President lincoln mk1 tx audio coming through speaker

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tony2803
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President lincoln mk1 tx audio coming through speaker

Post by tony2803 » 12 Oct 2018, 22:31

Got a slight problem with my mk1 lincoln.
When transmitting on am.fm.ssb i get feedback coming through the speaker. The radio is putting out 10 watts am.fm and 21 watts ssb.
Does anyone have a solution to resolve this problem.
Thanks in advance.

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ch25
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Re: President lincoln mk1 tx audio coming through speaker

Post by ch25 » 12 Oct 2018, 23:11

You can't have too many antennas...

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astradyne
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Re: President lincoln mk1 tx audio coming through speaker

Post by astradyne » 13 Oct 2018, 09:32

The first run of the 2830's and Lincoln's all had this issue. Not sure if it was an intentional function or a manufacturing/design issue, but by the time the Philippines made radio's came out the problem of TX audio coming through the speaker had been resolved.
Never, ever, ever....bloody anything ever!

Far too many radio's to list here. But I do own a legal one...

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Black Spirit
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Re: President lincoln mk1 tx audio coming through speaker

Post by Black Spirit » 13 Oct 2018, 15:06

I have done the 10k resistor and 1n4148 diode in series to pin 6 of the audio amp many times and it works fine.
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tony2803
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Re: President lincoln mk1 tx audio coming through speaker

Post by tony2803 » 16 Oct 2018, 17:32

Thanks for all the replies. Waiting for parts to arrive will post results.

tony2803
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Re: President lincoln mk1 tx audio coming through speaker

Post by tony2803 » 21 Oct 2018, 12:13

Just finished mod 3. Tested and it works perfectly.
Thanks all for imfo.

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