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oldschool@tubes.com: May 27 12:55PM -0400 Although I used someone's frequency counter back around the 1970s, I never owned one. From what I recall, back then, there was a BNC connector on the unit, where test leads connected and were used to determine the frequency within a radio stage, or used to check the output from a signal generator.   I'm looking on Ebay and seeing some costly ones selling for $100 and up, which have lots of buttons and connectors. -OR- seeing some that are listed to go from 1 CPS to 70 or 80 MHZ, which tells me that they can show audio frequencies, and up to the 70 or 80 MHZ limit, which means they will work for AM radio, many Ham bands, CB radio, but *NOT* FM radio.   Then what caught my eye were these inexpensive handheld ones, such as: http://tinyurl.com/y84hun67   However, these do NOT have BNC connectors. Just an antenna. (No test lead connector), So, obviously, they can not read audio freqs, and can not be used to check the stage in a radio, but should probably pickup the output from a signal generator if the sig gen test leads are held near the antenna.   However, this device (above URL) only covers 50 MHZ to 2.4 GHZ. That means it's worthless for AM radio, CB radio, and many lower Ham bands. (In my case, this would be pretty useless, since I mostly work on radios that are AM FM CB or SWR.   Ideally, something that covered 1CPS to 110 MHZ would be best suited for my needs, but I cant find anything like that, at least not in the price range of $50 or less. (which is what I am willing to pay for something I wont get real much use from).   My antique Eico 320 Signal Gen only goes a little over 100 MHZ, so once again, the example URL I posted would not be real helpful.   So, I am pretty confused. What's better, an antenna or test leads?   Do they actually make and sell LOW PRICED Freq Counters that go from 1 CPS to 110 MHZ or so?   Then again, it almost appears that to get full coverage of all Frequencies, a person needs to buy TWO Freq counters, since UHF TV covers the 470 to 806 MHZ. But once again, what good is a Freq Counter with no test leads (just an antenna) for use on television?

Jeff Liebermann <jeffl@cruzio.com>: May 27 11:35AM -0700 On Sat, 27 May 2017 12:55:02 -0400, oldschool@tubes.com wrote:   Look for something that has a built in prescaler. Something like this: <http://www.ebay.com/itm/Blue-RF-Signal-Frequency-Counter-Cymometer-Tester-0-1-60MHz-20MHz-2400MHZ/172396798620> The basic counter goes from 100KHz to 60MHz. The other ranges use a prescaler to divide down the input frequency so that it ends up at less than 60MHz and can be counted.   Or, maybe one of these variations: <http://www.ebay.com/itm/Digital-6LED-1MHz-1000MHz-1GHz-RF-Signal-Frequency-Counter-Cymometer-Tester-G-/222009256193> <http://www.ebay.com/itm/1MHz-1200MHz-RF-Frequency-Counter-Tester-Digital-LED-METER-Cymometer-f-Ham-Radio-/331915125484> <http://www.ebay.com/itm/2016-0-91-OLED-RF-1Hz-2-4GHz-Frequency-Counter-Meter-Cymometer-Tester-/172692754650>   You can also use a mixer to take a higher frequency signal, and mix it down to something lower that the counter can handle. I have some HP microwave counters that work like that.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

