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Icepick
Member
Username: Icepick

Post Number: 61
Registered: 1-2002
Posted on Sunday, February 20, 2005 - 11:44 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi My 2000 used to have an eratic freq. counter. That was fixed w/ a diode. Worked fine for about a month. Now the recieve and transmit freq. starts out at 27.3725 and slowly fluctuates up to 27.3748, 49,50 and sometimes back again while warming up. Almost like unstable voltage from somewhere. By the way, the clairifier is unlocked. Has anyone ever had this problem before??? Please help. Many thanks, icepick
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Racer_x
Junior Member
Username: Racer_x

Post Number: 17
Registered: 2-2005
Posted on Sunday, February 20, 2005 - 4:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

All radios drift from cold to warm and 250 Hz isn't too much - especially if the clarifier swings a lot.
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Kid_vicious
Intermediate Member
Username: Kid_vicious

Post Number: 222
Registered: 9-2004
Posted on Monday, February 21, 2005 - 1:29 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the voltage regulation of the clarifier circuit in the 2000gtl will not remain stable past a certain khz of slide off freq. im not sure, but over time this may cause a degradation of the regulation! LOL
also, replace the big cap in the power supply. use a slightly larger value than stock.
matt
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Icepick
Member
Username: Icepick

Post Number: 62
Registered: 1-2002
Posted on Wednesday, February 23, 2005 - 8:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks you guys.... I'll try the cap replacement first. No offence Racer X, but None of my other unlocked radio's are this far off; especialy in the constant temperature of my house. But thanks for your imput just the same. Very much appreciated !!!! Ice pick
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Racer_x
Junior Member
Username: Racer_x

Post Number: 30
Registered: 2-2005
Posted on Wednesday, February 23, 2005 - 10:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Do the other radios swing as far as this radio does? Depending on how the clarifier mod is done it makes the VCO less stable and it'll drift more from cold to warm. If it's got a really large swing it'll continue to drift even when warm.

I spent some serious time on the air several summers ago working on frequency adjustment of lots of SSB radios with friends. We probably looked at more than 50 radios total. Most were currently available rigs at the time and included Uniden, Cherokee, Ranger, Galaxy, Cobra, SBE, Realistic, Kenwood, Icom and others. We did this so we could chat with everyone on the SSB frequency we used without much hassle. At one point we had over 2 dozen regular locals and at least that many occasional visitors on our frequency. Having everyone on frequency was a must, and not everyone was comfortable with opened clarifiers.

It started with one friend asking for my help with a radio he had just bought and thoroughly aligned, and it turned into a nightly activity for at least a month.

Most radios drifted at least 100Hz and some drifted more than 300Hz. The CB radios I found to drift least were Uniden boards which were typically 150Hz or less, and the one that drifted the absolute least was a Stalker XX. From stone cold to warm it drifted only 50Hz! That's only slightly more than my Kenwood TS450 which doesn't have a TCXO unit installed.

I used my Kenwood TS450 as a reference because once it was warm it didn't drift much at all. I could tune to WWV to zero beat it so it was exactly on frequency, and I could easliy return and check it against WWV from time to time.
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Icepick
Member
Username: Icepick

Post Number: 63
Registered: 1-2002
Posted on Friday, February 25, 2005 - 7:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You could be right Racer! I'm no expert at this by any means, so I'll try anything and every thing. If the cap mod dose'nt work..... I'm going to Re-Lock it again. I've never liked open clarifiers anyway!!! If I wanted slide,.... I would have got an external VFO. But this is how it came. Thanks Racer X !!

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