[TenTec] Omni VI Plus BFO trimmers

[Bob McGraw K4TAX]

Regarding BFO trimmers and alignments.

The trimmer values and locations are C10 & C12 & C13 are each 4 - 20 
pf.   C16 is a 10 - 60.  C18 is 1 - 6 pf.

As to alignment, I've found the procedure as published in the manual 
must be followed in order as published and all steps must be done, even 
if you do not operate or use one or more of the modes.   There is 
interaction between the adjustments which means you should go through 
the sequence of steps 2 or 3 times.  Also, be sure the radio is 
"warm".   The BFO crystals and components are affected by the ambient 
temperature in the radio.   The frequency will move around a bit thus 
the highest accuracy you can attain will yield better results.    It 
takes patience to get it correct.

73

Bob, K4TAX


On 4/30/2018 8:15 AM, Barry N1EU wrote:
> I believe there are three different values used:  4-20pf (qty 3), 1-6pf,
> and 10-60pf.  I believe the direct replacement I used was a Murata TZ03
> series which are now obsolete.  The trimmers are color coded and it
> shouldn't be difficult to find replacements and you can always find them on
> eBay as a last resort.  Check the lead spacing - I believe it is 6mm.
>
> This is a component that often fails over time, and is fairly easy to
> replace.
>
> 73, Barry N1EU
>
> On Mon, Apr 30, 2018 at 5:26 AM, Barry N1EU <barry.n1eu at gmail.com> wrote:
>
>> I replaced these a while back.  I believe Mouser sells direct
>> replacements.  I'll look through my old email and see if I can find the
>> invoice.
>>
>> Barry N1EU
>>
>>
>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free.
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>>
>> On Sun, Apr 29, 2018 at 9:26 PM, Gary Hendricks <k4mt1950 at charter.net>
>> wrote:
>>
>>> My schematic is so blurry I can tell for sure what the value of those
>>> trimmer are. Looks like 4-20 PF but thats a guess.
>>> Wanted to put some higher quality ones in. Do you have suggestions of
>>> ones that have worked for you?
>>> Gary K4MT
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>>
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