From curt at wbph.org Fri Jul 30 12:42:02 2021 From: curt at wbph.org (curt at wbph.org) Date: Fri, 30 Jul 2021 12:42:02 -0400 Subject: [SBE] Questions about UHF amplifier repairs Message-ID: <07d59abbb30252c640490531b2ed4d0f@wbph.org> Hi, all! Does anyone have any experience fixing UHF amplifier circuits built around the BLF878 LDMOS power transistor? Are there any tricks to testing one out-of-circuit to verify if it's even any good? I've got a Linear AT72K5 transmitter with one bad module in one of the amplifier trays. The troubleshooting I've done so far indicates which module, so I've narrowed it down that far. But I can't seem to pin down whether the problem is the BLF878 itself, or something else on the board. I managed to salvage a couple spares from a slightly older version of the same amplifier design, but I can't say for certain if they are viable either. Thanks in advance. Curt -------------- next part -------------- An HTML attachment was scrubbed... URL: