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Re: Short Wave Vs 2-Meter Ham Band frequencies for UT
From: Paul Hirose
Date: 2015 Nov 09, 22:50 -0800
From: Paul Hirose
Date: 2015 Nov 09, 22:50 -0800
On 2015-11-09 2:07, Steve E. Bryant wrote: > 2. "C Crane CCRadio-2E Enhanced Portable AM, FM, Weather and *2-Meter Ham Band*." > My question is with regard to the second choice above. > Does the 2-Meter Ham Band frequencies necessarily mean that the radio will be capable of picking up the stations that broadcasts the time signals? > And the follow up question is: Which of the two radios would have the best reception for my purpose? Steve, when you ask a question like that it's helpful to provide links to Web pages so respondents can see exactly what products you're asking about. If I identified your #2 correctly, it doesn't get shortwave frequencies so it's not suitable as a time standard. That leaves only #1. Recently my 1980s Sony ICF-2010 died so I bought a Tecsun PL-660 portable because it has gotten good reviews. Price was $110 from Universal Radio: http://www.universal-radio.com/catalog/portable/2540.html I'm really pleased with it. At $110 you can't expect a high class radio, but it's a fine value for the price. In some ways it's better than the Sony, which as I recall was $300+ back in the 80s. Wide and narrow bandwidth filters can be selected regardless of mode, and the narrow filter sounds better than the Sony's. The latter killed too much of the highs on AM for my taste. The Tecson sync detector works, though there's noticeable tonal difference when you switch between the upper and lower sideband. The Sony wasn't like that. I suspect the reason is that the Tecsun only tunes at 1 kHz steps vs. 100 Hz for the Sony, so you can't put it as close to the carrier freq. But that's just a guess. Happily there's a continuously variable BFO knob, so single sideband voice can be made to sound right despite the 1 kHz tuning steps. And SSB mode isn't just for single sideband transmissions! Very weak AM signals can become readable in SSB mode. This trick works well on the Tecsun, making CHU time beeps readable when nothing is audible in AM mode. (CHU suppresses the lower sideband, so use USB mode, not LSB.) With the PL-660 I can receive CHU on all frequencies (3330, 7850, and 14670) indoors with the whip antenna on an overland path of 1980 nm even with the present mediocre solar activity. Two of those frequencies (I forget which ones) use only 3 kw transmit power. Of course WWV is easy with this radio. One point in the Tecsun's favor as a time standard is that its signal path is all analog. If a radio has digital signal processing there can be a noticeable latency. That may be significant if you're using the radio as a gold standard to verify by eye and ear that a time display is dead beat with WWV. Or maybe you want to test how much delay you get on a phone connection to WWV or the USNO. The instruction book was obviously not written by a native English speaker. Sooner or later you'll figure out what it's trying to say. Happily, the radio is supplied with a set of precharged rechargeable cells. They're covered with Chinese writing and the only clue that they're rechargeable is the 1.2 V marking vs. 1.5 V for normal alkalines. You can use the latter, but remember to turn off the function that charges the cells when the AC adapter is active. The clock setting function is stupidly designed, I think. Hold the clock set button down until the hours flash. Use the tuning knob or keyboard to set hours. Press button again. Now the minutes flash. Set minutes. Press the Set button a third time to start the clock. So far, so good. But if you leave the minutes unchanged for more than three seconds, the clock starts itself! To hack the clock precisely, you must dither the minutes back and forth with the tuning knob until within three seconds of the tick. Then set the correct minute, and press the clock set button exactly on the tick. The radio feels solidly constructed, as good as the Sony in my opinion. Unlike the Sony, it's small enough to hold comfortably for many minutes at a time as you tune around for interesting signals. Though the user interface has some annoying quirks, remember, it's only a $110 radio.