President Lincoln MK1 2SC1674 replacement?

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Vapor
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Re: President Lincoln MK1 2SC1674 replacement?

Post by Vapor »

Well I did the mods and changed resistor to the 1k as I had some of them, wow what a difference, also adjusted the SQ and now no chatter, but the low signal reception is so much better. have ordered a replacement C401 so will get to that later. I can't believe the difference this has made, I can hear such weak signals now.

thanks Chris
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ch25
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Re: President Lincoln MK1 2SC1674 replacement?

Post by ch25 »

Glad you like it :)
Cheers, Chris
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13EL121
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Re: President Lincoln MK1 2SC1674 replacement?

Post by 13EL121 »

This modification comes from DG2IAQ Jochen. Simply replace the 10k with a 1k. Readjusting the coils is not neccessary on most cases.
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Re: President Lincoln MK1 2SC1674 replacement?

Post by radiocom »

ch25 wrote: 01 Nov 2018, 19:53 5.6 kΩ :) Small one. Wattage is not important here.
You can use even 1kΩ, in that case low signals will pass better.
After, check and realign L115 for maximum signal. Plastic screwdriver! Just find on the air fair low FM station and tune L115 for maximum signal. Simple as that.
C401 is located on vertical PCB next to that resistor you will be removing. In case you want to replace it too.

Also it is good to replace C61 from 560pF to 47pF, TX audio will gain high tones, become less muddy.
Chris
sorry to dig up an old post im just modding my lincoln mk1..

c412 is on the fm board next to r412 correct..?
c401 is also on the fm board isn't it not on the vertial board next to the 10kohm res thats the NB pcb..??

thanks sean
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Re: President Lincoln MK1 2SC1674 replacement?

Post by Otter »

ch25 wrote: 01 Nov 2018, 19:53 C401 is located on vertical PCB next to that resistor you will be removing. In case you want to replace it too.
What value do you sugggest that C401 is changed to?
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