CRE 8900 frequency correction

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philippe
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Re: CRE 8900 frequency correction

Post by philippe » 22 Jan 2015, 16:15

Hello, I also have a cre8900 that ssb and lsb is shifted in frequency: 27413 to 27410, being too quirky I can not have it any further changing the setting of BF have an idea .... thank you

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Clipper
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Re: CRE 8900 frequency correction

Post by Clipper » 08 Aug 2018, 12:28

Recently found that my DR-135UK was out by ~2kHz on LSB (display shows 27.343 when listening to Portuguese on channel 34 midband). Adjusting the BFxxx value can't correct it as the value only goes down to 130 and it seems that it could do with being a lot lower..

Anyone know if there's any other frequency adjustment either software or on the circuit board?

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Re: CRE 8900 frequency correction

Post by cubwolf » 15 Aug 2018, 19:48

Change the 10.240 xtal. There isnt any adjustment so you need to find one will work properly. I did an alinco dr-135 a while ago and that cured it

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Re: CRE 8900 frequency correction

Post by Clipper » 16 Aug 2018, 13:53

Thanks cubwolf, I assume the dodgy crystal frequency is close enough to be unnoticeable when using FM & AM but far enough out to be a PITA on SSB?

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Re: CRE 8900 frequency correction

Post by cubwolf » 18 Aug 2018, 00:05

Yes indeed.

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dt307
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Re: CRE 8900 frequency correction

Post by dt307 » 18 Aug 2018, 21:12

posted a fix for the not able to adjust the bf enough

viewtopic.php?f=53&t=54046&p=488322&hil ... cy#p488322
163dt307-chris




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dt307
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Re: CRE 8900 frequency correction

Post by dt307 » 18 Aug 2018, 21:16

on some china radios that i known were good and the owners aint played with things have jumped high in frequency around 100hz because of a cap going open circuit ,and as its smt most cant do it so adding a small cap 1-3pf can get you back into the bf adjustment range to correct it
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Clipper
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Re: CRE 8900 frequency correction

Post by Clipper » 20 Aug 2018, 08:47

Chris - thanks very much for the link, I was hoping this kind of info was out there! :thumbup:

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