mike <ham789@netzero.net>: May 27 11:52AM -0700 > Frequencies, a person needs to buy TWO Freq counters, since UHF TV > covers the 470 to 806 MHZ. But once again, what good is a Freq Counter > with no test leads (just an antenna) for use on television?   What good is a frequency counter WITH test leads for television. Where are you gonna connect those leads and what's the signal level there? And how do you measure channel 40 when channel 42 is 10x stronger.   You suffer from test equipment buyer's exaggeration. "I dunno what I want so gimme EVERYTHING, and then some, for cheap."   Take a step back and decide what you need to measure that you didn't need for the last 50 years.   I designed frequency counters for a living back in the day. I have more than a few. I haven't turned one on in more than a decade, and here's why...   FOR CHEAP COUNTERS: They're inaccurate. If you're setting a radio frequency, you want an ACCURATE counter. Most other times, the accuracy is irrelevant. It's go/nogo. The accuracy and stability of the timebase may be the most important parameter. What do you want to do?   They're insensitive. You typically can't go probing around in equipment and learn anything. A counter typically reads the biggest signal it hears. You might find that everything reads 120Hz. Probing around in a radio circuit may detune it. What do you want to do?   I find an oscilloscope to be a more useful tool. You can read the frequency right off the screen with sufficient precision for most troubleshooting tasks. And you can do it in the presence of noise that might render a counter useless.   Expensive counters have a few bucks worth of counting stuff. The majority of the expense is in the timebase and the front end that helps you trigger on what you want to observe. All those knobs are there for a reason.   If you need more accuracy, you probably need a LOT more accuracy.   Draw a frequency chart from 0 to 2.4 GHz. Put an arrow at every frequency where you ever needed to measure a frequency and the specs of the counter you'd have needed to do it. Let that be your guide. You might decide that you still don't need a counter that you can afford. ;-)   You can do audio with a cellphone app. Just be careful what you plug into that microphone jack.   This seems to be closer to what you want. EBAY ID 401196543325 If it has a removable antenna with signal and ground connections, you can make test leads. Just be careful with DC or too much signal breaking it.

Clifford Heath <no.spam@please.net>: May 28 08:09AM +1000 On 28/05/17 04:35, Jeff Liebermann wrote: > The basic counter goes from 100KHz to 60MHz. The other ranges use a > prescaler to divide down the input frequency so that it ends up at > less than 60MHz and can be counted.   I have two of those. I bought the second because I thought I'd broken the first, it performed so badly. They're as bad as each other.   If you have a strong and stable signal, it can work ok, but the input design is poor. The HF and the pre-scaler both have dual-gate mosfets, but there's no gain control (automatic or otherwise) and the inputs are paralleled. I've disconnected the two inputs by cutting a track and soldered on a little bit of RG-158 to an SMA connector for the high range.   I'd love it if Mike is willing to share some of his counter front-end wisdom.

Michael Black <et472@ncf.ca>: May 27 07:24PM -0400

Phil Allison <pallison49@gmail.com>: May 27 06:25PM -0700 mike wrote:   > why...   > FOR CHEAP COUNTERS: > They're inaccurate.   ** Anything using a crystal time base will have good accuracy.     > What do you want to do?   > They're insensitive. > You typically can't go probing around in equipment and learn anything.   ** Yep, RF circuits are very load sensitive and you will need a FET probe to buffer the signal.   But any counter will read the carrier frequency of a transmitter, long as it has a few milliwatts of output.   Radio mics operating in the VHF and UHF bands can be read by placing them close to a short antenna attached to the BNC input.   Analogue mobile phones (remember them) would read from 5 yards away.       ..... Phil

rickman <gnuarm@gmail.com>: May 27 09:41PM -0400 Michael Black wrote on 5/27/2017 7:24 PM: > seems out of fashion now, so the prescalers are meant for other things, and > offer a binary division, so bypassing it in the counter (and maybe adding an > input stage) means the clock for the counter is "wrong".   I don't think the prescaler is the problem is it? The problem is the inappropriate front end. If you design a decent front end and feed the prescaler with that signal it should work at lower frequencies ok. It may not have timing controls to let you measure below some 10s of Hz or so, but is that really a problem? Or do the prescalers work in some way I'm not familiar with so they just don't operate at lower frequencies?   --   Rick C

mike <ham789@netzero.net>: May 27 07:20PM -0700 On 5/27/2017 6:25 PM, Phil Allison wrote:     > ** Anything using a crystal time base will have good accuracy.   > ..... Phil   I don't expect anything I could say would change your mind. We'll just have to disagree on that.

