Question about Cobra Mr F75b Marine Vhf Radio Fixed Mount 25watt

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Transmits but does not Receive

I need help trouble shooting my new marine radio and antenna; it appears that I transmit but can not receive calls. I can hear some of the weather channels but that's all. Components are:

  • Antenna is a DIGITAL 528-VW VHF 4FT 4.5DB by Digital Antenna
  • Radio is a COBRA MR F75 VHF W/ DSC25 WATT
Installation was pretty much plug and play not having to cut or splice the antenna coax using the factory installed connector and the power was connected by wing nuts on top of battery.
I have talked with customer support representatives from both companies and they each suggest the the problem is with the other unit. i need to know how to pinpoint the problem; is it installation, radio or antenna? Any help would be greatly appreciated.
thanks keith

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Did you check to see if it's switched on US and not on International?.

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Check your microphone by swapping with another duplicate. If no differance, you will need a SWR meter (standing wave ratio) to find the culprit. It attaches in line of the coax and determinds power out and reflected power. The reading should be 25 watts foward and max of 1 reflected.

Posted on Oct 28, 2008


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