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Ralph Mowery <rmowery28146@earthlink.net>: Oct 11 11:45PM -0400 In article <8r62qe113udhaoakjcriock80njlbm94vj@4ax.com>, etpm@whidbey.com says... > repair but then I would need to learn how to repair it and calibrate > it. Are they hard to calibrate? What sorts of test equipment would be > needed to calibrate one?   The tube tester is not of very much use, especially to someone that is not in the repair business. For those that are, they will usually have a stock of new tubes and it is quicker to just pop one in to see if it solves the problem.   There are 2 basic types in common usage. One is the simple emission tester. It connects most of the elements together except the cathode and checks as to how much the cathode will put out. That will often tell if the tube is weak. The other is the mutual conductance tester. It simulates a circuit and is better.   Most have a shorted element test where you plug in the tube and tap it.   They do not usually need calibration. The easiest way to tell is to check several new tubes and see if they show way up in the good reagon.   Tubes are usually the last components to go bad unless another component causes them to go bad or the filament opens up which an ohm meter will tell.

Fred McKenzie <fmmck@aol.com>: Oct 11 10:12PM -0400 In article <8r62qe113udhaoakjcriock80njlbm94vj@4ax.com>,   > How valuable is a tube tester for > someone who is only, or mainly, going to be messing with audio gear > and the gear for testing audio gear.   If you will be repairing anything with vacuum tubes, then you need a tube tester. I suggest a mutual conductance tester. Mine is a Jackson model 648. It has a built-in scroll of setting information for many older tubes.   You will occasionally find these on E-Bay or at a Hamfest.   > I suppose I could always get a more sophisticated tester that needs > repair but then I would need to learn how to repair it and calibrate > it.   I don't think they are that complicated. Just a simple circuit with a BUNCH of switches and tube sockets wired together. The meter is marked in percent, so you can see how relatively good your tube is.   At some Hamfests, I've seen "calibration tubes" that you could use to check your 100 percent adjustment. I never worried about mine, since I just want to know if a tube is relatively good. Suppose it is only reading 75 percent. That is still a useable tube if you don't have a replacement.   Fred

tubeguy@myshop.com: Oct 11 05:40PM -0500 Cobra 29 cb. The meter never moves on receive, transmit, or ever. An external SWR meter confirms its transmitting and I can hear my test signal on receive. Sort of tells me the meter is blown. I have never tested a meter. What kind of resistance should it have across the terminals? Can I apply a 1.5v AA battery to it to see if it moves?   I also want to know if I can see the receive and transmit on a multimeter? If so, do I use the AC or DC setting?   Thanks

Fox's Mercantile <jdangus@att.net>: Oct 11 06:14PM -0500 > signal on receive. Sort of tells me the meter is blown. I have never > tested a meter. What kind of resistance should it have across the > terminals? Can I apply a 1.5v AA battery to it to see if it moves?   A battery itself is a good way to make sure the meter is blown.   > I also want to know if I can see the receive and transmit on a > multimeter? If so, do I use the AC or DC setting?   Use a DVM set on the DC 1 mA range across the meter. If you read nothing, then something else is dead/broken inside the radio.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Oct 12 03:51AM -0700 On Friday, 11 October 2019 22:17:57 UTC+1, Fox's Mercantile wrote:   > You persist in posting wrong or misleading information to defend > what you original posted that was wrong and/or misleading. > So typical of you.   you sure are the bsing hypocrite.   > present at various places. With the exception of RF amplifier > stages, I have never seen "Current through this device should > be..."   then you lack experience. Some cct diags have it printed on, more often there is a cathode R and a stated voltage or a stated anode voltage. V=IR etc. The size of Rk sometimes gives a rough figure.     > Almost all low lever signal stages operate well below the > published Ip in tube manuals.   > Again the best way to test tubes is "does it work?"   which is pretty much what I said. If stage current is within normal bounds, it typically does work.   > Replacing capacitors to eliminate shorts and high leakage > will solve a majority of problems. Then any "way out of > tolerance" resistors can be replaced.   yup   > Then you can check > for defective tubes.   You might. I power it up to check em, and only test tubes when the stage should work but won't.   > Except the obvious ones, cold (open filament) or red plates. > (Obviously something is seriously wrong.)   or white getter - those are never going to work!     NT

