[Amps] FCC Denies Expert Linears' Request for Waiver of 15 dB Rule

Vic Rosenthal 4X6GP k2vco.vic at gmail.com
Tue Jan 3 15:21:57 EST 2017

The TS850S (and probably other transceivers) had an internal pot that 
could be adjusted to set the maximum output. In the service manual, it 
said to set this for 100w output with the drive set in such-and-such a 
way and the RF Output control set to maximum.
If you turned this up all the way you could get perhaps 160 watts from 
the pair of 2SC2879 (I think) transistors.
Of course, in this condition, the IMD was disastrous.

Vic, 4X6GP
Rehovot, Israel
Formerly K2VCO

On 3 Jan 2017 21:39, Jim Brown wrote:
> On Tue,1/3/2017 7:23 AM, Manfred Mornhinweg wrote:
>> Bill,
> <snip>
>> Radios with slow-acting ALC are also famous for causing IMD blasts 
>> and key clicks without even needing an amp, and there are many. But 
>> the most usual way of producing lousy signals is by intentionally 
>> defeating the ALC of the transceivers. In my environment they call it 
>> "liberating" the radio, because the poor radio was tied down to just 
>> 100W by the evil manufacturer, and by defeating that "brake" it can 
>> produce 150W or so, when turning the mic gain to full and then 
>> screaming into the mike, right?
> I can't imagine what you are talking about. Since the days of separate 
> TX and RX, I don't remember ever seeing a rig that didn't allow 
> adjustment of output power.
> 73, Jim K9YC

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