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There was an Arduino based 0-30mhz signal generator briefly discussed on the Homebrew group here a while ago.

I wonder if any of the design wizards who have done so much to support the beginner engineer/ amateur enthusiast had ever considered a signal generator in the tinysa /nanovna class?

A signal range up to 100mhz or so, a signal output from 1v down to 1 microvolt and of necessity, minimal signal leakage outside the instrument. I imagine various modulation types and a sweep function could be included but are not essential.

The ability to generate tiny amplitude signals is useful for the amateur communications enthusiast ( and professional too) but my old boatanchor generator is so cumbersome and an awful system to phase-lock the frequency every 25khz made it a pain. The output attenuators was fantastic though, down to 0.1uv.

With the addition of a tiny oscilloscope and a small digital multimeter, I could have a complete lab in my pocket. ?The soldering iron might (literally) burn a hole in my pocket, though.

Steve L. G7PSZ

On Fri, Aug 28, 2020 at 01:45 PM, Stephen Laurence wrote:

There was an Arduino based 0-30mhz signal generator briefly discussed on the Homebrew group here a while ago.

I wonder if any of the design wizards who have done so much to support the beginner engineer/ amateur enthusiast had ever considered a signal generator in the tinysa /nanovna class?

A signal range up to 100mhz or so, a signal output from 1v down to 1 microvolt and of necessity, minimal signal leakage outside the instrument. I imagine various modulation types and a sweep function could be included but are not essential.
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Steve,
? The LOW output signal generator mode of the tinySA meets many of your requirements.

??Low output mode spec:

• Sinus output with harmonics below -40dB of fundamental
• Output frequency range from 100kHz to 350MHz
• Output level selectable in 1dB steps between -76dBm and -6dBm
• Optional AM, narrow FM and wide FM modulation or slow sweep over selectable frequency span
• Optional output level sweep over maximum the entire output level range

? Though not a self contained solution, adding an external 50ohm step attenuator and rf amplifier will cover your high and low level requirements.? Both frequency and level sweep features are a surprise in this class instrument.? Members of my ham club have purchased two tinySA's just so they could dedicate one as a programmable rf signal generator (Yes, both manual and USB programmable control are available).? Terrific performance to cost ratio at cost of $100 for two units before shipping and taxes.

See this page for additional information on the tinSA LOW output mode:

?



? ?There is also a HIGH output mode (240-960MHz) but it does not have the filtering and programmable attenuation of the LOW output mode. It has a square wave output versus the sinus output of the LOW output mode, and is basically a throw-in feature. If you add your own external filtering and step attenuator it increases the utility of the HIGH output mode.

- Herb
? ? ?

I think the Wiki has bloomed since I last looked at it.

I did not realise the sa could do all that. Especially such a range of attenuation. Another 40db (from an external attenuator and one is approaching noise floor (after the attenuator has been validated by the vna).

I think that when the probable next version comes out hopefully with a bigger screen ( I wish I could solder the flexible ribbon with confidence, as a 3.2” screen makes for easier viewing and hardly overlaps the existing case), I will be getting it so that the current sa can be used as a tracking generator and sig gen.

Steve L. G7PSZ

On Sat, Aug 29, 2020 at 03:34 AM, Stephen Laurence wrote:

... I think that when the probable next version comes out hopefully with a bigger screen ( I wish I could solder the flexible ribbon with confidence, as a 3.2” screen makes for easier viewing and hardly overlaps the existing case), I will be getting it so that the current sa can be used as a tracking generator and sig gen.

Steve,
? Several members of my ham club purchased two tinySA's so that one of them could be used separately as a sigen/tracking generator.? The HBTE group (home brew test equipment) recently added a tracking generator daughter board to their small SA design.?

? For a second tinySA used as a tracking source, Erik has suggested adding an attenuator and rf preamp at the LO output of the second tinySA for better dynamic range. That recommendation was actually for a set-up using an external mixer and any external generator.? When using two tinySA's in a tracking generator set-up, I don't believe the extra external components are necessary but the wiki isn't clear about the set-up details.

On Fri, Aug 28, 2020 at 01:45 PM, Stephen Laurence wrote:

With the addition of a tiny oscilloscope and a small digital multimeter, I could have a complete lab in my pocket. ?The soldering iron might (literally) burn a hole in my pocket, though.

Not sure what the best quality and most cost effective "tiny" oscilloscope and small digital multimeter are on the market. Any suggestions that are best to pair with the tinySA and nanoVNA?? ?My Fluke 101 seems like a good fit, though I have no idea regarding a tiny oscilloscope.?

I've been really impressed with the SH72 soldering iron that can be found at times on eBay and any time I've ever looked on Aliexpress.? Looks like they're at an even better price point than when I invested in my few I've been playing with to make even SMD tweezers using two and the "J" style tips.?