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"pfjw@aol.com" <pfjw@aol.com>: Mar 13 05:31AM -0700 On Sunday, March 12, 2017 at 7:26:18 PM UTC-4, Trevor Wilson wrote:   > **YIKES! First, you got stuck with George W and now, Trump. Can it get > any worse for the US?   Sure. Trump gets impeached and we get Spence. During the entire W reign, many prayed for his continuing good health - the alternative was Cheney. There is a difference between a small-minded buffoon and a clever psychopath.   But you need to keep in mind that WE THE PEOPLE get exactly and entirely what we deserve as we vote these idiots into office time after time after time - and then we let them do as they please without any sorts of controls or consequences.   Keep in mind that the president is still and largely a figurehead. Congress makes the laws - and could at any time whatsoever eliminate, reduce or dissipate "executive privilege". But the blame-game makes that too convenient to do.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Mar 13 09:42AM -0700 These entire thread is somewhat naive at the least.   Australia Cambodia Chile Taiwan Cook Islands Costa Rica Croatia Cuba Czech Dominican Faroe Islands France Haiti Iceland North Korea South Korea Laos Liberia Luxembourg Malaysia Nepal Netherlands New Zealand Norway Panama Paraguay Philippines   Russia   Schleswig-Holstein Serbia Sint Maarten Slovakia Slovenia Thailand United Kingdom United States   All use Red White and Blue as their national (State) colors.   NOTE: Russia is in this number as well.   Funny thing: Starting around 1938, European politics started moving distinctly to the right. And, much of Europe started appeasing a dictator to the east. We all know how that turned out, although some few are in denial or would like to be.   Today, US & AND European politics are moving distinctly to the right, and we are busy appeasing a dictator to the east.   "Those who cannot remember the past are condemned to repeat it." George Santayana, 1905   Peter Wieck Melrose Park, PA

oldschool@tubes.com: Mar 13 02:26AM -0600 I've been looking into buying an Audio Generator (Sine and Square Wave). I mainly want this to run thru an amplifier to listen to the frequency repsonse of the amp and speakers. Nothing very scientific, just to see what these amps and speakers can do.... And on occasion to inject an audio signal into amp sections to dee if the audio is passing that stage.   Originally I was looking at some of the old tube gear, such as the Eico model 377. I also looked at the Heathkit IG-18 a transistorized version from the 70s. Because I like that old test gear, I'd be happy to get either of these, or another similar. Both of these are Sine and Suqare Wave. But what I am finding is the prices combined with high S+H fees, make these things very costly, and I have not found any of them which claim to work. Sold as-is, for parts or repair. So, I may end up paying $60 or more and getting something that dont work, likely needs new caps, and so on..... If they were $25 or less, I'd take a chance, but not for that kind of money.   My search on ebay lead me to something called a "Function Generator". What the heck is that??? And also called a DDS device. (I have no clue what DDS means). But I carefully looked at this NEW device, sold without a box (case), but only needs a power module and test leads. They sell for around $14 from China, but since I dont care to order from China, I'll probably have to hunt one down from the US, and pay around $5 or $10 more. But that's ok. These have both the Sine and Square wave, as well as Triangle wave (what does that sound like?).   While I prefer the older stuff, for around $20 a cheap wal-wart, and a little work putting it into a box, I'd probably buy one of these, *IF* it will do what I need..... I have read all the info on the ebay pages, but I am not 100% sure that this is a modern replacement for the old audio generators. One nice thing, is that they will show the exact frequency on the digital readout.   IS THIS WHAT I AM LOOKING FOR? Is something like this made to really be used, or is it just another toy that does little and fails in a few months?   And can something like this work to test tube amps, without blowing up from the high voltages in tube gear?   One last thing that has me puzzled. There are two BNC connectors. One is labeled DDS, tho other is HS.   I found this in the description. DDS frequency range: 1Hz-65534Hz, high-speed frequency (HS) output up to 8MHz.   I dont understand how or what the high speed feature does. Why would an audio frequency be or need "high speed"? And what is the point for this device to go above 20,000 cps, since we cant hear that anyhow? Going up to 8MHZ seens senseless, unless this also serves as a RF signal generator.   Here is the ebay URL.   http://tinyurl.com/h5celuc

