Re: LT Spice Alternatives
Hi William,
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I am glad my video helped a bit. I am no expert in LTSpice, I use it as a tool (just like I don¡¯t need to know the metallurgical ins and outs of building a hammer in order to use it ;) ), but if you have questions, I will certainly try to answer them.?
Karl Heinz - K5KHK
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Re: SolderSmoke DC Receiver Challenge
On Tue, Apr 22, 2025 at 08:51 PM, bill K7WXW wrote:
The fellow who sold it to me just wanted it out of his storage shed, so I got the whole thing for a hundred fifty bucks, which I was willing to pay for the cabinet, let alone the drawers of semiconductors, capacitors, nixie tubes, connectors, and assorted hardware it was stuffed with.? It was definitely the premier find from my days of haunting swapfests/craiglist/garagesales, looking for parts from the 70s, 80s, and 90s.
What a deal! That must have been fun, going through all the parts when you got home.
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Dave
AA7EE
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Re: LT Spice Alternatives
Karl and Nick,
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It was I who dropped the original post asking about alternatives to LT Spice. Because I don't like to clutter up the threads, if someone does not respond after a day or two, I drop the message.
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In this case, Karl, I am most grateful you provided your response and underlying video. Please know that your video provided a great deal of answers. Actually, it almost directly addressed my grief with LT Spice. Turns out I was having fits with the plotting that LT did and the resulting scales. FOR THE LIFE OF ME, I could not get the starting point, ending point, and ticks of an LPF analysis to cover the full desired range. That said, it lies in the type of analyes done, and the octaves (harmonics) options.?
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I've saved your video, Karl, and careful review should amp up my skill level with LT Spice greatly.
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A side remark, at approximately 1:10 in the video, you remarked that LT Spice was designed by engineers explaining the raggedy interface as opposed to software designed by someone used to creating "normal human" interfaces.
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I am a software developer of over 45 years and remember wondering why Fortran was so obtuse versus the COBOL or C/C++ or other code I wrote! So then there's that!
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Thanks again for your wonderful video and your time and help! I might offer some meager payback:
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..it is a filter design tool somewhat like but not as complete as ELSIE. However, it designs complex filters and also offers to two options/conveniences:
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(1) Will allow one to choose "standard" versus "exact" component values
(2) And allow the designed filters to be exported as either "Spice" or "QUCS" models.
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Vielen dank fur die hilfe! My gratitude for the Rosetta Stone. If OK, I'd like to bounce some questions off you as the mysteries clear.
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--
William, k6whp
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"Cheer up, things could get worse. So I cheered up and things got worse."
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Re: cheap aliexpress LC100a = $13 paperweight?
On Wed, Apr 23, 2025 at 07:39 PM, Tom - VE3PSZ wrote:
Doug how long are your test leads?
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I am using the factory supplied 20cm(ish) leads.
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¡ì97.313?? Transmitter power standards.
(a) An amateur station must use the minimum transmitter power necessary to carry out the desired communications.
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Re: cheap aliexpress LC100a = $13 paperweight?
Doug how long are your test leads? Really long leads can mess up the readings even if zeroed out.
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Re: cheap aliexpress LC100a = $13 paperweight?
Let us know how it goes.? I bought one too but "maybe luckily" can't find it.? I think I only paid $10.00 with free shipping. Jim WB4ILP?
Just to add to the fun, here's a picture with the screen removed.
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Re: Mighty Mike Transmitter
I don't see the feedback path to cause the crystal to oscillate.? If
Q2 is supposed to be a Colpitts oscillator, it is not correct and
missing the feedback capacitors from base to emitter and emitter to
ground.? If you remove C1 and replace it with a 220 pF capacitor,
and add a 100 pF capacitor from the base to the emitter it will
probably oscillate.? You might have to experiment with the size of
R3 to set the drive output of the Q2 circuit.
Hope this helps,
Jim, K8IQY
On 4/23/2025 6:25 PM, Steve Z via
groups.io wrote:
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I've begun building this transmitter (Manhattan style) but
cannot get the oscillator to oscillate. Has anyone built this
before? I also put the oscillator into LTSpice and did not see
oscillation. Does anyone know if this will work?
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Re: Mighty Mike Transmitter
Yeah, I was thinking that it needed those "Collpits" caps.
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Re: Mighty Mike Transmitter
Mike, ? I think there should be 2 caps in series from the base to ground with the midpoint tied to the emitter.? Also, remove the .01uF cap from emitter to ground.? I'll research the values for the 2 cpas, but off the top of my head I want to say 330pF each Bob? WB0POQ
I've begun building this transmitter (Manhattan style) but cannot get the oscillator to oscillate. Has anyone built this before? I also put the oscillator into LTSpice and did not see oscillation. Does anyone know if this will work?
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Re: cheap aliexpress LC100a = $13 paperweight?
Just to add to the fun, here's a picture with the screen removed.
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I've begun building this transmitter (Manhattan style) but cannot get the oscillator to oscillate. Has anyone built this before? I also put the oscillator into LTSpice and did not see oscillation. Does anyone know if this will work?
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Re: cheap aliexpress LC100a = $13 paperweight?
Yup, you're right! I can't even go by the 5% tolerance values I
gave! Sorry, looks like this LC100A meter may indeed be defective.
