universal frequency counter

On a sunny day (Tue, 12 Oct 2010 17:43:40 -0700) it happened John Larkin wrote in :

Hell, maybe you have an intern who could design the 10X prescaler, and use my RS232 in a connector shell frequency counter:

What would it cost you? 20 $? You probably have the prescaler chips already. And it would be nice study project for your layouter ! One should start with a simple RF board layout by hand with PCB (that is a Linux program BTW).

But it would not impress the CEO from BigX company when he walks into your shop. So then it must be image you want, Simple, get the biggest most complicated box you can find from ebay, does not matter if it works, as long as it looks good. My 10$ worth.

On a sunny day (Wed, 13 Oct 2010 01:10:35 -0700) it happened Robert Baer wrote in :

I love this. Lucky taxes are not that weird here, you can just write it of in a few years.

. .

We bought low-end Protek function generator becasue it was the only one we could find (cheap) that had resolution below 0.1 Hz. I was OK, but had some weirdness too. The display had more resolution than the output... you can change the displayed frequency, but the output frequency would not change at all! And then make a 'big' jump to some new frequency. (Hard to know exactly what frequency you were getting) When compared to another generator the protek seemed to 'miss a beat' once a second or so. (Like it couldn't update the display and count clock pulses at the same time.)

The cheap protek counter we have does some unknown weird stuff when it's looking at pulses. It seems to display the average of two readings... but not always. There is something going on in the software, but no documentation.

Perhaps try something not quite so low-end. We have some GW-Instek gear that is OK.

(Hey Dave Jones, you should do a review of cheap test gear other than DMM's. How about counters or generators?)

George H.

simple RF

What I'd like on my bench is a universal counter, with A and B channels, each with adjustable trigger level and slope, time A:B measurement, period averaging, frequency ratio, all that "universal" stuff. Why spend months doing it myself when I can buy it for $400?

We rarely host BigX CEOs, and they wouldn't be impressed by a frequency counter, homebrew or not. They do tend to like the conference room, which is mostly glass and has nice views. I designed it myself.

I actually have a Wavecrest, a huge $100K counter with 1 ps resolution. Big heavy rackmount thing, black, sorta ugly, silly design. I got it on ebay for a couple of hundred dollars. It's down in my dungeon.

John

I am shocked, shocked! at this suggestion.

John

"Write down" means expense over time, which lowers taxable income over some number of years, if you are running at a profit. You don't get the equipment for free. In the US, we can immediately expense (not depreciate) up to around $100K a year of capital expenses if we choose to. That amounts to roughly a 30% effective discount if you're profitable, no discount if you're not.

We're losing money this year, on purpose, and we're net getting tax money *back* from the feds.

I'm not bitter and twisted, and I could move to Nevada or Mississippi if I wanted to. We're doing fine and having fun. It's the middle-class worker-guys and urban kids who really get hurt by our government's insane anti-business policies. Which policies kill jobs and reduce tax revenue, requiring that same governmant to borrow money it doesn't have for job-creation stimulus that doesn't work.

John

John Fields wrote in news: snipped-for-privacy@4ax.com:

every counter should have a TXCO.

TEK will just buy some Taiwanese product and rebadge it. that's what they have been doing. I don't believe TEK has any DMM/counter/generator engineeers any more. Just scopes.

their production is moving to China anyways.

--
Jim Yanik
jyanik
at
localnet
dot com

Interesting. The Protek counter does look complex. We have one digital function generator here that nobody can get to work; the menus make no sense at all.

I recently bought a Rigol digital scope and a B&K analog function generator, both very nice, sensible boxes. And a B&K USB device programmer, also very nice.

John

You move out of San Fransicko. Better yet, move out of Californica.

Heard an interesting statistic yesterday... folks are abandoning Californica and moving to Oklahoma. How's that for WILD! ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
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| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
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               I can see November from my house :-)

Don't be an idiot, as much as you seem to enjoy it.

John

I bought a Wellon (Chinese) EPROM (etc.) programmer off of eBay a bit over a month ago, and for ~$125 shipped was quite surprised just how good both the software and hardware are. This is it:

... probably 10x the bang-for-the-buck compared to a Xeltek Unipro I bought for something like $500 some ~15 years ago now. (In fact... I think it was purchased from someone advertising it here on Usenet...)

---Joel

Agreed. But $780 is a bit much. We buy TCXOs for $25, OCXOs for $80. I'm sure Agilent gets better pricing. They want $1100 for the OCXO option. We charge $210 and $400 for OCXO options on two of our products.

TCXOs have good frequency stability, but the thermal time constants of the sensor and the crystal usually don't match, so they have mediocre close-in phase noise and thermal transient recovery. Packing one in a bit of foam greatly improves both.

John

...

...

I don't want to totally dis the Protek function generator. In some ways it's very nice. It has all sorts of different outputs, Burst mode, noise, and some other things. None is very well documented though.

George H.

--
Geez, John, It wasn't me bitching about paying $1150 for a $10
prescaler, so if you can do it in-house for 10 bucks and you don't,
well, who's the idiot then?

I tried using a low-cost freq. 550MHz counter a while ago and I found the sensitivity at high frequencies (still within the specified range!) was so poor I couldn't use it. Maybe the 'real deal' does better.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
--------------------------------------------------------------

This really is the graziest tax I've ever heard about. US citizens should really quit bitching about taxes in Europe :-)

Anyway, you don't have to wait long for equipment to depreciate. If you want to send money down the drain really fast, buy new test equipment. Burning the money is still slower :-)

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
--------------------------------------------------------------

You, obviously.

John

--
Failsafe to fuckhead mode, huh?

You wear it well.

Tek does offer benchtop DVMs, but they sure look like Flukes. The last Fluke I bought (8845A, very nice) was made in the USA. It replaced the dreadful Chinese Keithleys that I sent back.

John