Hello spiff72,
That looks very good.
Your additional tweaks make much sense.
I would like to print it :-)
73, Rudi DL5DA

开云体育

Hey all,

Just wanted to share a 3D printed case I designed around the tinySA.? It is still a work in progress, but I am attaching a few photos of the first print trial, as well as some screen grabs from my CAD.? The CAD shows some adjustments that I have already made (added tinySA logo on the top, and adjusted size of text, added some chamfers around the perimeter to soften the edges, etc).

Once I get something I am happy with I can share the STL files here and/or on Thingiverse.com.

The additional tweaks I intend to work on yet are:

• Refinement of the latch.? It works, but could be better/more robust
• I will likely remove the feature that holds the USB cable.? This was mostly an afterthought, and doesn't work well.? I will probably just wrap a velcro strap around the USB cable and toss it into that area.
• Add a notch in the divider near the top right corner of the tinySA to let the lanyard for the guitar pick pass more neatly into the space where the antenna and USB cable reside

I also wanted to ask the devs if they had any objection to including the tinySA logo on the case as pictured in the screen shot.? I wasn't sure if that would be problematic - I can remove it if I hear any objections or concerns.

Thanks!

On Fri, Jul 23, 2021 at 07:42 AM, Reginald Beardsley wrote:

With a 3rd order low pass Cauer filter on the low port output the spectrum is clean with no spurs above -55 dBc. That's quite good. Certainly adequate for hobby HF design work.

Reg,
? -30dBc was the minimum specification for a lot of the commercial testing that I performed, so -55dBc sounds outstanding to me.

Herb

Herb,

This is not for creating a tracking generator for the tinySA. It's for evaluating mixer performance as a function of drive levels, Vcc, etc.

Just being able to synchronize a pair of tinySAs would provide the tracking generator functionality.

With a 3rd order low pass Cauer filter on the low port output the spectrum is clean with no spurs above -55 dBc. That's quite good. Certainly adequate for hobby HF design work.

The major spurs were the 2nd and 3rd harmonics before I added the Cauer filter.

Have Fun!
Reg

On Fri, Jul 23, 2021 at 12:40 AM, Gyula Molnar wrote:

Herb,

As far as I know, Glenn did not continue, he stayed with the two RF panel versions.

Last July, I started building to replicate the situation at the time. When TinySA was released, it was renamed SimpleSA.

Unlike Glenn, I put it on a panel and managed to revive it with the help of Dave M0WID, designing and building panels.
Because of Covid, it all stopped at the beginning of the year.
If I can see well, Dave continued to plan, but I don’t know what his next plan is.

What I have done with this can show it in pictures.

The TG output has 0-30 dB attenuator and the Low input has 0-30 dB attenuator.

I hope the picture shows the point, I tried to separate the individual units well.

I don’t plan on making a kit or any sales from this.

Gyula,
? Nice project and definitely shows the possibilities of what can be achieved with proper construction. I like the idea of adding a programmable attenuator to the tracking generator output.? Maybe Dave will restart the project at some point as a separate tracking generator module.

? Even better is if hugen was interested enough to offer the tracking generator module as a commercial product.

Herb

Herb,

As far as I know, Glenn did not continue, he stayed with the two RF panel versions.

Last July, I started building to replicate the situation at the time. When TinySA was released, it was renamed SimpleSA.

Unlike Glenn, I put it on a panel and managed to revive it with the help of Dave M0WID, designing and building panels.
Because of Covid, it all stopped at the beginning of the year.
If I can see well, Dave continued to plan, but I don’t know what his next plan is.

What I have done with this can show it in pictures.

The TG output has 0-30 dB attenuator and the Low input has 0-30 dB attenuator.

I hope the picture shows the point, I tried to separate the individual units well.

I don’t plan on making a kit or any sales from this.

--
73, Gyula HA3HZ

On Thu, Jul 22, 2021 at 11:08 AM, Reginald Beardsley wrote:

...*My* tinySA will have TWO tracking generators ;-) I ordered 2 more from R&L. All that's lacking is software to synchronize 3 tinySAs and a GPSDO reference (e.g. RFzero) to a netbook.

Reg,
? When using two tinySA's with an external mixer to create a tracking generator setup, ensure you pay attention to Erik's note about using a preamp and attenuator to increase isolation.? Without those components, your LO mixer driver frequency from the second tinySA will leak back through the mixer to the HIGH OUTPUT port of the first tinySA and restrict your dynamic range to 40dB or less.

? ?Glenn (vk3pe), on the Home Brew Test Equipment group, designed a tracking generator pcb for the DIY version of the tinySA that achieved performance close to a commercial RIGOL spectrum analyzer with tracking generator option - over the same frequency range.? Its too bad Glen doesn't offer a stand-alone kit of parts for the pcb that works with Erik's tinySA.? I think it would be a natural fit that would sell well.

Herb

Well, Herb, funny you should mention this. *My* tinySA will have TWO tracking generators ;-) I ordered 2 more from R&L. All that's lacking is software to synchronize 3 tinySAs and a GPSDO reference (e.g. RFzero) to a netbook.

I designed Cauer aka ellipitical BP filters for 160, 80 and 40 m today using Elsie. I adjust the stop band frequency to put the band edges 2nd harmonic either side of the notch. However, in typing this I realized I should put the 3rd harmonic in the notch. The 3rd is stronger than the 2nd from what I've seen.

Guess I should build both and compare the performance.

