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oldschool@tubes.com: Mar 14 11:39AM -0500 On Tue, 14 Mar 2017 09:19:52 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:     >For 75 ohm RF, I use RG-6/u double shielded CATV cable with F >connectors on both ends. If I need to plug into test equipment, I >have female F to Male BNC adapater.   I've never heard of RG58 C/U. Where would someone buy a small amount of it (Online)? Looking on Ebay, I see the A/U type. And that stuff is mostly pre-made cables with either Pl-259 , or BNC connectors on it, OR large rolls of the bulk wire. (25 ft is the shortest). I could buy a 12ft with BNCs, and cut it in half to make two leads, but that's the A/U type.   I'm thinking this is something that might need to be ordered from a store that sells Ham Radio stuff, but do they sell small lengths and do they ship it?

Jeff Liebermann <jeffl@cruzio.com>: Mar 14 03:03PM -0700 >>connectors on both ends. If I need to plug into test equipment, I >>have female F to Male BNC adapater.   >I've never heard of RG58 C/U.   <http://www.ebay.com/sch/i.html?_nkw=rg-58c%2Fu>   Also known as Belden 8262.   30ft for $36 including shipping and BNC connectors on the ends. <http://www.ebay.com/itm/191993013419> A little pricey but about what I would expect for a long test lead.   It's what's used on test leads and mobile antenna coax cables. Bend the solid center conductor RG-58a/u a few times and it will break. Try to get the type that has both foil and wire braid shields.   >large rolls of the bulk wire. (25 ft is the shortest). >I could buy a 12ft with BNCs, and cut it in half to make two leads, but >that's the A/U type.   Kindly disclose how many feet of the stuff you want and I'll find it for you. How many feet in a "large roll of bulk wire"? eBay is a good place to get short lengths, but not high quality cables.   >I'm thinking this is something that might need to be ordered from a >store that sells Ham Radio stuff, but do they sell small lengths and do >they ship it?   How many feet and I'll find you a source. It's quite common.   Also, you'll need mating BNC, UHF, whatever connectors. I avoid solder type connectors because they like to fall apart. Crimp type are stronger and more reliable. You'll need a crimper: <http://802.11junk.com/jeffl/antennas/Misc/slides/crimpers.html>   100ft for $42 plus shipping: <http://www.l-com.com/coaxial-rg58c-u-bulk-coaxial-cable-stranded-center-conductor-50-ohm-cable>     -- 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

"Ron D." <ron.dozier@gmail.com>: Mar 15 07:33AM -0700 Honestly, we havent; the foggiest of what you want to do.   The generator probably has a 50 ohm output. If it's an FM radio, the input is likely 75 ohms. So, you do need a matching transformer. So, there's generally BNC to BNC and an F connector at the receiver. You can buy adapters to adapt the BNC to F. or BNC to quick F.   RG-58 isn't terribly inflexible. If you want flexibility, then RG174 should work.   At one point, at work we had lots of crimped BNC cables, bought from a reputable manufacturer. Nearly all failed at one point. the broken ones were eventually fitted with clamp BNC plugs. They are not the easiest things to put together, but a resistance soldering tool made it a lot easier.   It also depends where you want to put the adapters.

OOO <ooo@NOWHERE.COM>: Mar 14 10:28AM -0700 USB Phone cord. Molded connectors.   At phone end, cable cracked all around at end of strain relief. Interior wires are OK.   Cannot get shrink tube over connectors of correct size to facilitate repair.   What is the best way to repair this?   Trying to keep at least 2/3 of strain relief at connector flexible.

Adrian Caspersz <email@here.invalid>: Mar 14 06:23PM On 14/03/17 17:28, OOO wrote: > repair.   > What is the best way to repair this?   > Trying to keep at least 2/3 of strain relief at connector flexible.   Sugru   -- Adrian C

Jeff Liebermann <jeffl@cruzio.com>: Mar 14 03:10PM -0700 On Tue, 14 Mar 2017 18:23:53 +0000, Adrian Caspersz   >> What is the best way to repair this?   >> Trying to keep at least 2/3 of strain relief at connector flexible.   >Sugru   <https://sugru.com> <https://sugru.com/tech-gadget/how-to-repair-a-usb-charger-cable> Agreed, but somewhat expensive.   I use hot melt glue when I don't care if it flexes. If I want flex, I use RTV (silicon rubber), Awsome Goo (hard to find), or Shoe Goo.     -- 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

isw <isw@witzend.com>: Mar 14 08:53PM -0700 In article <26qgcc56a1f24tfcqs2585ofcok96dlkr8@4ax.com>, > Agreed, but somewhat expensive.   > I use hot melt glue when I don't care if it flexes. If I want flex, I > use RTV (silicon rubber), Awsome Goo (hard to find), or Shoe Goo.   Shoe Goo and regular Goop (nearly the same thing) work great, as Jeff says, and, if you spit on your fingers, you can mold the stuff neatly around the wire to make a nice strain relief.   Isaac

