[Elecraft] An interested link

[Hector Padron]

This is how I see the use of ESSB, nobody should have more than 3Khz maximun bandwith on TX,with less than 3Khz you will be able still to have an excellent audio quality,normally a radio that has a freq response from 100 to 3100 Hz for a total of 3Khz BW will always sound great so far mic and comp levels be properly adjusted not to compress the audio too much,even Icom radios that respond from 70 to 2900hz sound all terrific,but anything beyond that bandwith will sound moody and splatters will be terrible all over.
On the other hand splatters are not only confined to ESSB,a normal high pitch or normal 2.4Khz bandwith could also has same or maybe more splatters IF the operator doesn't know how to properly set his station,probe of that is the contests where most of the stations trying to brake the pile-ups sqeeze their compressors to the maximun and also overdriving their amps to reach the station they want and therefor band becomes the battle camp and splatters are all over.
So either way ESSB or non ESSB can create damage to the bands.
Its just good amateur practices what makes a clean signal.
 
AD4C

"To have or not to have a K3,that is the question"

--- On Sun, 9/27/09, David Cutter <d.cutter at ntlworld.com> wrote:


From: David Cutter <d.cutter at ntlworld.com>
Subject: Re: [Elecraft] An interested link
To: "Dave G4AON" <elecraft at astromag.co.uk>, elecraft at mailman.qth.net
Date: Sunday, September 27, 2009, 2:19 PM


There might be 2 distinct problems:  a) the bandwidth of the signal you 
think you have and b) splatter caused by over-modulating and over-driving.

Starting with a wide-ish signal of say 6 or 7kHz, ie dsb full carrier might 
be ok in uncrowded bands, but add badly adjusted modulation and drive to 
another badly adjusted amplifier (a non-linear linear amplifier) and you've 
got double trouble that can be heard across the world even worse than 
over-driving ssb.  Couple that with the sort of drift those boat-anchors are 
capable of and I can see why they have a bad reputation.  All of which can 
be corrected by proper adjustment which takes more skill and understanding 
not now taught.


David
G3UNA



> Fortunately the K3 is quite good on AM transmit, unlike legacy equipment
> often used. I don't know about elsewhere, but here in the UK there are
> 80m AM nets where some of the stations run original AM gear without any
> additional audio filtering, one was measured at +/- 12 KHz by a fellow
> ham with an SDR receiver. The operator seemed indifferent to the fact
> his transmission was excessively wide and carried on regardless. The guy
> who measured the wide signal used home built AM gear himself, but had a
> multi-pole active filter of a similar specification to that used by
> broadcast stations to achieve their "skyscraper" envelopes as seen on a
> panoramic adapter or SDR receiver.
>
> The UK license has the clause "The bandwidths of emissions should be
> such as to ensure the most efficient utilisation of the spectrum".
>
> 73 Dave, G4AON
> K3/100 #80
>
> Joe, W4TV wrote:
>
> Similarly, AM - except for legacy equipment - should be
> limited to 6 KHz bandwidth. In other words, the maximum
> modulating frequency should be set at 3 KHz - or no more than
> 3200 Hz.
> 
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