[ARC5] Novice receivers.

[Todd, KA1KAQ]

On Mon, Nov 16, 2015 at 7:54 PM, Richard Knoppow <1oldlens1 at ix.netcom.com>
wrote:

>    Well, the Super-Pro began as the SP-100 and definitely pre-dated the
> HQ-120 but there were several models of the Super-Pro.
>

Actually the first Super Pro model was he SP-10 introduced in 1936. The
following year (10 months later, actually) an improved model, the -100 came
along. I believe the -200 was we know it came along in late '39. Of course,
the Hammarlund Comet Pro was the granddaddy of all Super Pros, but the
changes between it and the SP-10 are significant. Just as the changes
between the SP-600 and previous SP-200/-400 are.

Most pre-war -200 models are easy to distinguish from later versions in two
ways: the most reliable way is the front panel - pre-war models were
painted black wrinkle and then engraved with bare aluminum lettering. Not
something you can easily repaint. Another, less-reliable hint is the meter.
Pre-war models had a full glass face while later models captured the
adjustment screw in the metal housing. Since the meters are electrically
identical and could easily be switched, the front panel is a better
indicator along with serial numbers on Henry Rogers' pages here:

http://www.radioblvd.com/hammarlund_super_pro.htm

Though of course, panels that needed repainting got stripped, painted
smooth, then had the engraving filled with paint.

The HQ-120 was introduced in 1938 I believe. Had one of these years ago and
got rid of it, wish I'd kept it. A very respectable receiver, hard to
believe it was Hammarlund's entry-level receiver. Better than most mid and
some high-end receiver offerings from others.

Another interesting tidbit: the SP-10 and -100 used R-meters which require
a bit of ciphering to figure out signal strength. The -200 went to the more
familiar S-meter arrangement. I guess Hammarlund figured any radioman worth
his salt could work out the R-meter reading, probably the same way RME
thought labeling the front panel controls on the RME-69 was unneeded. The
30s was a helluva decade for radio design.

~ Todd,  KA1KAQ/4