Rob:
This is interesting. My C 22 has low drive on 80 m as well. It seems to
get worse as the rig warms up. I checked the 80 m bandpass filter and
it looks OK. I am thinking that maybe the 80 m crystal, which is 10 MHz,
has low output and I was about to replace it, but first I'd like to
learn what the 40 m null pot does and how it affects 80 m. By the way,
the 80 m bandpass filter is not adjustable, but the filters for the
other bands are.
I have an original manual plus a downloaded one (not from Ten Tec) which
has a note for setting driver and final bias, but nothing on the null pot.
Please let me know what you find out.
Thanks.
73,
Bob WB2VUF
Rob Vaughan wrote:
> Hi Walt,
>
> Thanks for the reply. I downloaded the manual available from Ten-Tec online
> (previous owner still looking for the original ;-) before I even picked up
> the rig and there is no alignment procedure in there.
>
> There is no description of what the "40m null" adjustment does or hint on
> how to adjust it. Just a pic of the board that identifies it.
>
> Anyone have the alignment procedure, or can I ask Ten-Tec for a copy of
> that?
>
> Thanks and 73,
>
> de VE3XGB - Rob
>
>
> ----- Original Message -----
> From: "Walt Amos" <waltk8cv4612amos@att.net>
> To: "Rob Vaughan" <robvaughan@sympatico.ca>
> Sent: Tuesday, April 20, 2010 10:50 PM
> Subject: Re: [TenTec] Century/22 power out
>
>
>> If you have the manual or can download it the alignment sequence is
>> spelled out. Naturally you can send it to TenTec but that would probably
>> cost more than the rig is worth. Someone probably aligned it with out
>> taking the 40 M null into consideration or didn't know about it and it is
>> eating the 80M signal.
>>
>> Walt K8CV Royal Oak, MI.
>>
>>
>> ----- Original Message -----
>> From: "Rob Vaughan" <robvaughan@sympatico.ca>
>> To: <tentec@contesting.com>
>> Sent: Tuesday, April 20, 2010 8:03 PM
>> Subject: [TenTec] Century/22 power out
>>
>>
>>> Hi All,
>>>
>>> Recently took ownership of a Century/22 that I really like but a little
>>> bit disappointed by the "20 watts out" claim. Mine puts out about 15W on
>>> 40m and 30m, but as little as 8W on 80m and 6W on 10m. It would be nice
>>> to have closer to 20 especially on 80m where noise levels are higher of
>>> course. I put my ammeter inline with the power supply and can see it
>>> only draws 2.5A when the drive control is full clockwise on 80m whereas I
>>> can drive it to 5.5A on 40m well before full clockwise drive and cause
>>> the 979 supply to cut-out (as its supposed to).
>>>
>>> When I spoke to Paul at TenTec he suggested it could be the 80m bandpass
>>> filter (would that show low current though?) or that perhaps the "40m
>>> null" adjustment needed adjusting. He said that can impact output on
>>> 80m. I should have asked him what it does because I don't understand this
>>> adjustment. Perhaps someone out there can explain it to me. Don't want
>>> to go adjusting something before I know what the impact/pitfalls are.
>>>
>>> Thanks for all the help and 73,
>>>
>>> Rob - VE3XGB
>>> _______________________________________________
>>> TenTec mailing list
>>> TenTec@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/tentec
>>
>
> _______________________________________________
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> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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