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@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@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
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Sven Ladegast
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