Some numbers I keep having to look up / know.

The following numbers are from samples of what I have, not general rules.

• Bulkhead N socket, outside nut, I have most of: 15.8mm threaded part (hole requirement), 20.75mm flange.
• N plug max D: 21mm. (samples: 2)
• PL259 max D: 21mm.
• Male NMEA2000 socket, inside nut: 11.78mm thread / hole needed, 16.80mm flange.

• Grey 8db (paradar?): 28.65mm
• RAK 5.8db: 28.5mm
• ML&S 5.8db: 29.40mm

Carbon fibre pole, 1m: 25mm OD, 1mm wall thickness, feels more than strong enough for an aerial.

Hyperflex 10 - Messi and Paoloni Coax Cable

Loss < 13.4dB / 100m. Probably around 12.6dB, interpolating their data sheet.

They claim it is just a touch better than LMR-400, although a random youtuber tested them and found the loss on the Hyperflex to be much more than specced, and the LMR-400 to be closer to its datasheet.

Hyperflex 5: ~ 24dB / 100m insertion loss. So looks quite usable for a connection to a masthead radio.

N connector loss: probably around 0.15dB. SMA similar. ~0.1 to ~0.2dB.

Hyperflex 10 datasheet

Cable that came with small LoRa aerials, marked T240. About 0.5dB loss including adapters to N type. Diameter more like 0.230 in, but probably an LMR-240 copy.