Steve
On 4/23/2025 2:58 PM, Doug Hendricks
via groups.io wrote:
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Steve the LC100A meter is reading the cap at 292.9pF, which
is not within 5% tolerance.? ?That info is from the picture.?
?Doug Hendricks?
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Re: cheap aliexpress LC100a = $13 paperweight?
Steve the LC100A meter is reading the cap at 292.9pF, which is not within 5% tolerance.? ?That info is from the picture.? ?Doug Hendricks?
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Re: cheap aliexpress LC100a = $13 paperweight?
Thank you everyone for the great ideas.? If nothing else you have convinced me to keep this and figure it out.? Unfortunately it will most likely sit on that shelf until I have more bench time in the fall or winter.? I went on a small aliexpress spending spree figuring 1/2 of what I got would be project starters and not instantly usable things.
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Doug thank you for that link.? I did read in a few other places about replacing L1 but nothing I read had enough detail about what to replace it with.? I took a closer look and I highly suspect it is indeed the pot metal donut they subbed for a proper core.
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Steve very good points.? A real test needs to be my first real first step.
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Curt thank you for the reminder that this should be a simple problem.
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I appreciate the help.
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¡ì97.313?? Transmitter power standards.
(a) An amateur station must use the minimum transmitter power necessary to carry out the desired communications.
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Re: cheap aliexpress LC100a = $13 paperweight?
Doug W
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Not much in these things but an oscillator, a frequency counter and some easy math.?
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I mentioned a simple instrument that makes an L or C measurement, and renders answer in Morse code. It does close enough to 1% marked capacitor values. By analogy, it should be as accurate on RF inductors. So take some more data and see if there is a consistent plus or minus bias. The accuracy here is the precision of its crystal oscillator and its reference inductance and capacitance.?
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The device I used was kitted by George Heron and companions at njqrp. For Atlanticon one year we got this kit for paying our registration. We had to assemble it Manhattan style, they even updated its firmware at the conference. For Not many dollars we got the kit, printed proceedings, laminated badge. Enough door prizes that everyone got one. One year George managed to provide everyone a box lunch. I just ran across my 4 atlanticon badges. LC meter is still QRV.?
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Curt
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Re: cheap aliexpress LC100a = $13 paperweight?
Hi Doug,
The problem is you don't know what your test capacitor's value
really is. You say the cap is 5%, so that could make it 313.5 to
346.5 pF,? and both meters read? the cap within that 5%. Perhaps
find your 1% caps and try the comparison test again.
73,
Steve AA7U
On 4/23/2025 10:39 AM, Doug W via
groups.io wrote:
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Show quoted text
I bought a no name LC100a on aliexpress figuring it was worth
the risk as they offered free returns.? Unless I am really
missing something, it looks like I will be taking them up on the
free return.? I understand my testing method is awful.? 5% caps
using one cheap device to compare to another cheap device should
make most cringe but the Kaiweets meter is usually good.? Those
are 330pf caps.? I have some 1% ones I should dig out but at
this point I doubt it will matter.? I did run and save all the
self calibration routines several times.? This is my fault for
expecting anything better for $13 from a seller called Pure Pure
Grocery Store but sometimes it is fun to roll the dice.? Fun
fact, the price is already up $5 from 2 weeks ago.? Does anyone
with one of these devices know of a trick I might be missing or
as I suspect is this just more garbage made with floor
sweepings?
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Re: cheap aliexpress LC100a = $13 paperweight?
Try this
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It is very interesting and I think you are a perfect candidate for his process.? Please let me know how you get along.
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cheap aliexpress LC100a = $13 paperweight?
I bought a no name LC100a on aliexpress figuring it was worth the risk as they offered free returns.? Unless I am really missing something, it looks like I will be taking them up on the free return.? I understand my testing method is awful.? 5% caps using one cheap device to compare to another cheap device should make most cringe but the Kaiweets meter is usually good.? Those are 330pf caps.? I have some 1% ones I should dig out but at this point I doubt it will matter.? I did run and save all the self calibration routines several times.? This is my fault for expecting anything better for $13 from a seller called Pure Pure Grocery Store but sometimes it is fun to roll the dice.? Fun fact, the price is already up $5 from 2 weeks ago.? Does anyone with one of these devices know of a trick I might be missing or as I suspect is this just more garbage made with floor sweepings?
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Re: LT Spice Alternatives
I must have missed your initial post. I don¡¯t want to dismiss your feelings about LTSpice, but in my experience it is one of the easier Spice flavors. I may have to put this into perspective, my first interactions with computers were via cards, and even though my first version of Spice did not read from a card reader, it still required perfectly formed card input and produced long listings of ASCII output.?
Spend some time with it and go through some tutorials. I cannot promise that you will like it, but you should be able to use it.?
This is a class I did for our local club:
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Hope this helps,
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Karl Heinz - K5KHK?
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On Mon, Apr 21, 2025, at 9:54 PM, chuck adams via groups.io wrote: Steve R. sent me some mica caps rated at +-1% for use as
pseudo-standard for capacitance checks.? Thanks Steve.
I'm sending him some transistors for his effort.
Here is a comparison between his measurements using a
DE-5000, which seems to be popular and mine arrives I am getting a PeakAtlas LCR45 meter tomorrow because between that and the DE-5000, it was less costly.. I will have to get some +/- 1% caps and measure though. -- Ramakrishnan VU2JXN
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k6whp
Jim Kortge, K8IQY
Ramakrishnan Muthukrishnan