[Hallicrafters] SX-73 VS: SP-600-JX Comparision question

[rbethman]

Richard,

I can't speak to the specific issues of the SX-73, BUT - The SP-600s can 
be aligned to the same sensitivity levels as an R-390A.

I've not found a Hallicrafters receiver with that ability, with the 
exception of the SX-28s.

I've known several hams that have restored the SX-73s, BUT never spoke 
as highly of it as an R-388 or an R-390A.

Bob - N0DGN

On 11/3/2010 5:14 PM, Richard Knoppow wrote:
>        I have long been curious about the relative
> performance of the SX-73 and SP-600-JX. The SX-73 was
> obviously built to meet the same military spec and bears the
> same military type number. It is not a clone but a unique
> design. I have seen very few and never actually used one. It
> has some features that look interesting such as regulated
> filament voltage for the oscillator. I've found that the
> SP-600-JX drifts with line voltage changes due to
> sensitivity of the filaments to the variation. It also
> appears to have a less delicate turret mechanism. I am
> curious to hear from those who actually have these receivers
> and can tell about their performance and how difficult or
> easy they are to work on. One merit of the Hammarlund RX is
> that its relatively easy to repair despite the complexity of
> some parts.
>       Also, does anyone have any idea of how many SX-73s were
> built and over what time period.