Phil Allison <pallison49@gmail.com>: May 27 07:58PM -0700 mike wrote:   ---------------     > > ** Anything using a crystal time base will have good accuracy.   > I don't expect anything I could say would change your mind.   ** Why I change my mind when what I posted is correct ??     > We'll just have to disagree on that.     ** You must enjoy being wrong.   You have nothing that explains your strange opinion ?         .... Phil

Jeff Liebermann <jeffl@cruzio.com>: May 27 09:25PM -0700 On Sun, 28 May 2017 08:09:04 +1000, Clifford Heath   >I have two of those. I bought the second because I thought I'd >broken the first, it performed so badly. They're as bad as each >other.   Thanks. I was thinking of buying some of those. I should have known as much of the low cost "modules" that I've purchased seem to have deficiencies as a result of crude design or cost cutting exercises.   To clarify my my comments a little, I was not recommending the purchase of any of the devices I pointed to on eBay. I meant them as examples of devices that have prescalers, which was part of the OP's rant on requiring multiple counters to cover the frequency range. My comment "Something like this:" usually preceeds something that I haven't worked with.   >or otherwise) and the inputs are paralleled. I've disconnected >the two inputs by cutting a track and soldered on a little bit >of RG-158 to an SMA connector for the high range.   I picked that particular example because it has a drawing of the PCB showing i/o and controls: <http://i.ebayimg.com/images/g/hBYAAOSwAPVZGlOn/s-l1600.jpg> It has two adjustments labelled "High channel sensitivity adjust" which I guess would help with the tiggering. Do these controls work, or were they deleted in yet another cost cutting exercise?   >I'd love it if Mike is willing to share some of his counter >front-end wisdom.   The OP has not disclosed how he plans to use the counter. If it's a bench instrument, that requires precision, I suggest any of the numerous used HP counters available on eBay. <https://www.google.com/search?tbm=isch&q=hp+universal+counter> Especially the HP 5300 series: <https://www.google.com/search?q=hp+5300+counter&tbm=isch> I have accumulated a fair collection of these and find that used counters are a far better deal than the eBay instruments, such as: <http://www.ebay.com/itm/Victor-VC3165-Radio-Frequency-Counter-RF-Meter-0-01Hz-2-4GHz-K8M3/122448388056>   Incidentally, since the OP is into tubes, my favorite counter is an HP 5248M with genuine Nixie tubes. Middle right above the spectrum analyzer: <http://802.11junk.com/jeffl/pics/home/slides/lab.html> The pile of 4 plugins under the Glad bag box are the various mixer type downconverters I previously mentioned. I also have an HP 5245L: <https://www.eevblog.com/forum/repair/repair-of-hp-5245l-nixie-frequency-counter/?action=dlattach;attach=204375;image> Cheap but scarce on eBay: <http://www.ebay.com/itm/HP-Hewlett-Packard-5248L-Electronic-Counter-5254C-Frequency-Converter-15-3-0GHz-/182520538437>       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Clifford Heath <no.spam@please.net>: May 28 04:13PM +1000 On 28/05/17 14:25, Jeff Liebermann wrote: > Thanks. I was thinking of buying some of those. I should have known > as much of the low cost "modules" that I've purchased seem to have > deficiencies as a result of crude design or cost cutting exercises.   It was developed by a good hobbyist who posted everything online.   I think that full schematics of slightly earlier versions are available online. He uses a dual-gate MOSFET before the prescaler and before the main counter, with the inputs paralleled. I think that affects the sensitivity (though I don't have measurements) so for my 2nd module, I cut a track to separate the input paths. I might wind up adding an independent input amplifier with AGC, or even a pot to adjust the 2nd gate bias on the MOSFETs for a manual gain control. A little difficult though, as parts of the circuit are underneath the LED displays, so I'd need to remove those.   The main counter is a PIC.

oldschool@tubes.com: May 27 08:10PM -0400 Of all the stupid things . . . . While looking at some online manuals, I downloaded a .PDF manual that's upside down.....   What the hell am I supposed to do, stand on my head to read it?   I have the software to flip graphics, but I dont have the slightest clue how to flip a PDF file.   Dont people check this stuff before they post it?   (No, I dont have a printer. I read everything on screen, so I have never seen the need to waste paper or own a printer).   I guess I'll have to take this one to a print shop if I want to read it.

