[TenTec] Issues aligning Omni 6+ (Mod. 564) FM TX carrier frequency

[Bob McGraw K4TAX]

Decrease the value of C23  to a lesser value such as 68pf.   This should 
raise the frequency.

73

Bob, K4TAX


On 11/8/2018 12:35 AM, Sven Ladegast wrote:
> Hello,
>
> Just to make it clear and to point it out: My problem is located at 
> the FM board and has nothing to do with the BFO xtals at the Audio TX 
> board.
>
> The rig is working fine in SSB and CW and all BFO frequencies are 
> properly set. The frequency I am unable to align is the FM TX carrier 
> frequency and this is aligned with coil L2 on the FM board.
>
> Please see the attached schematics (copyright by Ten-Tec)...
>
> vy 73!
>
> Sven, DJ2AT
>
> Am 06.11.2018 17:06, schrieb Bob McGraw K4TAX:
>> Component aging including crystal.  Tweak the fixed value of the C in
>> the Oscillator. Still the HF Osc for a given band may need adjusting.
>>
>> Bob, K4TAX
>>
>>
>> Sent from my iPhone
>>
>>> On Nov 6, 2018, at 9:42 AM, Sven Ladegast via TenTec 
>>> <tentec at contesting.com> wrote:
>>>
>>> Hello Bob,
>>>
>>> Many thanks for your answer! - I did the BFO alignment already and 
>>> all BFO frequencies are okay, even CW TX is set to 9.00300 MHz.
>>>
>>> Because there is no BFO in mode *FM*, the carrier is produced by a 
>>> separate XTAL on the FM board. This XTAL drives a Colpitts 
>>> oscillator and is tuned by a trimmer coil L2. I cannot get this 
>>> single frequency aligned. The maximum frequency with the core fully 
>>> turned out of the coil is 8.9965 MHz and so my FM TX carrier is 
>>> always almost 1.5 kHz off the RX.
>>>
>>> Though I do not use FM very often, it would be nice if the radio 
>>> does work completely!
>>>
>>> vy 73!
>>>
>>> Sven, DJ2AT
>>>
>>> Am 06.11.2018 16:34, schrieb Bob McGraw K4TAX:
>>>> Perform the BFO alignment in the sequence defined in the manual. All
>>>> steps must be done regardless of the mode you operate or do not
>>>> operate. Be sure the radio is up to operating temp.  Perform the
>>>> sequence 2 or 3 times as there is interaction between the adjustments.
>>>> The set the Master Osc so the radio displays the correct frequency.
>>>> The display is not a true frequency measurement but is a display based
>>>> on the Master Osc. It does not know if the band Oscillator is off
>>>> frequency. Also you can trim each band to get the frequency per band a
>>>> bit closer.
>>>> Bob, K4TAX
>>>> Sent from my iPhone
>>>>> On Nov 6, 2018, at 9:04 AM, Sven Ladegast via TenTec 
>>>>> <tentec at contesting.com> wrote:
>>>>> Hello folks,
>>>>> I do have trouble aligning the TX carrier frequency on an Omni 6+.
>>>>> With no modulation applied, the TX carrier frequency shall be 
>>>>> 9.00300 MHz measured at connector 73 of the board. I used a 
>>>>> TMP-BNC cable and connected it to connector 73 and connected the 
>>>>> BNC connector to my accurate frequency counter using a T-connector 
>>>>> and additional 50 Ohms termination.
>>>>> The TX carrier frequency is aligned by turning the core of L2 but 
>>>>> with the core complete turned out of the coil I get a maximum 
>>>>> frequency of 8.9965 MHz and cannot get to 9.00300 MHz. Do have 
>>>>> anyone an idea what is going wrong? Aged XTAL?
>>>>> 73!
>>>>> Sven, DJ2AT
>>>>> _______________________________________________
>>>>> TenTec mailing list
>>>>> TenTec at contesting.com
>>>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>> -- 
>>> Sven Ladegast
>>> Mühlenstraße 10
>>> 98693 Ilmenau
>>>
>>> Tel: +49-3677-4690104
>>> Fax: +49-3677-4690105
>>> Mobil: +49-160-7997552
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