I'm trying to adjust 4 inductors in a Kenwood ts 440.? The step requires a certain shape of waveform.? How do you make the tiny draw a wave shape??

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Bingo!? That works.? Thanks?

Yes, there is a Max Hold. ?It is under Trace>CalcOff>MaxHold

There is also the ability to “draw” limit lines for a test. ?Example: ?The limit lines shown on Self Test.

Larry

Larry,
I just finished adjusting the VCO 1 feedback loop on my Kenwood TS-440 ham radio.? I used the Max Hold on the Tiny as well as on the Windows app and it worked fine.? Then I thought about what you said about lines.? How do I just have lines instead of frequency spikes?? Not wanting look a gift horse in the mouth......or at least a cheap horse, is there a way to make these traces faster?? I found I would make an adjustment then have to wait several minutes and or restart the trace to see how it affected the result.??
Josh

Hi Josh,

I was referring to setting limit lines like the Self Test does to see if your signal shape fit within limits. ?I misunderstood what you needed.

I suspect what you need is a tracking generator which would give you a frequency response envelope. ?You can do that with extra equipment. ?Erik has done a video as I recall.

Larry
AC9OX

On Mon, Dec 5, 2022 at 01:07 PM, <jsbowman6@...> wrote:

The step requires a certain shape of waveform.? How do you make the tiny draw a wave shape??

I wouldn't have answered your question based on the information given.? You haven't given enough information to provide you with a useful answer.? I would have asked questions to get enough information to give you a reasonable answer to your question.? You have apparently made some adjustments to your radio, but there's no telling whether you have improved anything or not.? It is entirely possible - perhaps even likely - that you have made things worse rather than better.? Your first post tells us that you are adjusting something on a Kenwood TS440, but we have no idea what, and it isn't until 6 hours later that we learn that it is VCO1 feedback loop you have adjusted.? I downloaded a service manual for the TS440, and according to the manual I have, there are a number of steps to go through, several of which do NOT require a spectrum analyzer, then you adjust the 62 MHz BPF, which DOES require a spectrum analyzer - AND a tracking generator, which you don't mention having - then a few more steps, and then you make some measurements at VCO1 in Step 13.? So, we have no way of telling what you have done - good, bad, or indifferent - and the image you posted in your third post doesn't have enough resolution to show us anything at all.? Honestly, if you want help, SLOW DOWN.? Give us more information.? Give us time to ask questions about what you are doing.? How can anybody answer your question if they don't know what your question is?

Jim,
The shape above is the correct shape per the manuals step 11 and the ability, I suppose of the TinySA.? The radio works just fine now after I've repaired it.? I'm simply touching up and checking the rest of it before it goes back to the owner. The original information I gave was really answered.? My follow up question had to do with maybe improving the resolution of the TinySA, not fixing the the Kenwood.? Said another way, I was able to achieve checking step 11 of the Service Manual, it's just as you said the resolution of the trace is rough and I was hoping to find more information on the settings of the TinySA or Windows App that I may have missed.
Josh W4FLI

开云体育

Hi Josh,

to have a better and faster result you can use a noise source or a tracking generator in many measurement setups.. Both have different advantages or disadvantages.

If your test setup includes a frequency translation device, like mix down or mix up of the input signal then you also need a second signal generator and a wideband linear mixer fro the tracking generator or a tracking source with offset capabilities.

Have done such slow statistic sum measurements a lot of time with my SAs, it is sometimes the simplest and best solution, it helps to maximize sweep speed and also keep in mind that the VBW has to be high enough not to partially filter the spike, thus resulting in a low level display. Also it hepls to have a SA with variable sweep speed, then it is sometimes possible to adjust the sweep speed to the source frequency variation in a way that the peaks show up faster and with less gaps.

A completely different test setup is to use a XY display and a wideband detector.

If the source has frequency depended tuning voltage that can be used for x channel defection of a scope you can use a wideband detector with a log amp on the y channel and have a realtime plot. Also a setup I have used many times. For the GHz range the well known Wiltron scalar analyzers with heads are very nice. For the lower frequency range up to 500MHz a log detector based on the Analog Devices chips, like the AD8307 works great.

This has the advantage to be realtime and fast, with the disadvantage of a lower dynamic and the possibility to influence the measurement with out of focus frequency components.

But it is a very great setup for IF filter tuning, because if you have a fast sweeping source this scalar analyzer setup can display a full RF range in some tens ms, like my Wiltron 6647A sweeper in combination with my Wiltron 560 Analyzer. 10MHz to 18.6GHz in? round about 50ms. Love this for such tuning things and cable tests. Because you can see the changes live when shaking a cable or doing stability tests with a small rubber hammer.

All the Best,

Isidro

You guys got me thinking (understand I'm very new to spectrum analyzers).? Comments were made about tracking generators, noise and other types of wave sweeps.? So I found on my Feeltech FY6600 a random noise wave setting and set it from 0.1 MHz to 60 MHz for this band pass filter on the Kenwood TS-440 and got a pretty decent looking single line trace and fairly quickly.? I included the same "settings" sine wave of the same circuit for comparison.? The sine wave sweep takes a good bit of time to form.? Thanks so much for the "brain storming" ideas.??
Josh W4FLI

On Wed, Dec 7, 2022 at 12:07 PM, <jsbowman6@...> wrote:

You guys got me thinking (understand I'm very new to spectrum analyzers).? Comments were made about tracking generators, noise and other types of wave sweeps.? So I found on my Feeltech FY6600 a random noise wave setting and set it from 0.1 MHz to 60 MHz for this band pass filter on the Kenwood TS-440 and got a pretty decent looking single line trace and fairly quickly.?

You have to be very careful when you use a wideband noise generator as a substitute for a tracking generator.? The reason is that the tinySA and tinySA Ultra? have maximum input power limits of +10 dBm and +5 dBm respectively.? This is the total power in the entire signal bandwidth.? A noise generator can have very low power in a narrow measured bandwidth but when you sum up the total noise power it can be quite high.??

Erik explains this and how to measure filters and amplifiers in a short video?


Roger

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Roger, thanks for the video link! ?This is my 1st experience with a spectrum analyzer and you hit the nail on the head in educating me. ?I’m not certain I follow the integration of the 3 screens. ?I’m hoping my habit of using my variable HP 355 attenuator and starting at 40 then reducing to no more than 10 will keep me safe while I learn.
Josh