CRE 8900 frequency correction

A forum for the discussion of matters of a technical nature. All such activities are undertaken at the readers discretion and own risk. If you don't know what you are doing, don't blame us if it all goes wrong!
User avatar
philippe
Registered New User
Registered New User
Posts: 3
Joined: 13 Jan 2015, 17:41
Call Sign: 14vc110

Re: CRE 8900 frequency correction

Post by philippe »

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
User avatar
Clipper
Super Member
Super Member
Posts: 190
Joined: 28 Nov 2014, 23:40
Location: Lancashire

Re: CRE 8900 frequency correction

Post by Clipper »

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?
cubwolf
Radio Addict
Radio Addict
Posts: 684
Joined: 25 Nov 2004, 23:45
Call Sign: M3CBY
Location: Leicester

Re: CRE 8900 frequency correction

Post by cubwolf »

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
User avatar
Clipper
Super Member
Super Member
Posts: 190
Joined: 28 Nov 2014, 23:40
Location: Lancashire

Re: CRE 8900 frequency correction

Post by Clipper »

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?
cubwolf
Radio Addict
Radio Addict
Posts: 684
Joined: 25 Nov 2004, 23:45
Call Sign: M3CBY
Location: Leicester

Re: CRE 8900 frequency correction

Post by cubwolf »

Yes indeed.
User avatar
dt307
Top Poster
Top Poster
Posts: 1250
Joined: 05 Sep 2014, 16:15
Call Sign: 163dt307

Re: CRE 8900 frequency correction

Post by dt307 »

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




“I fear the day that technology will surpass our human interaction. The world will have a generation of idiots.”
― Albert Einstein
User avatar
dt307
Top Poster
Top Poster
Posts: 1250
Joined: 05 Sep 2014, 16:15
Call Sign: 163dt307

Re: CRE 8900 frequency correction

Post by dt307 »

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
163dt307-chris




“I fear the day that technology will surpass our human interaction. The world will have a generation of idiots.”
― Albert Einstein
User avatar
Clipper
Super Member
Super Member
Posts: 190
Joined: 28 Nov 2014, 23:40
Location: Lancashire

Re: CRE 8900 frequency correction

Post by Clipper »

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