Yeasu FT7800

This poor little transceiver came in with a report that it was dead, along with a smell of burning. Initially it looks a nightmare to work on, but at least the main board can be removed, albeit after removing 1,232 screws. Looking at the in line fuse in the 12V line, blown. Ummm normally means it’s been connected to a supply the wrong way round. Luck as it would be had, the protection diode was short. Easy job! Replaced and reassembled and a test. Received all okay, but my heart sank when I tried to transmit. Nothing. Dreading the thought of a duff output transistor, started to hunt about. By chance, when in TX mode, I saw a little whiff of smoke from around the output transistor. Thank god this was from a SMD capacitor. With this changed, we had full output. Off for a drink.

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