[Hallicrafters] Re: More questions on SX-100

[Ken Kaplan]

Phil,

Well I have an HQ-180AC and an SX-100 Mk 2. Both are in CCA excellent condition. 
I've found that the HQ-180 is drifty compared to the SX-100. I always have to tweek 
the Vernier Tuning on SSB transmissions. One of these days I'm going to try to find 
out why. It always sems to drift is one direction. I can turn the SX-100 on and after a 
short warm up (1 or 2 minutes) it will be right where I last had it and hold reasonably 
well. I'm not so sure I can say that about the HQ-180.

Tuning SSB signals on the SX-100 is easy. Just get it close and then adjust the Pitch 
Control. There is no adjustable AVC speed on the SX-100. I don't find that a big deal. 
The noise limiter on the SX-100 is an on/off kind and it distorts the audio a bit. I like 
the HQ-180 variable limiter a bit better.

Subjectively, I like the sound I get from the HQ-180 when playing with the selectivity. 
Adjacent signals seem a bit easier to suppress with the HQ-180. I use a Heathkit 
HD-1418 active audio filter which can sometimes help a lot with adjacent signal 
suppression. I should state that I'm almost exclusively an earphone user. I don't care 
about hi-fi shortwave.

My SX-100 is my latest BA acquisition. Am I glad I got it? Absolutely. It performs 
quite well and I think it looks great. Do I like the HQ-180? Absolutely. It also performs 
quite well (some might call it "hot") and it looks good in a more industrial sense. The 
HQ-180 certainly is a bigger box. Be aware that unlike the HQ-180, the SX-100 has 
some paper capacitors that may need replacement.

I find the HQ-180 to be easier to spot a particular frequency. The SX-100 has 
bandspread marks every 200 kHz on 80M. Using the skirt on the SX-100's 
bandspread knob, you can just resolve 2kHz. The HQ-180 dial can resolve to 500 
Hz. I've never had my hands on an SX-71 but its panel reminds me of a National NC-
98 I once had. The NC-98 was not an accurate rig.

For accuracy, stability, selectivity and all of the other things we would like in a BA, I 
find my Hammarlund HQ-215 and my R390-A are probably my best receivers. 
Problem is the HQ-215 is only a Ham receiver.

I don't know why Hallicrafters did what they did with tube selection. Maybe they had a 
warehouse full of 6SC7's and 6K6's that they had to use up <g>. Like you, I've 
thought of giving VLF a try. I have a Heathkit HD-1420 but I just haven't gotten 
"roundtoit" nor do I know much about it. My BA corral contains an SX-100, SX-28A, 
HQ-180AC, HQ-215, R390-A and an SB-100. Yes there are a couple of "things" out 
in the shop but they don't work so they don't count <g>.

Sorry for the long winded answer. Get the SX-100. If its a good one, you'll like it.

73 Ken kb7rgg

> Hi All,
> Please bear with me, I am much more familiar with "hands on" use of
> Hammarlund gear than I am with the Halli's as they've usually been "my
> receiver of choice" (outside of the SX-71, 5R10A and S-120 that is).
>
> The SX-100 sounds nice, but I want to be CERTAIN!
>
> 1.  For comparison I suspect the "Flagship" HQ-180A is probably
> Hammarlunds nearest equivalent to the SX-100. How do they compare in
> operation, reliability and stability (or for that matter the Hammy
> HQ-145X vs the SX-100)?  
>
> 2.  The receiver will be used EXTENSIVELY in the 80M band  with an LF
> converter for Longwave beacons.  Towards this end, what scale markings
> does the bandspread have and how accurate are they? (I.E. 10KC, 20 KC
> increments etc).  My SX-71 has 20KC increments and they aren't very
> accurate across the band.  In fact, on the SX-71, if you Cal it at 3.5 or
> 7MC etc, bandspread calibration is rather sucky.  I'd LIKE to be able to
> determine the bandspread frequency within 5KC/less without adding an
> outboard counter.  
>
> 3.  I wonder why Hallicrafters chose to use miniature tubes in the SX-100
> but stayed with the venerable 6SC7 Octal and 6K6 combo when other
> manufacturers had long switched to all miniatures.  Reason I ask is the
> 6SC7, at least in my SX-71 has proven to be noisy in BFO service,
> requiring it to be replaced 2-3 times (and yes, circuit components are
> good).  It "seems" like I have a good one in there now.  I hope it
> performs better in the SX-100. 
>
> 73 from the "Beaconeers Lair".
> Phil, KO6BB