Have Fun!
Reg

On Thu, Jul 22, 2021 at 05:07 AM, spiff72 wrote:

Is the white versus yellow text for the top of the screen meaningful, or was that just a firmware update change?

Just a FW update
?
--

Ok. Got it. That's what I was suspecting. Thanks for confirming.

Nagi

The tinySA does leak some RF from the signals used to create the output. Should be sufficient dB down not to have impact on most measurements.
They are always there but the noise floor of you big SA does not show them.
--

The new FW is better able to suppress spurious signals. All looks good

hi Eric, et al;
I had recently purchased a TinySA with FW 1.3111.? I had noticed a weird anomaly with it while testing its sweep generation with my HP 8594E SA at high dBm.? I am not sure if this is an issue with the TinySA at higher dBm or something else.

I created a short YT demonstrating the issue. (just uploaded, it might take a few min for YT to complete its HD processing of the video)

Perhaps Eric or someone here might have a better idea of what might be causing the issue and a mitigation path.

Thanks
nagi

Doh!? Forgot to attach the images...?

Yes - the antenna was connectd in both images - sorry if that wasn't clear.

I took some time today and took equivalent pics in several configurations with both firmware versions, placed in roughly the same location.? I am attaching them - hopefully the filenames are self-explanatory --?
with antenna (multiples with different marker positions), with NO antenna, and with the 30Mhz cal output turned on.

The levels for the 30Mhz signal were:
FW1.1-52: -25.4 dBm
FW1.3-265: -25.0 dBm

I was running under the assumption that those were real FM signals, as the high peak (old firmware) was at about 95.7 MHz (which is a local FM broadcast freq).? I also found that when I brought the TinySA outside my home office/work area peaks on the right end settled down a bit.? There is a LOT of stuff in that office (3D printer which was actively printing), multiple PCs, LED lighting, IoT stuff, etc.

Two additional "newb" questions on this:
- What does the 'afrgnb' represent between the LOW annunciator and the FW version on the display?
- I noticed a difference in the display output between the two firmware versions (yellow top text, and one showed a prefix of '1T' and the other was '1R').? Is this a sign that I may not have had identical settings between the pics?

On Wed, Jul 21, 2021 at 02:56 PM, Reginald Beardsley wrote:

I've been sweeping the 40 m allocation from 7-7.3 MHz with a 3rd order Cauer filter I designed with Elsie for a Chinese Pixie 2 kit in the output line.

With the filter all spurs are down 50 dB or more. Close in phase noise is <-60 dBc measured at an RBW of 100 Hz w/ an 8560A.

I just bought 2 more tinySAs so I can measure mixer performance :-)

I plan to make a suite of BP filters for each of the HF allocations and the common LO & IF frequencies.

This appears to be headed towards an Android tablet connected to three tinySAs, a nanoVNA. Rzero and a Hantek 2D42 DSO-DMM-AWG all linked via USB. That could automate many complex measurements very easily at low cost.

Reg,
? Sounds like an interesting project.? Be sure to post how things work out for you or if you run into any issues that Erik might consider addressing in the next tinySA version.?

? Pretty much the only feature Erik has said is definitely not under consideration for the next hardware version is a tracking generator.? Probably a nice opportunity for someone with hardware design experience to build a tinySA tracking generator add-on accessory.? The nanoVNA does a nice job of measuring filters but does not have the dynamic range to measure the -3dB and -60dB points across its entire range.? With a properly designed tracking generator, I would think the tinySA should be able to achieve 80dB dynamic range on the LOW input port.

Herb

On Wed, Jul 21, 2021 at 02:37 PM, Ted Chesley wrote:

Hi Erik, as a further test, I turned off Channel Power and went to a normal spectral screen. As seen in the attached photo, all is now normal, the marker freq and levels are shown as well as the MK#2/MK#3 Delta. Apparently the Marker readouts are disabled when in Channel Power mode (and perhaps other modes as well).?

?

Ted,
? You have to take into consideration the purpose of the automatic Channel Power Measurement feature which is to measure the percentage of the total power in each band.? Since this measurement is integrated across each band, a single point marker reading is not really applicable.? This is pretty much standard for any? spectrum analyzer with an automatic Channel Power Measurement feature and not particular to the tinySA.

? If you are interested in a in only a single point power measurement then it is more appropriate to disable the Channel Power Measurement and return to normal swept measurements as you did in your second example.

? If you have a special need for measuring marker frequencies that you have turned on while in the automatic Channel Power Measurement mode, and you are connected to a PC, you can read the marker frequencies and level in dBm using the marker?console command.? As an example, marker 1 should return info in the following format,??
? ?
? ? ? ? 1 50 489170379 -95.91? -? marker# index# frequency_in_Hz level_in_dBm

Herb

I've been sweeping the 40 m allocation from 7-7.3 MHz with a 3rd order Cauer filter I designed with Elsie for a Chinese Pixie 2 kit in the output line.

With the filter all spurs are down 50 dB or more. Close in phase noise is <-60 dBc measured at an RBW of 100 Hz w/ an 8560A.

I just bought 2 more tinySAs so I can measure mixer performance :-)

I plan to make a suite of BP filters for each of the HF allocations and the common LO & IF frequencies.

This appears to be headed towards an Android tablet connected to three tinySAs, a nanoVNA. Rzero and a Hantek 2D42 DSO-DMM-AWG all linked via USB. That could automate many complex measurements very easily at low cost.

Thanks for a very fine product.

Have Fun!
Reg