tinySA using a high impedance probe

Directly using the input of the tinySA to probe an RF circuit may cause to much disturbance in the RF circuit due to the 50 ohm input impedance of the tinySA. In order to have less disturbance I'm using a high impedance probe that uses a FET to convert its 10MOhm, 0.5pF input to a 50 ohm output.
The combination of the probe and the tinySA is demonstrated using a tinySA prototype set up as a conventional heterodyne high IF receiver.
There are many places where you can buy such a high impedance probe, here is one: transverters-s...
More info: www.tinysa.org...

[@wb7ond]

Thanks Eric, saved me from buying the unmodified probe.... Great video..

[@TonyAlbus]

Thanks Erik, Interesting... how did you power the probe?

[@ErikKaashoek]

from a 12V bench supply

[@rickeaston3228]

Can you publish a schematic of the probe you are using. The site in your link doesn't work now because of the war in Ukraine.

[@ErikKaashoek]

Something like this www.google.com/amp/s/www.instructables.com/DIY-1GHz-Active-Probe-for-Under-20/%3famp_page=true

[@rickeaston3228]

@@ErikKaashoek Thanks

[@funkwolf1583]

Hello Erik, first and foremost, thanks for your great vids, I learned a lot from them. Yesterday tho, I tried to update my TinySA but it only shows a white screen after, what I can I do?

[@ErikKaashoek]

See section "If the upgrade fails" of: tinysa.org/wiki/pmwiki.php?n=Main.UpdatingTheFirmware

[@sueserich1587]

Hi Erik, I am pretty much a beginner, I have Tiny SA and a high impedance probe, I only wish to use it on troubleshooting ssb/am 27mhz transceivers, I assume probing the RX receive circuit path should be ok but am not too sure about attenuating the TX Transmit circuit...can you please advise.? Cheers

[@ErikKaashoek]

Join groups.io/g/tinysa/messages where you will find information and advice on how to do this

[@la7yka]

As I understand this is a unity gain probe, with respect to voltage?

[@ErikKaashoek]

There is an AC voltage divider at the input in the form of the 0.5pF input capacitor and the FET input capacitance. This gives the 20dB attenuation

[@Vitaliy1669]

hi where is the link for the sample?

[@ErikKaashoek]

In the description

[@Vitaliy1669]

​@@ErikKaashoek 🤔

[@Vitaliy1669]

@@ErikKaashoek does not open

[@ErikKaashoek]

@@Vitaliy1669 The store I referred to is located in a country that is being occupied by another country and the store is currently closed. There may be something available on ebay.com but the performance is uncertain.

[@Vitaliy1669]

​@@ErikKaashoekThank you!