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Re: Clarification
¿ªÔÆÌåÓýI work on old tube radios and when I see SMD I think of silver mica disease. ??(SMD occurs in the silver coated mica wafer capacitors in the IF cans as the silver oxidizes and bleeds to the mica edges, producing intermittent shorts) Sorry for the aside. ?Back to listening mode. Nelson Johnsrud Manitowoc WI Nelsjohnsrud@... Sent from Apple Mail mobile? On Nov 28, 2024, at 7:01?AM, Kerim via groups.io <ahumanbeing2000@...> wrote:
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Re: aliexpress freq counters views
¿ªÔÆÌåÓýI have one - they are not outstandingly accurate (mine read 30 Hz low at 10 MHz. Replacing the crystal oscillator with a 0.5ppm TCXO made a big
difference.? Being able to setup the IF to be I only tested it up to 100MHz as I have nothing to generate anything higher. You can vary the LED brightness via the buttons, I have the Green one. I 3d printed a box for it . Dave
On 28/11/2024 10:21, paul larner via
groups.io wrote:
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Re: What list is this again?
On Wed, Nov 27, 2024 at 09:48 PM, wn4isx wrote:
Since I suspect my writing style also irritates people, I've deleted most of my posts and I will limit future posts to topics that are clearly on topic and do my best to avoid forcing thread drift. And I'll probably delete my posts a week or so after everyone has had time to read them. I personally like your style. You talk to others with human feelings and this is rare to happen in these days. ? The fact is that a typical moderator is supposed (by...?!) to act like a humanoid AI robot that has no choice but to execute firmly certain rules without considering anything else. I guess, this was necessary because the universal norm, mainly on the internet, is that every person is bad till proof the contrary. ? Mine is that every new person I may know, or meet is a good guy till he proves me he is not (but even in this case, nothing prevents me to still help him, if necessary, without trying to hurt him in any way). In the worst case, I just leave HIS world, in peace and for good. But let us recall that privilege bad guys hate the presence of peaceful good humans among them. So, the latter ones don't need to leave their world because, sooner or later, they will be banned :) ? Cheers, Kerim ? |
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Clarification
wn4isx
I used SMC, sort of old school term for surface mount components.
Here is a better description of various surface mount things...
What is SMD / SMA / SMT / SMC / SMP / SME? What¡¯s the difference?I use SMC for all those tiny bits.
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Call the language police and have me arrested.
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Re: Possible work bench tops
wn4isx
My friend's daughter snagged one cut out, went out and bought a "piano hinge" and some 2" dowels with hinges and has made a fold against the wall work area for her bedroom. I can see this being a good solution for some situations.
The blanks make perfect drill press mounts. They are 1/2 to 3/4 inch 'marine' plywood.
I used '' because they aren't quite marine grade but the glue is water proof.
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DPDT switch for meter calibration
wn4isx
I've been working on a Simpson 460-3 DVM with analog sub-meter.
There are 2 primary scales, .200V and 2.0V, all the higher voltages are attenuated to one of those.
The zero and +/-2.0V was a breeze, the .200V has been a nightmare. Two controls interact. After switching the Vin bananas a few dozen times I decided enough and rigged a special 'calibration cable' with a 4PDT switch with gold/palladium contacts as a DPDT to reduce any contact resistance.
To change from Vcal+ or - to the opposite means flipping the switch.
I've got it so the V+ is 10.00V, and the V- 10.01, I'd prefer V- to be 10.00 but I'll accept what I've got.
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I obtained this meter because of the analog sub meter. Aligning RF stages is a challenge with a DVM, the analog meter is an ~3 inch wide and ~0.5 inch wide edge meter and very nice for peaking and nulling RF stages.
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My next project is assembling a Heathkit IM-28 VTVM. While labeled as a VTVM it is actually a FET and opamp meter. As I've noted before, I no longer use alkaline cells because of repeated leakage problems and use primary lithium. Lithium cells have a ~10 year life expectancy and don't leak.
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Can you drown in test equipment.?
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Re: Possible work bench tops
On Wednesday 27 November 2024 01:17:01 pm wn4isx via groups.io wrote:
I went with a friend to a shop that specializes in kitchen remodeling. They have many 'blanks' left over after they cut out the space for kitchen sinks. Different shops probably deal with these "blanks" but we were given as many as we could load in a SUV.I have thought about doing exactly that, particularly to mount small machine tools on, once I acquire some. One of these days... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: What list is this again?
wn4isx
Effective immediately I won't delete any messages regardless of my opinion on the adherence to Groups IO rules. I'll let whatever happens happen. ? I think this was my only moderator/administrator action except for asking what to do with an email I received about someone who had been kicked out for s p a m. [That word triggers all sorts of automagic responses by Groups IO] ? In addition I'll block all messages to my email I've been receiving from this group about posts to this section and to the files and links session and I won't interfere with any system created bans for s p a m. ? These steps should relieve any discomfort Gooey and others might have had with my choices and actions. ? FWIW, I never asked to be granted the God like moderator/owner powers and was given no guidelines. I'm sorry if my actions in deleting a file to protect this group caused any angst, it won't happen again. ? I still believe post a link to a site that bypasses the members only log in screen and allows papers protected by copyright by the IEEE was probably the best legal action, probably the worst possible practical step I could have taken within the group. ? Since I suspect my writing style also irritates people, I've deleted most of my posts and I will limit future posts to topics that are clearly on topic and do my best to avoid forcing thread drift. And I'll probably delete my posts a week or so after everyone has had time to read them. ? |
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Possible work bench tops
wn4isx
I went with a friend to a shop that specializes in kitchen remodeling. They have many 'blanks' left over after they cut out the space for kitchen sinks. Different shops probably deal with these "blanks" but we were given as many as we could load in a SUV.