N_Cook <diverse@tcp.co.uk>: Mar 15 07:49AM On 14/03/2017 17:28, OOO wrote: > repair.   > What is the best way to repair this?   > Trying to keep at least 2/3 of strain relief at connector flexible.   hotmelt glue roughly wrapped around, when cooled , heatshrink sleeving over connector and cord and reheat ,then cut away surplus ooze when cool

bruce2bowser@gmail.com: Mar 14 01:34PM -0700 > sound so bad these days, but that is not the point. Youngers who > want nto this business need to know that there are more than five > volts in the world.   They need 4 or 5 years of union electrical school. It sure helped me.

jurb6006@gmail.com: Mar 15 12:39AM -0700 >"They need 4 or 5 years of union electrical school. It sure helped me"   They don't deal with the kind of voltages we had in the old days. Working on a cellphone is not dangerous like an old tube type color TV. (or B&W for that matter) Things had hot chassis, 5 KV going to the flyback and yoke and all kinds of fun stuff. Alot of stuff runs on a walwart now that removes most of the danger.   I learned respect for electricity at a very young age. My Uncle gave me the airforce primer on it and I read every word. I also learned the hard way at times, but rarely. I also remember that when the print says "DO NOT MEASURE" they mean it, for a couple of reasons. Some things are just too much voltage, other things are sensitive to the load and might fry. I used to get the scope probe just near a horizontal output tube and be able to tell if it is running right. I had a procedure down pat, I almost always knew what was wrong within five minutes, most times in less than a minute.   The damper tube incident was because I kinda slipped or something, I knew damnwell to stay away from that thing.   I also did some electrical work and have seen some things... Shared neutrals for example. I have done older houses where the last guy misidentified the neutral and caused a shock hazard. I had to correct this shit. Nobody else seemed to be able around here.

rickman <gnuarm@gmail.com>: Mar 14 02:31PM -0400 > generator.   > Here is the ebay URL.   > http://tinyurl.com/h5celuc   I haven't read all of the posts in this thread, but I see a lot of confusion of the terms "function generator" and "audio generator". Audio simply refers to the frequency range of the signal generated without saying anything about the manner in which it is generated. But most signal generators output a sine wave and perhaps a square and triangle wave. As others have said, they were often analog circuits that shaped one waveform into another. This is different from an "arbitrary waveform" generator which some seem to be calling a function generator.   An arbitrary waveform generator has a pattern in memory which is played through a DAC to produce any function you wish which must repeat only when the memory capacity is reached.   A DDS is another type of repeating waveform signal generator that also uses digital logic and a DAC. It uses an incrementer to model the phase of a signal cycle which then is translated into a waveform and played through a DAC. If you want a sawtooth wave, you just play the phase value through the DAC. A sine wave may be generated using a lookup table or some simple sine generation functions. Other waveforms can be generated using the lookup table or other mathematical functions. But all these signals must repeat at some period as defined by the amount the phase register is incremented at each clock. In fact, that is the strength of the DDS over an analog signal generator, the frequency of the output signal is very accurately defined.   I'm not sure why you think these devices would not be reliable or are inherently inferior. The Ham community have been using DDS for some time now. Even if they aren't used to directly generate the frequency needed, they can be used as a tunable reference frequency with a PLL to generate a very accurate frequency of nearly any rational value.   --   Rick C

rickman <gnuarm@gmail.com>: Mar 14 07:57PM -0400 > Thanks to all who replied. I read that WIkipedia article, which > explained what these things are, (even though that article was like > reading a legal manual).   Wikipedia often is written by those with a certain level of elitism rather than an interest in explaining topics to all who wish to learn. It is not uncommon for a technical article to be written at such a high level that a reader needs much more than just a casual understanding of the topic.   In my opinion, this is one of the ways Wikipedia has failed.     > dont want to be distracted by computers when I'm soldering. If I do take > any computers in my shop, it's my laptop, and I only do so to view a > schematic on the screen.   How exactly would a computer distract you while you are soldering??? That is very unclear.   If you want to deal with tube circuits you need a buffer between any low voltage equipment and the tube equipment.     > 377's are asking as much just for shipping as I am willing to pay for > the whole thing, and one of them looks like it went thru a war, and is > being sold For PARTS.....   Maybe there's a reason why tube equipment isn't made much anymore?     > tube test gear, besides ebay? There must be other sources.... > It's NOT Amazon, I checked, even though I have never cared much for > Amazon. They just dont sell old stuff like this.   Try connecting with a Ham club. They often use old equipment.     > the US that comes with the matching wall wart for $23. (Which I'd > probably buy, or I will just end up having to spend another $5 or more > to order that wart separately.   The problem with buying wall warts is getting one that does what it says it does. If you type in 5v, 1A for a wall wart on ebay, the first hundred or so units have the same picture, are priced within a nickle of each other and contain a single transistor for the entire active circuit!     > So, the bottom line is that I may buy one of these DDS devices, but I > will still continue to look for the tube type audio generator which is > what I really want in my shop for testing my old tube gear.     You could just insert a tube amp between the DDS and the gear you are testing...   --   Rick C

