#557b TinySA Power Levels (don't kill your tiny)

Episode 557b
Make sure you don't over power your TinySA. Check all frequencies and total power.
datasheet: maximum +10dBm input power either port
less than 15VDC offset
My recommendation: maximum 0dBm (1mW) input power
0VDC offset

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[ErikKaashoek]

Both inputs of the tinySA are DC isolated. Don't go above 15 volt

[loueckert]

Great video. I am going to order my tinySA now. Thanks for posting. 73 de KT1R Lou

[Mr.Leeroy]

Could you miss power peaks due to low amount of sweep points available during overview of instrument's entire frequency band and not looking for details with a lower span?
If so, what would be a good rule of thumb frequency range per x sweep points?

[cyberyogicowindler]

Which safety distance is enough to prevent damage to a TinySA Ultra, when I measure with a small (likely a directional) antenna through the air?

I don't own high power transmitters (professional HAM radio etc.), but pointing at an internal DECT or wifi antenna of home electronics (router, laptop etc.) to verify for Bio-EMC that it stays off (or at which frequency range it transmits) will be important. I occasionally adjust TV modulators in old game consoles etc. and possibly I may buy a small CB radio walkie-talkie. The strongest emitting things I own is likely a plasma globe and a violet ray (mini tesla coil, may be among 1 and worst case 10W? RF) those I certainly should not approach too close with the antenna. Which distance is safe and when will I strictly need attenuators?

[bjtaudio]

If you had 5 watts on that 30 db pad it would get very hot really quickly. lol

[_PJB_]

Can I ask what power sensor you are using? Is it CW, modulated, etc.? I’ve searched and searched the numbers on it and I cannot find any reference for PT2-1001 or 20065 power sensor. Thanks!

[stonecoldfyu]

I really like your videos and have this tiny sa. Now I have bout 5 attenuators for me to do some aligning on my cb base station. My question is how do you know the input and output of the attenuators when they are not marked ?

[DonzLockz]

Where would I find an affordable power meter like that or should I look at a different tester?

[mrbambix]

agreed on the power sensor but unlike the tinySA a powersensor can be quite expensive so not available to you. Can you suggest a cheapish alternative to your power sensor?

[vwsandvettes]

So, ignorant question for which I apologize in advance, but can I just run any potential input signal into an RF wattmeter that covers from say, 1mhz to 20ghz, before hooking it up to the tiny sa, which is what a I "think" I saw you do? Then if said wattmeter shows any power level > +10dbm then I would only connect the signal to the tiny sa through a suitable pad or step attenuator? I'm a newbie so apologies for anything I've said that isn't sensible :-) Thanks btw for sharing this video!

[erikas]

Can you connect attenuators just as you like? Or are they directional. Just thought that the SMA-male connector often are input. If the internal resistor network is symmetric, I guess it doesn't matter.

[jspencerg]

This was a great lesson. I am always amused as you consider costs as I do when getting new gear. Well, your power meter is an expensive bit of kit. Fall back to the Chinese alternatives? I need some product reviews for power meter choices.
I'll keep that 30db attenuator handy.

[RichTheNoun]

I was just checking the comments to see how many people were saying to use protection while practicing safe analyzing

[RomanKuechler]

Great. Have ever made a video about cheap (affordable) Power Sensors or Power Meters - if available at all?

[Mark-cexh]

Can I just use a microwatt or microamp and milliwatt and watt analogue meter to check for power output? That in line with a resistor. Sorry I know nothing.

[JohnTarbox]

Is there a relatively cheap (sub $50 perhaps) way of measuring power with sufficient accuracy to ensure the SA will not be damaged?

[RedSummitRF]

I'd like to take a look at the spectrum near some commercial communication towers, like within 100 feet of them. I'd like to do it with the antenna that comes with the tinysa. Obviously I'll have no idea how much power the towers emit, but do you think I should put a pad between the antenna and tinysa? Could I get enough power to kill it just from the towers into the antenna?

[joeteejoetee]

I'd like to agree about using attenuators though out RF signal paths because they stabilize the (supposedly purely resistive) 50 Ohm path.
You will find 2 thru 4 dB attenuation blocks, at every stage, and indeed all the way thru an RF signal chain in professional Avionics = 1GHZ+ and 2KW power.
Attenuation "Pads" offer safe 50 Ohm ports for every next stage, and allow you to test sub-blocks if you DIY and connect aligned amplifiers.
You would not think so, but small Attenuation "Pads" are very often used at the beginning and end of Intermediate Frequency filters (ceramic 3-5 pole coaxial, SAW, Mechanical) because filter response varies wildly with miscellaneous input/output impedances to add reliabilty and ease alignment.

[Bazzawombat]

I hooked up my tiny SA ultra in sig gen mode to my 100w Kenwood to measure rx sens. Took all precautions it would not Tx. I then ordered a 40db 10 w attenuator for $Aud 40 on Ebay in case this ever happened, but, thanks to your video, I will use it on Rx also, thanks for posting, VK2FP/AG7VC

[DanielKirkham-nvxn]

I have designed a local oscillator circuit. I am trying to determine if my LO output is safe to measure with my TinySA. I do not have a power meter. For low frequencies, namely amateur HF bands, would terminating across a 50 ohm load and measuring RMS voltage through a 10x scope probe be a reasonable alternative for measuring power (P=Vrms^2/50)?