Colin Horsley <horsley-spam@westnet.com.au>: Mar 13 08:20PM +1100 > My search on ebay lead me to something called a "Function Generator". > What the heck is that??? And also called a DDS device. (I have no clue > what DDS means).   https://en.wikipedia.org/wiki/Direct_digital_synthesizer   Col     --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Jasen Betts <jasen@xnet.co.nz>: Mar 13 09:32AM > what these amps and speakers can do.... And on occasion to inject an > audio signal into amp sections to dee if the audio is passing that > stage.   Any reason you've not looked at PC software?   > My search on ebay lead me to something called a "Function Generator". > What the heck is that??? And also called a DDS device. (I have no clue > what DDS means).   look it up on wikipedia. it means that inside there's some sort of computer generating a digital wavform, that gets converted and comes out the output   > I'll probably have to hunt one down from the US, and pay around $5 or > $10 more. But that's ok. These have both the Sine and Square wave, as > well as Triangle wave (what does that sound like?).   you can probably buy he same thing from china on ebay, for about the same price, most large scale vendors are present in multiple marketplaces.   > IS THIS WHAT I AM LOOKING FOR? > Is something like this made to really be used, or is it just another toy > that does little and fails in a few months?   it will probably last longer than a few months, especially if you put it in a good case.   > device to go above 20,000 cps, since we cant hear that anyhow? Going up > to 8MHZ seens senseless, unless this also serves as a RF signal > generator.   it's probably a square wave at 128 times the DDS output frequency. it might be useful for other purposes   -- This email has not been checked by half-arsed antivirus software

Ralph Mowery <rmowery28146@earthlink.net>: Mar 13 10:13AM -0400 In article <vaicccta9pdjea9abbc1074l06705f6677@4ax.com>, oldschool@tubes.com says... > $60 or more and getting something that dont work, likely needs new caps, > and so on..... If they were $25 or less, I'd take a chance, but not for > that kind of money.   For the price you might as well get a function generator. Most of the audio type signal generators put out sine waves and some square waves. The function generator can put out those and many other waveformes. I have one of the China function generators that lets me hook it to a computer and any kind of waveform I can draw on the computer screen, the generator will put out.   The one I have will go from below audio to about 25 MHz. They make some other models that only o to about 6 MHz for a few dollars less. It is dual chanel so you can put signals into a stereo if you want to. Each chanel can be set sperate. It includes a frequency counter so you can input a frequency and see what it is. I am not sure how accurate it is above the audio range. There is no difference in audio and RF as far as to what you get out, just the range of frequencies, so you can use it as an rf signal generator if you want. They are not shielded being in a plastic case.   The waves other than a sine wave starts to degrade above about 1 MHz. There is a modification that is on youtube that I made to mine to help that out. You probably would not want to try that as it involves changing about 6 or 8 of the SMDs, but the parts were less than $ 20 from one of the larger companies. I did it mainly to see how it would work and am learning how to work with the SMDs.   There are some vidios on youtube about this one and probably others.   http://www.ebay.com/itm/DDS-Dual-channel-Signal-Source-Generator- Arbitrary-Waveform-200MSa-s-25MHz-W9U7-/162074779152? hash=item25bc68de10:g:CwgAAOSw74FXOayX