rickman <gnuarm@gmail.com>: Mar 14 08:02PM -0400 > I suppose I could look this up, but I have other things to do at the > moment, so I am just gonna ask.... What is Arduino? > I'm Old School, so I dont know much about all this new technology.   It's just a single board computer with plug in modules for a wide range of I/O functions. It also has one of the easiest to learn development systems for writing code. If your DDS has a serial port for control the Arduino could be used to make it do more complex functions by changing it from this waveform to that waveform in real time.   --   Rick C

jurb6006@gmail.com: Mar 15 12:22AM -0700 I like my Wavetek 111. It is old, and rated 0.5 % distortion but probably because of caps that goes up at lower frequencies, like 20 Hz. It is a function generator and that is what I would recommend.   For testing of audio equipment, the triangle wave can show distortion quite well. The square wave, at about 1 KHz is quite telling about the frequency response, though not a direct measurement. It is also fun to play with equalization on a 1 KHz square wave. It also has like a half ramp output that might be useful for the development of switching power supplies. It goes up to 1 MHz. I think that is enough.   It was made here. Buying one however is a different story. They are old and most will need some caps, and they are a PITA to work on. They got all kinds of unmarked wires in them between the boards and you really have to watch taking them apart. Screwing that up happened to a friend of mine and the thing still doesn't work, just don't know which wire goes where.   Finding a new US made one might be a bit hard, or pricey. The PC based ones are alright but if you want to "buy American" I doubt any of it is built here. Even if it is, it is probably only assembled here. Probably built by Apex in China or Korea, at least the board. The software might have been developed here.   What you want has been in existence for a long time. Someone said stick with solid state because tubes drift all over the place, I concur. I don't like waiting for some of my older stuff to just warm up the caps, tubes add a whole new dimension to that.   However tube ones might be more destructionproof. If you are about to take a probe from the output and start poking around tube amps you might want to consider that. It will drift, but tomorrow it will still drift. There are places in tube amps where if you want to stick that probe you'll need like a 100K resistor and a cap or it will be stuck at zero Hertz forever. The addition of those components of course will affect the readings as well, so you have to compensate.   But that's my take on it. Also realize when you connect a PC soundcard to a tube amp, it better be well protected. And that is up to you. Resistor, diodes, whatever it takes. Just dumping -40 volts bias into them might destroy them. They need to be clamped.   Bottom line, if you are going to work on old stuff, get old equipment. How old ? Depends on what is out there. If you go to eBay and look for wavetek, look at the ones that have the big knob on the front. And you might as well get a freq counter because those things are not that accurate when it comes to frequency. If you have a scope in good calibration though you can read it on that.   And that's another thing, you might want an old scope. They used to go to 20 V/div which gave you 200 V/div with a 10X probe. Newer ones do not go that high and you would have to get a 100X probe. Using those in AC mode is a PITA because it takes so long to settle.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 14 10:11PM "mike" <ham789@netzero.net> wrote in message news:o34q50$his$1@dont-email.me... >> scrounged a better one on Freegle, I'd just like to know what's going on.   >> Thanks. > it's almost always bad caps.   The 19" hanns-G had leaky front button switches - they were replaced and its fine.   The Dell didn't have a DVI connector, so I just had a quick look - on not finding anything conspicuously obvious, I didn't bother putting it back together.   If I didn't have another spare; I might've tried a bit harder.

bruce2bowser@gmail.com: Mar 14 01:45PM -0700 > Philippines > Russia > Schleswig-Holstein   Schleswig-Holstein is not a country.

"pfjw@aol.com" <pfjw@aol.com>: Mar 14 02:28PM -0700 They would like to think so, and claim a "national" flag. Go figure.   Peter Wieck Melrose Park, PA

bruce2bowser@gmail.com: Mar 14 01:19PM -0700 > some damn hosting but then when I think that then I go "Why ?". > Drawings of some harebrain schem(atic)that I thunk up on a Friday > night after several beverages of my choice ?   I have a beer now and then. Now, that the world's finally gone to 'H'. (and even before then)

"Dave M" <dgminala@mediacombb.net>: Mar 14 01:44PM -0500 dimic wrote: > I have philips PM5165 sweep generator with frequency stability > problem. After it is turned on, it need time to establish constant > frequency.     http://www.jetecnet.com/   Cheers, Dave M

bruce2bowser@gmail.com: Mar 14 09:39AM -0700 e quoted text - On Sat, 11 Mar 2017, Benderthe.evilrobot wrote:   > stick into a computer.   > Maybe an old tower case with no front sockets and stashed under the > desk   There are a myriad of devices that can go into USB ports, many just for recharging only.

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