On Wed, 15 Jun 2005 09:10:40 -0400, Vinnie S.
wrote:
On Wed, 15 Jun 2005 06:48:24 -0400, Dave Hall wrote:
Dave,
Do you recomend a decent Freq counter I can get on ebay for aound $40? They
have a ton of older HP and BK Precisions. I had a Fluke 1900A, but it died on
me, and I am looking to replace it.
Well, as a matter of course, you get what you pay for. To me $40 is in
the "recreational user" category. For true lab precision quality test
equipment, you're going to pay a lot more (Unless, of course, it's 30+
years old, and then I'd have my doubts about calibration).
Well, most of these are bench quality that have been removed from labs that have
been shut down. For how often I have to do it, it doesn't pay to buy a $200
counter when it's going back in the closet after alignment.
Like I said before, accuracy costs money. How accurate do you want to
be?
I have a Fluke counter, which I obtained about 8 years ago. At the
time I got it, the calibration was about a year old. While the
optional heated crystal oven high precision timebase is fairly stable,
I'm sure there's been some drift in the last 8 or 9 years.
So even if you get a "Lab quality" counter, unless the seller can
provide calibration traceability, you still don't know how accurate it
might be.
I used to do calibrations, years ago on research instruments that was traceable
to NIST, and NBS before that. At that time, traceability was at least $100 per
piece. I don't see how it would be cost effective to get a counter with this
traceability that could easily run you twice the cost of a new radio.
I was going to bring that up. The cost of calibration is often more
than what you paid for the used instrument itself, unless you have
access to a cal lab and can do it yourself. Once in a while I'll sneak
one or two of my pieces into the pile at work when we send a bunch out
to cal. But the bottom line here is that it makes little sense to buy
a lab quality counter for its inherent accuracy, and not have it
recently calibrated.
But these are the issues you have to face. If you want something that
is "Dead on, no argument, last word on the subject" accurate, you will
have to pay for it. If, on the other hand, you are content with being
"close", a $40 counter will fit the bill. The choice is yours.
I get a kick out of guys on the air (SSB) arguing over who's on
frequency and who isn't. One guy will tell another to tune to him
because he's "a bit off". The other guy will respond that if there's a
difference, it must be the first guy's radio, because his "XYZ brand"
is "dead on", and it goes from there.
In the grand scheme of things, does it really matter? As long as
everyone has the ability to synchronize their transmit with their
receive clarifier, and can tune to each other, where exactly they are
becomes irrelevant.
But you can see how the wide variation of quality test equipment and
radio drift can make it nearly impossible to bring everyone's transmit
frequency to the same exact point (Within 100 hz). That's why I don't
like "locked on" transmit clarifiers.
Dave
"Sandbagger"
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