I tried contacting LNR Precision via the website, but I can’t get my query to submit on their contact form.

The down button is working intermittently, so I figure I need to replace it. It is a newer model, I got it just over a year ago. I don’t know if the trip will go with the Covid lockdowns, but our family has a five day SOTA expedition planned in June, and I am concerned the button may fail during that trip. I thought about using the direct frequency entry as a backup, but the same malfunctioning button is needed to load the frequency after entering it.

Does anyone have a suggestion for a replacement part?


Hi Will,

Pretty easy fix. Take off the cover and you can see where those switches are attached to the board. Have a close look at the solder joints - the switch might be fine but the connection to the board is becoming flaky.

If the switch is bad they are very common PCB mounted switches. You would need to desolder the old one and solder in a new one. Someone on here might have a part number for the exact switches so it matches the others.

Good luck… ping me if you get desperate =)

-Josh WU7H

Thanks. I tried resoldering earlier today, no change. I feel okay about my soldering after learning with a few QRP Labs QXC kits. But ordering the right part number is my concern. I tried ordering some parts from Mouser for a different project, and after spending a long time trying figure it out, I still got the wrong items.

I have some of those switches. I can mail you one. - Fred KT5X (aka WS0TA)


There is quite a lot of knowledge about parts, fixes etc on the groups relating to Steve’s designs. Older rigs - ATSPRINT group. Newer rigs - KD1JVdesigns.

73 Andrew VK1DA/VK2UH

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I have a similar issue on my MTR5B but not bad enough to encourage me to strip the rig just yet!
The switch is a common part, I got a bag full via ebay for a couple of British Pounds.

It might be easier to destroy the faulty switch and bring each leg out at a time rather than desolder the whole unit.

It is possible to do these repairs, I just swapped a slide switch on an MTR-2B for someone.

Good luck,



Thanks for the help–I received the switch and got it installed–working like new. Thank you!


Nice work! CU on the air. 73 fred