Recently I obtained an old Wawasee meter and digital clock. About half of the numbers in the clock portion are burnt out so I was wondering how difficult it would be to retrofit a small frequency counter such as a Connex FC390 into the space currently occupied by the clock. It would require enlarging the opening in the faceplate of the meter somewhat but nothing severe. I want to do this for two reasons: First, it will eliminate the Siltronix FC-1 display which only has five digits and second it will display the frequency on both transmit and receive, making tuning significantly easier and more accurate.
My question: How to wire it into my old Cobra 135? The FC390 was made for export radios that have a six-pin jack for the counter. My old 135 has no such thing. I do the bulk of my tuning through a VFO. Could I just use a 'T' connector out of the VFO and run a line to the counter? The signal coming out of the VFO isn't very strong and a difference in receive sensitivity when I switch from the crystal bank to the VFO is noticeable. I'm wondering if siphoning off a bit of the signal to the frequency counter will result in decreased sensitivity.
Or should I just try to connect it to the board in the 135? And if so, where?
My question: How to wire it into my old Cobra 135? The FC390 was made for export radios that have a six-pin jack for the counter. My old 135 has no such thing. I do the bulk of my tuning through a VFO. Could I just use a 'T' connector out of the VFO and run a line to the counter? The signal coming out of the VFO isn't very strong and a difference in receive sensitivity when I switch from the crystal bank to the VFO is noticeable. I'm wondering if siphoning off a bit of the signal to the frequency counter will result in decreased sensitivity.
Or should I just try to connect it to the board in the 135? And if so, where?
