[Elecraft] Is there a reason the receive is so Skinny
Joe Subich, W4TV
lists at subich.com
Sun Apr 27 22:09:58 EDT 2014
> NOW!!!!!
> You have just Describe 98% of those who proclaim their love of
> Contesting!
Hardly - most contesters are focused on keeping their audio "tight"
for maximum efficiency. Yes, some overdrive an amplifier and
splatter but heavily compressed (low peak to average) audio is not
"wide" and does not cause interference. Unlike intentionally wide
audio with excessive low end that rings and creates a false carrier
to the point the SSB can be demodulated as AM.
It takes one look at a P3 or other panadapter to tell the difference
between properly adjusted DX or contest audio and ESSB slop. The DX
or contest audio will show more high end than low end and be 2.4 - 2.8
KHz wide. The ESSB slop will have 20 dB or more low end than high end,
will be 3.5 - 4.0 KHz wide and will sound muddy or 'rumble' with very
little articulation in spite of the extra bandwidth. The excess low
frequency audio will push the transmitter IF and PA stages into
compression much too soon and result audio that is "dense" and full
to tightly packed IMD products of the low frequency (fundamental).
If the transmitter has been modified with a wide IF filter, the ESSB
signal will also include a regenerated opposite sideband down only
10 to 15 dB relative to the normal sideband due to the IMD generated
in the overdriven IF and PA stages.
73,
... Joe, W4TV
On 4/27/2014 9:39 PM, tnnyswy at yahoo.com wrote:
>>>>> willful
> use of a bandwidth in excess of 2.8 KHz can *still* be considered a
> violation in conjunction with other conditions - particularly
> interference, splatter, distortion, IMD, etc. <<<<
>
> NOW!!!!!
> You have just Describe 98% of those who proclaim their love of Contesting!
>
> [particularly!
> interference, splatter, distortion, IMD, etc.]
>
> BTW.
> Aggressive use of Compression (PUNCH)
> Overly active ALC.
> And! Last but not the least, chronic twisting of the mic gain knob
> to the right is tantamount of the above mention.
>
> Maybe, we should just include the Contester in this tantivy as well.
>
>
>
> ((((73)))) Milverton. / W9MMS
>
>
> On Sunday, April 27, 2014 8:09 PM, "Joe Subich, W4TV" <lists at subich.com> wrote:
>
>
>> On the other hand, Title 47 which includes more than Part 97 regularly
>> defines SSB as 2K80J3E (2.8 KHz bandwidth) and specifies a maximum
>> modulating frequency of 2.8 KHz for various FM voice "communications"
>> services.
>>
>> Given that standard, and the fact that RM-10740 was dismissed without
>> modifying the rule that requires the use of minimum bandwidth, without
>> modifying the rules against intentional interference, and without
>> modifying the rule that requires "good engineering practice," willful
>> use of a bandwidth in excess of 2.8 KHz can *still* be considered a
>> violation in conjunction with other conditions - particularly
>> interference, splatter, distortion, IMD, etc.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>>
>> On 4/27/2014 8:42 PM, Milverton M. Swire via Elecraft wrote:
>>>>>>> This issue is not just about "...other hams having fun doing what they
>>> want to do with their K3s", there really are some good engineering
>>> reasons for not using ESSB below 100 MHz. Joe has articulated a few.
>>> Beyond the "...other hams having fun..." argument, is there really any
>>> other reason to do ESSB? <<<<
>>>
>>> David, et al.
>>>
>>> The question of " Legality " and Engineering reasoning has been bantered around
>>> on numerous different occasions.
>>> There are many in their zeal to defend their ideals will make frivolous statements on
>>> what should or should not be the accepted TBW.
>>> Irrespective of what some of us may think, there are no set number on TBW for SSB.
>>>
>>> For those who are about to get their under wears in a wad, here are the FCC view on the
>>> subject a define bandwidth on Phone.
>>>
>>> http://www.nu9n.com/images/FCC-DA-04-3661A1-final.pdf
>>>
>>> There are many of us who often times forget that this is a HOBBY for Amateurs.
>>>
>>> ((((73)))) Milverton.
>>>
>>>
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