Are you sure Garmin doesn't support the SL-40? I think initially you’ll find that the only place to deal with a repair like that is Sarasota Avionics for a flat rate $964 repair as they are an authorized Garmin shop. Normal turnaround is 10 days when they receive it. You can pay for an advanced repair and get it in 2-4 business days. You can also “buy” one direct from Garmin and have it in a couple days. You will get charged for a full price radio but then they will refund the balance when they receive your unit. The reason you can work with Garmin directly is because you have an experimental. Certified airplanes have to use an authorized dealer. Using the exact same radio means you don’t have to change the radio rack which can be a pain.
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