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[[File:Modified DFM-17 Radiosonde.jpg|thumb|332x332px|MrARM's modified DFM-17 with a SWD connector and a SMA antenna.]]
The DFM-17 has solder pads for an SMA port and a SWD header.
An [https://adafru.it/4048 Adafruit Skinny SWD SMT] connector and a generic SMA connected was used in the photo.
add dummy load mod and change images to gallery
==Hardware modifications==
====SMA Port to replace antenna:====
The DFM-17 has solder pads for an SMA port and a SWD header. An [https://adafru.it/4048 Adafruit Skinny SWD SMT] connector and a generic SMA connected was used in the photo.
====Minimizing transmit range:====
As amateurs we are not licensed to transmit in the 400-406MHz band, so for testing purposes one should perform this mod. Unsolder the antenna wire and take two 100 ohm resistors and twist them in parallel, then solder them to the center pad and one of the side pads on the SMA footprint. This creates a 50 ohm dummy load for the Si4036 to transmit into. The range is reduced to a couple tens of feet. Also if you are running a radiosonde_auto_rx instance, don't forget to turn it off during testing to avoid feeding erroneous data to Sondehub!<gallery>
File:Modified DFM-17 Radiosonde.jpg|MrARM's modified DFM-17 with a SWD connector and an SMA antenna port
File:Dfm 17 swd and resistors.jpg|Trevor229's DFM with ST-Link SWD pins connected to debug interface and 50 ohm dummy load mod.
</gallery>
