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Do not solder ground. Instructions mess

EA3IAV
 

Hello I don't really understand what does this mean. The black speaker thing

Note:
Don't solder the ground (black) wire of the speaker to the ground. It should only connect to the speaker or the earphone jack.
You may optionaly route the audio through the supplied stereo earphone jack to the speaker such that if you plug in the earphones/headset the speaker will disconnect. This is left as an exercise to you.


http://www.hfsigs.com/bitx40v3_wireup.html
 

Yes, that is confusing. ?Can probably ignore it.

My guess the intent is that the speaker/headphones should be wired up directly to the speaker/headphone connector on the Bitx40, and that the ground wire from Bitx40 to speaker should not go anywhere else. ?If, for example, you ran the ground return black wire from the speaker over to the ground on the incoming power connector, fluctuations in supply current causing a voltage drop between that power connector and the Bitx40 ground plane would show up in the headphones. ?Though I doubt that would be much of a problem. ?If you wired up the microphone that way it could indeed be a problem, as peak voltage there is only 100mv or so and we are now sensitive to power supply currents during transmit..
Jerry, KE7ER


On Fri, Jun 30, 2017 at 10:22 am, EA3IAV wrote:
Hello I don't really understand what does this mean. The black speaker thing
 

If you plan to use a speaker, it should be wired to the SPK1 header and use those two connections only. Do not try to attempt to ground the speaker to the negative terminal in common with the battery supply.?

If you plan to use speaker and headphones together, you can wire the speaker to the supplied headphone jack. When a headphone is inserted, it will disconnect the speaker and route the audio through the headphones.?

If you look on the schematic, there art two grounds. The audio circuit is on GNDREF. The RF circuit is on GND.?

I don't know what the consequences would be if you mixed the two up. But I don't want to find out.?



On Fri, Jun 30, 2017 at 1:22 PM, EA3IAV <Cesarleon@...> wrote:
Hello I don't really understand what does this mean. The black speaker thing

Note:
Don't solder the ground (black) wire of the speaker to the ground. It should only connect to the speaker or the earphone jack.
You may optionaly route the audio through the supplied stereo earphone jack to the speaker such that if you plug in the earphones/headset the speaker will disconnect. This is left as an exercise to you.




--

Andrew Krause
General Class Amateur Radio License: KM4ZJO
andrew.krause@...
(404) 732-2369
 

Well, you're about to find out anyway: ?No consequences.
Check the back of your board, the SPK1 connector ties into the same big happy ground plane as TUNING1
Some of the ground symbols got labeled "GNDREF" and some did not, but that's all one big ground net.


On Fri, Jun 30, 2017 at 11:29 am, Andrew Krause wrote:
If you look on the schematic, there art two grounds. The audio circuit is on GNDREF. The RF circuit is on GND.?
I don't know what the consequences would be if you mixed the two up. But I don't want to find out.?

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