Is this suitable for vhf aerial cable

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Shearwater

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Need to connect aerial to radio and have already a drum of "Samson SATG6W low loss Satellite co-ax 1mm 75 Ohm, twin screened" Oh, colour white. Would appreciate instinct being confirmed as correct.... thank you.
 
The type number will be something like RG-58 for the right cable. This has a solid PVC insulation round the core and a fairly tight copper weave for the screening.( you cant see through to the insulation below)

If you use 75 ohm cable instead of 50 ohm cable then the cable may start transmitting, and you may actually be transmitting low pitched fart noises rather than your voice (the power goes everywhere and interferes with the audio)


CB style 'RG58' aerial cable can also be found which has a loose weave sheath and this is not as good for the VHF use.
 
Your choices are RG58 (5mm), RG8X (6mm), RG8 (9mm), RG213 (9mm). RG213 is best but difficult to work with and expensive so best left for super yachts. RG8 has the same performance as RG213 but with less waterproofing, although still more than adequate. RG8X is a good compromise with considerably less loss than RG58 but lighter and more flexible than RG8. I don't recommend RG58 except for very short runs although it is widely used for cheap aerials.
Look for a high braid coverage, 96% is good, some are in the 80's% and not really acceptable.
 
I am very sceptical about the low pitched fart noises. This phenomenon is known as RF feedback but I imagine it is only possible with AM or SSB transmission where the radiated signal can be detected back to audio in the microphone circuit. FM can not easily be converted back to audio freq in a mic circuit.

The cable is not the correct type. Is it really 1mm as in 1 millimetre diameter? Although decribed as low loss it, loss is not so critical in satelite TV as the signal is amplified at the antenna. 75 ohm cable will work but only in short runs and if you are going up the mast then the losses would I reckon be noticeable. Get the correct cable 50 ohm type.
good luck olewill
 
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