[Hammarlund] Cecil Acuff SP600

[Craig Roberts]

Mike Taylor wrote: "Why is it (the SP-600) not good for SSB?

>
> The SP-600 -- like the much lauded and revered R-390 -- does not have 
> a product detector. These receivers were designed before the era of 
> single sideband.
>
> Because these sets have BFOs, however, you can listen to SSB by 
> switching on the BFO (the "CW" position on the SP-600), switching off 
> the AVC, turning up the AF Gain and using the RF Gain as an ersatz 
> "volume control". The BFO pitch control can used for fine tuning.  The 
> method's a little crude when compared with the ease and stability of 
> our "modern" receivers from the late '50's on, but it works.
>
> Product detctors, both outboard and inboard, can be purchased or 
> constructed to make sideband reception more viable on these old 
> radios, but these sets are at their best on wideband AM -- which is 
> what they were designed for.  By the way, when carefully tuned and 
> employing the crystal filters, the SP-600 makes a marvelous and 
> wonderful-sounding CW receiver.
>
> 73,
>
> Craig
> W3CRR
> www.aerialacts.com
>