Fox's Mercantile <jdangus@att.net>: Oct 11 04:17PM -0500 > Good advice when being thorough, but time consuming. Just checking Ia or Ik is correct is the quick 'is the stage working' check that gets the job done quickly in most cases. If not obviously you then need to check electrode voltages, Rs Cs etc to determine valve or component failure.   > Valves declared fauly by a tester sometimes still work. Grid shorts can make little difference when Rfault is higher than Rin, eg when the valve is transformer fed. And valves sometimes pass on a tester but won't work in the circuit. A tester is very useful but not the ultimate decider.   > NT   You persist in posting wrong or misleading information to defend what you original posted that was wrong and/or misleading. So typical of you.   Service information usually provides voltages that should be present at various places. With the exception of RF amplifier stages, I have never seen "Current through this device should be..."   Almost all low lever signal stages operate well below the published Ip in tube manuals.   Again the best way to test tubes is "does it work?" Replacing capacitors to eliminate shorts and high leakage will solve a majority of problems. Then any "way out of tolerance" resistors can be replaced. Then you can check for defective tubes. Except the obvious ones, cold (open filament) or red plates. (Obviously something is seriously wrong.)       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Lucifer <LuciferMorningstar@bigpond.com>: Oct 12 11:51PM +1100 >>They start at 5V/0.5A and need negotiation to get a higher output >>voltage or -current.   >OK it shows no voltage, the reason for my question   USB c does not provide voltage.

Arlen _G_ Holder <_arlen.george@halder.edu>: Oct 12 05:18AM On Wed, 9 Oct 2019 19:39:06 -0400, Ken Hart wrote:   > me, especially since my 'backup' ISP uses similar equipment- don't know > if it's Ubiquiti brand, and I don't really want to climb up on my roof > to find out!'   Hi Ken Hart,   Thanks for that purposefully helpful information, as Usenet is a potluck where each of us brings what value we can share with the other members.   While I've repeatedly stated the cost of this powerful equipment is essentially about what people already pay for their SOHO routers and their repeaters, what I didn't say is that the equipment isn't generally to be found in your basic "box" stores (e.g., Best Buy, Target, Walmart, Costco, Home Depot, Frys, etc.).   Regarding the brands you seek, in my experience, two brands stand out: o Ubiquiti <https://www.ui.com> * Mikrotik <https://mikrotik.com>   While they're large corporations that produce many devices, in general o Ubiquiti supplies low-cost well-made stand-alone complete units o Mikrotik supplies even-lower-cost boards where you assemble it yourself   That's why you'll see my Ubiquiti equipment looks like this: <https://i.postimg.cc/YqTk0q1T/ap.jpg>   While my Mikrotick equipment looks like this: <https://i.postimg.cc/DfQJq437/mikrotikrouter.jpg>   > (My primary ISP is DSL via the local telco.)   The good news is that the techniques and equipment described in this thread, work with ANY typical Ethernet connection, such as the ports in the back of your DSL or cable modem, and your home router, and your laptop or desktop PC Ethernet port.   That's the beauty of knowing how to use the tools described here o They work in all common situations (you just need more shelf space)   > My technical background is commercial broadcast engineering rather > Wireless ISP, so the word "antenna" has a more narrow meaning to me, and > it's not something with an RJ-45 connector, hence my confusion.   I agree with you that the use of "antenna" to mean "transceiver + antenna" is a colloquial use of the word, as is the use of "radio" or "router", and even as is the use of "modem", where all are, for our purposes, essentially the same thing.   We have a signal and a means to transmit that signal for miles (LOS). o At just about the same cost as everyone here spends for their home router   But where the home router would be hard pressed to output 20 decibels o And where we can easily transmit up to the legal limit around the world   Where every 3 decibels is twice the power - so that's a LOT of power o Which is why any desktop can connect to an AP which is miles away   You just have to know what we've described in this thread to do it.   > Thank you for your explanation and clarification.   I am always happy to share knowledge, as I feel Usenet is a potluck where adults share among themselves items of useful value to everyone.

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