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Vernon
Posted on Wednesday, September 19, 2001 - 7:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok, I have a COBRA 2000 , and when I am on LSB, and I am in the center-slot on the clarifier, and most of the stations I talk to sound perfect, and I sound perfect to them , my frequency display reads 27.405.2 can I adjust the frequency display without changing the transmit recieve ?.
The display itself is a little off, about 2 kc.
I thought there may be a variable in the radio to calibrate the display only. Any ideas?
Thanx.
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Skullman
Posted on Thursday, September 20, 2001 - 6:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hiya Vern, the only adjustments I have for the 2000 don't list a vr for the freq. display. Although, I do have a fix for an unstable counter. It says to locate D528(XZ057) in the freq. counter module. This is a 5.7 volt 1/2 watt zener diode. Replace with an NTE-136A 1 watt to cure the problem. Maybe that will help. If you need the VR adjustments email me at skullman858@yahoo.com or I can post them here.
Hope any of this helps.

DEADMAN INC.
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307
Posted on Thursday, September 20, 2001 - 7:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi , Yes you can , set the clarifier to dead center and adjust L30 (next to VR4) to match TX with RX while in TX mode , you don't need to modulate , It will move it. Please let me know...
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307
Posted on Thursday, September 20, 2001 - 7:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

After reading the post the second time , you may be wanting to "center it up only". For this adjust L-23 , L-22 and L-59 for AM , LSB and USB respectfully..
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Vernon
Posted on Sunday, September 23, 2001 - 5:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok 307, thanks for the answer, now can you tell me the same adjustments for a Lafayette ssb 140? It has the PTBM048A0X main bd.. AM is ok, but SSB is way off, I have people tell me they have to clarify me at 1:30.
Thanks in advance.
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Adshar64
Posted on Monday, May 19, 2003 - 7:31 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Do a proper alignment and frequency check. all good and counter still out?
Take off counter top shield and on right far centre side you will see a variable red cap against edge near the two tuning coils this will adj your readout to suit your correct 12 oclock true frequency. I had trouble with the range on mine and put some external small caps in parallel to bring into range esp when aligning usb and lsb correctly.

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