[Amps] New SB-200 owner

[Roger Halstead]

> Roger said:
>>More than likely I'd move on to the ARRL Handbook and build a PI-L network
> for the desired Q at the operating frequency which in this case is 50 to 
> 54
> MHz.<
>
> Is there any advantage in using a pi-L, rather than a straight pi and 
> suitable low pass or bandpass filtering to get the harmonics down?

Probably not overall, but I like to keep the harmonics down in the design as 
much as possible.  The filters would probably do as good a job.

> Especially since we're talking of a single band amplifier that needs to 
> have the second harmonic at least 70dB >down, and I doubt a pi-L will do 
> that on its own

Considering I'm close to a lot of homes using off the air TV the external 
filters will probably be a necessity any way, although I've not run into any 
problems ...yet ... with the HL-1.5Kfx solid state amp. OTOH they have 
filters switched in for each band internally.

> Does the pi-L give a greater impedance matching range for any given Q 
> variation or something? Although I'd have thought that on 6, you'd be 
> looking at pretty low SWR anyway.

To that I have to plead guilty to actually not knowing.

73

Roger (K8RI)
>
> 73
> Peter G3RZP
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