Jon Elson <elson@pico-systems.com>: May 27 08:22PM -0500 > (No, I dont have a printer. I read everything on screen, so I have never > seen the need to waste paper or own a printer).   > I guess I'll have to take this one to a print shop if I want to read it. I guess you can turn your monitor upside down!   Jon

thekmanrocks@gmail.com: May 27 06:27PM -0700 Not to spoon feed ya, but most recent versions of Adobe Acrobat reader should have a rotate function. Ctrl+R, and equivalent command on Macs.

rickman <gnuarm@gmail.com>: May 27 09:37PM -0400 > reader should have a rotate > function. Ctrl+R, and equivalent > command on Macs.   There is a reason why he likes tube equipment.   I had my oscilloscope open once to fix a problem and on a whim I decided to swap the connections for the horizontal sweep. Don't know why, I just did. Now I'm very used to it. If I were to want to share any photographs of traces I would have to reverse the image for anyone else to look at... not that it would be likely this is needed.   --   Rick C

analogdial <analogdial@mail.com>: May 28 03:43AM > While looking at some online manuals, I downloaded a .PDF manual that's > upside down.....   > What the hell am I supposed to do, stand on my head to read it?   Yes, that would work. The suggestion to turn your monitor upside down is also good. If you have a mirror or two, you could flip the image with them. Failing that, you could have your eyeballs surgically inverted.     > I have the software to flip graphics, but I dont have the slightest clue > how to flip a PDF file.   It's almost impossible on my PDF viewer. I can either drop a menu by clicking on some stupid icon which might look something like a dog eared piece of paper and then clicking on the words "rotate right" or "rotate left". Why did they make it so obscure and why did they give me too many choices? Probably programmed by damn kids who have no respect for their elders, that's why.   Then, to add to the confusion, I can rotate images without the menu by pressing on the Ctrl key and the right arrow key OR pressing on the Ctrl key and the LEFT arrow key. Whew!!     > Dont people check this stuff before they post it?   What else would you expect with today's failing education system and the "everyone gets a trophy" attitude? They're just raising kids to be selfish and idiotic.     > (No, I dont have a printer. I read everything on screen, so I have never > seen the need to waste paper or own a printer).   > I guess I'll have to take this one to a print shop if I want to read it.   That works, too.

Jeff Liebermann <jeffl@cruzio.com>: May 27 09:36PM -0700 >While looking at some online manuals, I downloaded a .PDF manual that's >upside down..... >What the hell am I supposed to do, stand on my head to read it?   Most PDF viewers will rotate pages. Older versions of Adobe Acrobat Viewer will not. I use PDF-Xchange viewer and editor programs instead of Acrobat: <https://www.tracker-software.com/product/pdf-xchange-viewer> How to rotate pages: <http://help.tracker-software.com/pdfxe6/index.html?rotate-pages_ed.html>   You can also rotate documents online: <https://www.pdfrotate.com> Click on "Rotate Single Page Instead" and then "More" as needed.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: May 27 09:48PM -0700 On Sat, 27 May 2017 21:36:37 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   ><https://www.tracker-software.com/product/pdf-xchange-viewer> >How to rotate pages: ><http://help.tracker-software.com/pdfxe6/index.html?rotate-pages_ed.html>   Oops. You want Editor, not Viewer: <https://www.tracker-software.com/product/pdf-xchange-editor> Despite the pricing, the trial version of Editor will continue to work after the trial period is over and retains a limited but useful subset of the editing features (including page rotation).   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

rickman <gnuarm@gmail.com>: May 28 01:16AM -0400 analogdial wrote on 5/27/2017 11:43 PM: >> seen the need to waste paper or own a printer).   >> I guess I'll have to take this one to a print shop if I want to read it.   > That works, too.   I didn't think of that. But you'll have to get the person at the print shop to make sure the copies are made upside down or it will just be the same problem.   --   Rick C

rickman <gnuarm@gmail.com>: May 28 01:21AM -0400 Jeff Liebermann wrote on 5/28/2017 12:36 AM:   > You can also rotate documents online: > <https://www.pdfrotate.com> > Click on "Rotate Single Page Instead" and then "More" as needed.   I recall many years ago, before we all had computers on our desks, we had a small room with a couple of computers for everyone to share. One of the secretaries was learning to use a small Mac, the one they drew in cartoons. She knew nothing of how a mouse worked and was just learning to use the machine. She asked someone what to do when the mouse hit the side of the computer and the cursor wasn't where you wanted it.   The guy telling the story was laughing at her. I felt bad for her. She was a very nice person, but didn't understand the world of engineers much less engineering. That wasn't her fault. Engineers can be very stupid when dealing with people.   --   Rick C

