[Elecraft] Speech Processors

[Eric Swartz WA6HHQ - Elecraft]

The finals in both the K2 and K2/100 are certainly 'up to the strain' :^).

We designed them to handle way more than you will normally hit them with in a 
processed SSB conversation. In the case of the K2/100 the finals can handle a 
significantly higher temperature than we let them go to in firmware. The 
heatsink and PAs are Ok even when the heatsink is almost too hot to touch. At 
that point we still have a 50 degree safety overhead on the transistors and 
will reduce power automatically before we get much closer to that point. I've 
never seen that happen in normal or contest operation.

When the K2's speech compressor is turned on we actually get some additional 
RF compression by slightly overdriving the '602 balanced modulator (on 
purpose). The resulting out of band IMD is filtered out by the SSB filter, 
resulting in our characteristic punchy SSB sound. I'd expect little 
improvement (and a lot more distortion) from any additional processing.

73, Eric  WA6HHQ
Elecraft


George, W5YR wrote:
> 
> Frankly, the issue for me is whether or not the finals can stand the
> increased duty ratio involved in producing 3 to 6 dB more average
> power output. If they can, then the addition of an rf-based processor,
> such as the Comdel design I described (also used by Drake and Ten Tec)
> or the Vomax audio split-band design, could make a favorable
> difference in the received signal strength and perceived
> intelligibility and "loudness" of the audio.
>