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Getting back on the air

Dear Reader,

Last night I tried to get my shortwave station back on the air, when I first switched on I could not hear anyone or anything. I thought that late at night in winter it would be reasonable not to assume that 14 MHz or 7 MHz will be doing very much in Sweden.

So I choose to see if I could tune up the aerial and get a good match, for some reason no matter what the ATU was set to I got the high SWR alarm on my radio. I had horrible thoughts that the radio had malfunctioned, then I choose to try the ATU on the dummy load setting. Again I got a high SWR alarm.

I then grabbed a ohm meter, turned off the radio and I unplugged the aerial lead from the rig. I tried to measure the resistance of the dummy load, connecting the meter at the UHF (m series) plug which goes into the rig I got an infinite resistance. Cursing this I thought maybe I am not making proper contact with the surfaces of the plug.

I then unplugged the other end of the lead, and tried the same test. This time I got a nice 52 ohms. Which is much better. I then choose to measure the lead, the core of the coax was connected to the male spike like bits of the plugs at both ends, but somewhere in the 50 cm of cable and the two M series plugs the braid was there was an open circuit.

Now with a spare patch lead the equipment worked in a more normal way, now looking at the infernal lead I am thinking should I just throw it in the bin or should I repair it. The great problem is knowing where the fault is. If you guess wrong then you could unsolder the wrong plug. I intend to examine the lead using a dip meter and then post the results for you good people to look at.

Now have a happy new year.


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