thekmanrocks@gmail.com: May 27 03:38PM -0700 ohg.. wrote: "But go to any store that has a hundred TVs running. The one cranked to stupidity is the one most people will think has the best picture. Kind of like the old "sizzle and boom" EQ settings people like to adjust their stereos for. "   LOL!   I wonder if this is the case in stores in countries outside the U.S. I know it was in one electronic emporium in the Philippines. I eyeballed a 4K OLED to sane levels as you did, but within 5 minutes of turning my back the sales staff had the set back in torch mode!   No WONDER consumers have no concept of accuracy when it comes to a TV picture, and manufacturers are largely to blame.

oldschool@tubes.com: May 27 01:11PM -0400 On Fri, 26 May 2017 20:44:23 -0400, "(PeteCresswell)" <x@y.Invalid> wrote:     >Does anybody know enough about LED lights in general to ballpark the >problem? Not knowing anything, I tend to think it's the screw-on >switch/back of the light.   Someone once handed me one of those cheap $5 or less LED flashlights, and said "What's wrong with this thing?". I took a look. When the switch was turned ON, it worked fine and was bright. When the switch was turned to the OFF position, the LEDs were still lit, but extremely dim.   I have to admit, I was puzzled. I ripped it apart as much as possible. Icould not find any reason. I could only figure that there was some sort of resistance leaking across that switch, but I did not have a multimeter on hand. Plus the switch could not be removed without destroying the flashlight.   I just told the owner to remove the batteries when they are not using it.   On the other hand, I own at least a dozen of those (similar) cheap LED flashlights sold by Walmart for $1. I have no complaints. They work fine, and for the price they are worth buying. The only bad thing is that it costs $1 (or more) to replace the three AAA batteries, so it's ofter cheaper to just buy another flashlight (they come with batteries).   However, "Dollar Tree" has a 4 pack of AAA batts for $1, so that only costs 75 cents for replacement batteries....

tabbypurr@gmail.com: May 27 11:46AM -0700 > ofter cheaper to just buy another flashlight (they come with batteries).   > However, "Dollar Tree" has a 4 pack of AAA batts for $1, so that only > costs 75 cents for replacement batteries....   use rechargeables.     NT

oldschool@tubes.com: May 27 01:25PM -0400 On Sun, 21 May 2017 23:18:20 -0700, John Robertson <spam@flippers.com> wrote:     >I hate having to replace plugs/sockets after four or five years because >I cheaped out when I repaired it previously...   >John :-#(#   In 50 years, I have never had to replace a RCA audio jack on anything, with the exception of once overheating it while soldering and melting he insulation inside of it. (That was when I was young and using a much too large soldering iron).   There is nothing wrong with RCA plugs/jacks. If they get a little corroded from being in a bad environment, a little 2000 grit sandpaper cleans them right up. (Or even a pencil eraser).

oldschool@tubes.com: May 27 01:19PM -0400 On Thu, 25 May 2017 19:39:59 -0500, "Dave M" <dgminala@mediacombb.net> wrote:   >That would go a long way toward insuring that the manuals would survive for >a reasonably long time (maybe outliving the site owners).   >Dave M     Although it's possible, I dont have a website. Back in the 90's anyone could make a simple HTML website, but these days that's no longer possible.   Plus, since I am on dialup, I much prefer just storing data on my own computer. I have 1TB of storage space, so it's a lot easier to have it right here at home.   Heck, just this week, I went to a WIFI and downloaded 140 episodes of one of my favorite old 1960s TV series (from youtube). It took me about 7 hours of downloading, and ended up being around 22GB. But now I can watch these anytime anywhere.   That's not real possible with these sites that require a person to go thru multiple stems and enter a Captcha, for each download.

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