The blanks are a bit on the small size but suitable for mounting items like drill presses, grinders, etc, or a table for a SMC workstation.
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We stopped by Habitat For Humanity and I picked up a rough small table? and I've sat up a dedicated SMC workstation.
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This might be an inexpensive way to obtain work surfaces.
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Re: TFX 18210 mixer used as frequency detector
Yes, Sorry Andy/ I have made of a system which is based on the article attached from this mixer
I tuned the YIG to the resonance of the resonator, then i measured the output of the IF on a scope as shown below. When I tuned to ph2 pase shifter i see the "error voltage" level shanges which need to go back to the YIG "FM" port as shown below. Also i need to make sure that the signal going back to the YIG is something which the YIG could make changes so It will be sensitive to the signal. What is the process of making the PLL lock? Thanks. /g/electronics101/photo/296358/3858955?p=Created%2C%2C%2C20%2C2%2C0%2C0 /g/electronics101/photo/296358/3858956?p=Created%2C%2C%2C20%2C2%2C0%2C0 /g/electronics101/photo/296358/3858957?p=Created%2C%2C%2C20%2C2%2C0%2C0
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Re: Sort of improvised work bench
On Tuesday 26 November 2024 06:38:14 pm wn4isx via groups.io wrote:
One of the members of our shortwave club lives in a small condo where space is a premium.I am currently using such a table for a workbench. There's another bench, 3 by 8 feet, that we built some years back but the surface needs to be replaced, and it's currently in a disassembled state and in storage. I couldn't deal with having to set something over the kitchen table (which is round, anyway, and not near a wall) as my current bench is *way* too cluttered and the shelf at the back of it has way too much in the way of test equipment on it. And forget common card tables, they are way too flimsy. I used one as my work bench when I was 12 and one afternoon a leg buckled and it was a mess. I was too busy dodging the hot soldering iron.When I build a bench I like at least 2x4s for the legs, maybe even bigger... Obviously you have to change the British AC outlets for American ones if you are in America, other nations will require similar adjustments.I picked one of those up that's on a short cord, with outlet, etc. but the test button doesn't seem to do anything. I have yet to investigate that... Take the part on isolation transformer equaling added safety with a large hunk of salt.I have one, and use it seldom. I forget what it's rated at, I'm going to have to look into that. The subject came up in another list (HPAK or maybe Tekscopes?) in the contest of repairing a switching power supply, and I suggested that it might be a good idea. If nothing else, use a pair of similar transformers connected secondary-to-secondary. I have a pile of UPSs to scrap that are probably going to supply some good candidates for this. Or for buck transformers to drop the voltage down a bit for vintage equipment. Right now the voltage here is sitting at 125V, which seems to be pretty typical, sometimes I've seen it go even higher. And Variacs, variable AC power transformer, have some important issues.I built a box to enclose a panel mount unit some years back, which includes a double-pole on-off switch, another switch to select normal or "boost" if I want higher voltage, and a third switch that gives me the option to place a light bulb or a meter to monitor current in series with the output. Only use I've ever found for those DPDT center off switches that were all over the place some years back. Neon indicators show me when power is on and when I've blown the fuse. :-) That variac is only rated to about 2.5A or so. I acquired another one a while back, rated at 4A I think, and the knob that's on it is one that I've seen installed in the wall in some places, used as a light dimmer. I've had some thoughts about putting that in another box with a meter built into it, since I have some meters on hand here, but I haven't gotten motivated enough to move forward on that project. Failure to place a fuse in the secondary of the Variac, a fuse in the hot/primary won't protect the secondary from an overload.Super fast? But they seem to be okay with brief overloads according to what Rod had to say about it... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: hard drives
On Tuesday 26 November 2024 12:35:42 pm C. Michael Stone via groups.io wrote:
I don't run windoze here... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: Sort of improvised work bench
On Wed, Nov 27, 2024 at 02:38 AM, wn4isx wrote:
Is An Isolation Transformer A Safety Measure Or Death Trap?My isolation transformer (500W) was and still is indeed a safety measure for me since many decades ago. Most of my designs are related, in one way or another, to the mains voltage (220V, 50Hz). I also added a 2A fuse at its output, just in case of a short circuit.
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The other measure of safety, I was fortunate to have (around 15 years ago), is a digital scope whose two channel grounds are isolated.??
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Nelson Johnsrud
Gooey