# 1.3 GHz FET Probe

1.3 GHz active scope probe with FET input

- **Seller:** [Makerprobe's store](https://lectronz.com/stores/makerprobe), Hamburg, Hamburg, Germany
- **Price:** €24.00 (EUR, before shipping and taxes)
- **Availability:** In stock
- **Categories:** Test equipment, Tools
- **HS code:** 903033
- **Product page:** https://lectronz.com/products/-1300-mhz-fet-probe

## Options

**Accessories**

- No cables
- 2 x u.Fl to SMA jack (female) pigtail, 150 mm (6 inch) [Add €8.00]
- USB to SMA power supply dongle [Add €5.00]
- 2 x u.Fl to SMA pigtail AND 1 x power supply dongle [Add €12.00]

## Links

- [Documentation](https://hackaday.io/project/184924-diy-13-ghz-fet-probe)

## Images

![1.3 GHz FET Probe](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6MTMxMTYsInB1ciI6ImJsb2JfaWQifX0=--a5e6f163ece8302dcdbe890df1abfac3a9754e17/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGciLCJyZXNpemVfdG9fbGltaXQiOls5NjAsNjQwXSwic2F2ZXIiOnsic3RyaXAiOnRydWV9fSwicHVyIjoidmFyaWF0aW9uIn19--970c165836a83091725a1a0fd4f37ce9408da1bf/20240309_154111_mod_crop.jpg)
![1.3 GHz FET Probe](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6OTIwNSwicHVyIjoiYmxvYl9pZCJ9fQ==--c1e40455bbdec49f4c7de060d092ff9bb7ea0874/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJKUEciLCJyZXNpemVfdG9fbGltaXQiOls5NjAsNjQwXSwic2F2ZXIiOnsic3RyaXAiOnRydWV9fSwicHVyIjoidmFyaWF0aW9uIn19--a1419a086f227676aca33a49760ac51e58b523e3/DSC_2024.JPG)
![1.3 GHz FET Probe](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6OTIwOSwicHVyIjoiYmxvYl9pZCJ9fQ==--faf664971363e239bd5df21a052fc32635716a88/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJwbmciLCJyZXNpemVfdG9fbGltaXQiOls5NjAsNjQwXSwic2F2ZXIiOnsic3RyaXAiOnRydWV9fSwicHVyIjoidmFyaWF0aW9uIn19--605f1da017bcbb03ce31845cd0e81d97e3b3c574/2022-05-31T19_09_00.406Z-solderinprobechristops21_0_2ghz_0dbm-1_886px.png)
![1.3 GHz FET Probe](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6OTIxMywicHVyIjoiYmxvYl9pZCJ9fQ==--639355d13142c0db3e593d1539bfceae38db4bbe/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/9849441667425386356.jpeg)

## Description

##### This is the old version of the FETProbe, with limited supply voltage range.
Sold at a discount, while stock lasts.
For the newer V2, visit https://lectronz.com/products/-1-3-ghz-fetprobe-v2
#### What is it?

A 1.3 GHz active scope Probe with FET input and very low input capacitance (about 0.3 pF)  

- **AC coupled**
- minimum frequency: 100 kHz 
- attenuation: 1:10 (1:20 with 50 Ohm termination)
- supply. 5V through u.Fl
- reverse voltage protection
- output through u.Fl
- can be soldered directly to the device under test for minimal lead inductance

For powering, see our [USB to SMA dongle](https://lectronz.com/products/usb-5v-to-sma-dongle) **also available as an accessory option on this page** 

This is a nice low-cost addition to your scope accessory arsenal for cases when the stock probes of a cheap oscilloscope just can't do the job.

#### Why did you make it?
I made this probe to measure oscillators with low load capacitance, when my stock oscilloscope probes would probably detune the circuit too much. There are more use cases - basically everything that can be done with an AC coupled probe with low input capacitance.

See here for a little example: 
[https://hackaday.io/project/184924-diy-13-ghz-fet-probe/log/213125-measuring-an-sx1280s-oscillator-frequency](https://hackaday.io/project/184924-diy-13-ghz-fet-probe/log/213125-measuring-an-sx1280s-oscillator-frequency)