"pfjw@aol.com" <pfjw@aol.com>: Mar 13 07:54AM -0700 You can get a CD, tape or vinyl record that will do this, and it will also test the reproducer at the same time.   http://www.soundstagedirect.com/analogue-productions-the-ultimate-analogue-test-lp-180-gram-vinyl-records.shtml?gclid=Cj0KEQjwhpnGBRDKpY-My9rdutABEiQAWNcslAdJZ8Oa_AoFf0E003jJYsI8x2OYXqe8Pxxv4cGi8cUaAiwd8P8HAQ   https://www.amazon.com/Stereophile-Test-CD-Compact-Disc/dp/B00008FUKK   http://www.gennlab.com/alignment_cassettes.html   http://usrecordingmedia.com/ancaltap.html   A function generator will be of use combined with a scope so that you can observe "before" and "after", but as a simple source of sound, not so much considering the real-estate it requires (Chinese chip devices excepted). However, if you do intend to get a (good) scope, then by all means a function generator is useful for several reasons.   Note that some very good frequency generators operate both in AF and RF. Look for one of those unless you truly *WANT* a function generator. It won't be cheap for a good one, but it does put it all in one box. Or, you could go for the gold and get one that also has a waveform function - more money, but more utility as well.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Mar 13 09:27AM -0700 >I mainly want this to run thru an amplifier to listen to the frequency >repsonse of the amp and speakers. >Here is the ebay URL. (...) >http://tinyurl.com/h5celuc   That DDS generator only goes up to 65KHz, does not have a built in frequency sweep feature, and does not have a sawtooth output or built in detector suitable for displaying a frequency sweep on an oscilloscope. To sweep an audio amplifier with a DDS, you will need a sine wave generator feature, and an up/down counter or frequency modulator to sweep the frequency range.   First look at a real function generator. Next, build a checklist of the features you need. Then, go shopping using the feature list. You're doing this backwards.   Note: You can use a PC sound card as a swept audio source and function generator: <http://www.daqarta.com/dw_gen.htm> <http://www.instructables.com/id/PC-Sound-Card-Signal-Generator-Interface/?ALLSTEPS> etc...   Most of the PC based oscilloscope and spectrum analyzer programs have built in generators. I use Visual Analyzer: <http://www.sillanumsoft.org/prod01.htm> and Spectrum Lab: <http://www.qsl.net/dl4yhf/spectra1.html> Both have built in generator functions, including two tones for intermodulation measurements.   This scope program has a tolerable white/pink noise generator. <https://www.zeitnitz.eu/scope_en>   Hint: Buy a higher resolution USB sound card that will do 24 bit 96 KHz, 192 KHz, or if you have money to spend, 384 KHz clock rate. The common 44/48KHz devices don't make very good test instruments. External USB is better because sound chips built into a PC or laptop pickup noise from everywhere.   However, I must admit that $15 test equipment is lots of fun to play with. I have LRC meters, function generators, DDS RF generators, return loss bridges, noise generators, etc most of which cost about $15.     -- 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

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Mar 13 11:33AM -0400 > homes and electrical gear.   > Dont they sell the rubber ones anymore, or are they only sold with high > end, costly equipment?   Ah, you're in for a treat: Probemaster 8000 probes, $14 per set last time I hought them:   http://probemaster.com/8000-series-standard   Nice thick gold plating, floppy silicone insulation, HV rated, I could go on. Just buy a couple of sets and you'll bin all your old ones, including the ones that come with Flukes.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

ohger1s@gmail.com: Mar 13 04:44AM -0700 > As far as removing the antenna from your car goes, who cares about the damn radio ? And you don't know where you are going ? When I was young and was stupid enough to run out of gas I would have to walk, perhaps for miles, to get to a gas station where I could borrow a gas can and get some gas. They made me leave my driver's license to give me the damn can. That did not happen alot because I had a good job and did not run out of gas much, but it did happen.   > And there were no cellphones. I could have gotten a radiophone but their range is limited. When you drove fifty miles away the thing usually did not work. So I spent the money on food and beer. Couple times I spent a ton of money treating a bunch of people. That was better than having a radiophone. (they could push the car lol)   > Maybe some would call me a Luddite, but we really are heading to hell in a handbasket.   I don't use the sat radio in my car, but lots of people do. If I spent more time in the car I would pay for the subscription. But I do LOVE the nav, particularly the built in variety. If car hacking comes to be reality, I'll disable the microwave antenna and put my old Garmin back in service.

ohger1s@gmail.com: Mar 13 04:41AM -0700 > >"LOL! I remember when I was just getting started in TV repair and my dad had a 40s radio in the shop for repair. In horror, I saw him put his finger on the "plate" cap of the IF tubes as a poor man's signal tracer. Of course, my first experience with a true plate cap was my finger on a horizontal output tube.. "   > I bet you learned some respect for eletricity.   > For me it was the cathode of a damper tube, which has even more. That SOB burned my finger all the way to the bone, and cauterised it at the same time.   Anybody who does not believe the above should try it themselves. It's happened to me several times - and boy, do those pinpoint burns hurt for days.

MJC <gravity@mjcoon.plus.com>: Mar 13 09:29AM In article <lpnbcc5jrvmdhavmuejutosf76bkjeoj4r@4ax.com>, oldschool@tubes.com says...   > http://c2.staticflickr.com/2/1589/23594985344_c752b64a97_n.jpg   Seems to have a built-in pot, too!   Mike.

jurb6006@gmail.com: Mar 13 12:46AM -0700 Kinda sorry about that, no threat was warranted. I apologize.

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