Re: Ubitx audio debug question
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Tom,
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First check your audio amp. Keep the volume midway and If you touch the volume control leads you should hear a hum in the speaker. A picture of your U1 TDA2822 will help. You should hear a hiss even with a dummy load. A few feet of wire for an antenna should bring in some signals. Raj At 3/5/2018, you wrote:
Hi, ubitx-ers! I've assembled my ubitx, but have no audio out of speaker jack. I've double-checked the brown & black wire connections all the way from the exposed debug speaker I built to the connector on ubitx board via my 3.5 mm connector and jack. The debug speaker works with my cell phone audio so I know the external plug, wiring, and speaker are ok. The audio 10k pot is correct with orange and yellow corrections from forum and pot checks ok with oh meter. The display comes on 40 meters with no tx. The idle current draw RX into a dummy load is about 160 ma at the DC input. I plan to continue debug, but have a basic question: shouldn't I hear some sort of audio static even while connected to a dummy load? |
Raj vu2zap