I first saw the meter at the ARRL SW Convention in 1995 (on the Queen
Mary). I remember the Radio Shack booth and picking up info on the
meter and the "new" 2m mobile rig. Looked interesting at the time and I
picked one up a few months later for $79.
I sent the following e-mail to someone last January. I'm forwarding it
here due to interest in the meter...
- Aaron
**************************
> Lawrence,
>
> I picked one up a year ago and it's been collecting dust ever since.
> For the $$$, it's a pretty decent unit, but it does have a couple of
> problems...
>
> - Peak hold time is too short for CW or SSB. It was obviously timed
> for constant carrier applications. You'll get a reading, but you need
> to be quick to read it. If you're doing 13+ WPM on CW, then it should
> hold long enough.
>
> - The connector for the remote sensor is NOT weatherproofed nor does
> it look like it was designed to be. Just tape it up well or use lots
> of putty sealant or silicone.
>
> There were also a couple of other "minor" problems, but I don't
> remember what they were. On sale for $59, it's not really a bad
> deal...sorta like their DSP (had one of those too...until I tried
> transmitting at more than 10 watts HF... not very well shielded at
> all! Got a Timewave instead).
>
> A while back, one of the design engineers of the unit appeared on one
> of the HAM usenet or mail reflector groups. He asked for opinions of
> the unit and I had a BUNCH of questions for him. I wish I saved that
> mail, but I do have some of his responses. I've included them below.
> Basically, I asked what the accuracy would be above HF (seems pretty
> good on 6M) and if there were any mods possible with the unit (to
> increase peak hold time). Accuracy was based on freq and power levels
> and the firmware was masked on a custom ROM, no mods possible. You
> might want to e-mail him and ask his opinion of the unit.
>
> Try it for $59. If you don't like it, return it on the 30-day return
> policy. Couldn't hurt!
>
> 73!
>
> - Aaron Hsu, KD6DAE
> athsu@unistudios.com
> dae@pacbell.net
>
>
> ps. Below is e-mail from Doug, the engineer...
>
> -----------------------
>
> Actually, we did test this with SSB before code release. We left it
> as RS
> OK'd it. Looking back it would have probably been a good idea to field
> test
> this with lots of hams to get more comments before we went to
> production.
> Unfortunately, we never did this really for any product our group
> designed,
> RS always had really tight schedules to be able to meet catalog
> release.
>
> Thanks for the feedback. I am wondering what's on the addendum since
> it was
> obviously released after I left in December.
>
> Regards,
>
> Doug
> KA8CTL
>
> --------------------------
>
> ALL of the timing for the meter is done in software, so there is
> really no
> way to change to peak hold time. I kept changing the timing until
> Radio
> Shack Engineering OK'd what they liked. Unfortunately it beginning to
> look
> like quite a few hams don't like it. I wish I could could offer a
> software
> fix, but the micro is a masked Samsung part and there are no
> one-time-programmables available.
>
> I don't know what the power accuracy is at 2 or 6 M. We only had
> equipment
> when I was at Tandy to check this over the HF bands.
>
> Althought the power accuracy is spec'd at 10% of full scale this isn't
> really
> the best the meter can do. The meter is calibrated at 1, 5, 10, 100,
> 500,
> and 1000 W in both the forward and reverse directions at the factory.
> This is
> stored in EEPROM and then used to interpolate the power reading during
> normal
> use. What this means is that the accuracy is pretty much as good as
> the
> calibration (at those points). If you were to calibrate using a 1%
> reference
> meter, you could probably get the overall accuracy at those points
> down to
> 3-5%. The accuracy in between would be a little higher. Unfortunately
> getting that good of a reference meter is really difficult. Just for
> reference, we looked at the $199 Daiwa meters and they were spec'd at
> 12%
> worst case. I won't tell you how bad the other RS wattmeters really
> are over
> the HF bands.
>
> Hope all this was helpful (or at least informative).
>
> Doug
> KA8CTL
>
>
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