Sorry for the long post but bear with me.I got up this morning and tuned my FT-857 to 14.185 and listened for BS7H from Scarborough Reef. There he was 5x8 just like several days gone by that were also unsuccessful in my attempts to contact them. 
Anyway, he announced he was listening 14.265 for the east coast so I thought WTF I’ll give it yet another try. I called on the freq. and immediately noticed something wrong. :shock: The power was peaking at only 30-40 watts but the SWR was very low on the tribander as it always is. Everything was great last night! I then put out a carrier and noticed the radio seemed to be cycling at a very rapid pace ie. pulsing the TX signal. I switched to a dummy load and all was fine. Back to the antenna and again the same thing happened. It looked like the SWR protection was kicking in but the SWR was very low. I started checking cables as I thought perhaps the problem was a bad cable before the SWR meter. Hmmmm…..I should have the same results on a dummy load however, I thought, but all was great on a dummy load .I eliminated the antenna switch and switched cables directly. Good on load, bad on tribander with a great SWR. :x I am now starting to beat my head on the desk but wait,….it gets better.
I swept the band with my VFO while TX’ing a carrier into the tribander and notice the problem is only between 14.050 and 14.300. Outside that range things appear to be fine and normal. Great, there goes 20m I thought. Now what could be wrong with the rig that would act like that I thought. The answer was NOTHING as the rig worked fine on all freqs. on a dummy load. Begin round two of the head pounding on desk. :x :x
Now I fire up the Kenwood TS-820S and check things out. No problem whatsoever. Full power out and a low SWR as it should be. I hit the CW key again and then I noticed the external LDG-meter on my FT-857 get super bright! The meter light looked like it was going to supernova whenever I hit the TX button on the Kenwood. I have a home made meter panel on my Tripp Lite power supply for voltage and current and it showed normal current but the voltage went sky high whenever I transmitted. Back to the FT-857. The same thing happened with the power cutback but the meter light remained normal. Back to the Kenwood and the meter lit the room up even in daylight. Round three of the head banging begins. :x :x :x I moved the antenna around from the north where it was to pick up BS7H and swung it around further to the east-northeast to try a contact into eastern Europe. I called CQ and all was fine with the Kenwood. No bright lights or anything. I called on the Yaesu and all was fine. Good power out and everything. I held a carrier and swung the beam around. The problem ONLY appears when between 255 degrees thru NORTH to 35 degrees and ONLY on 20m. Even though it is a tribander antenna 10m and 15m are not affected! ( I forgot to mention I had tried those bands earlier). It would now appear that for some reason I have a REALLY bad RF problem in the shack that is causing the voltage regulator in my power supply to go nuts but only when the beam is pointed in a certain direction and that direction happens to be AWAY from the house. :?: :?: It would not show up when using the Yaesu as when the voltage went up the radio would shut down which would cause the problem to go away and then the radio would come back on and then it would all start over again extremely fast. The average power output from the rig was only reading about 30-40 watts and the average voltage to the meter light was low enough that it did not glow bright. The Kenwood was unaffected by it as it has it’s own power supply built in. I now suspect I have a problem with my cables where they wrap around the rotor and possibly have a short causing the RF problem but I would think I should have a high SWR when that happens. I can understand the problem changing with the antenna position but what gives with the relatively narrow band affected from 14.050-14.300? Now I have to climb the tower and check things out and of course I start my round of 12 hour shifts tonight so things can’t even be considered for at least five days from now. Wish me luck solving this one. I’m going to need it.
:x :evil: :x :evil: :? :x :evil: :x :x
Anyway, he announced he was listening 14.265 for the east coast so I thought WTF I’ll give it yet another try. I called on the freq. and immediately noticed something wrong. :shock: The power was peaking at only 30-40 watts but the SWR was very low on the tribander as it always is. Everything was great last night! I then put out a carrier and noticed the radio seemed to be cycling at a very rapid pace ie. pulsing the TX signal. I switched to a dummy load and all was fine. Back to the antenna and again the same thing happened. It looked like the SWR protection was kicking in but the SWR was very low. I started checking cables as I thought perhaps the problem was a bad cable before the SWR meter. Hmmmm…..I should have the same results on a dummy load however, I thought, but all was great on a dummy load .I eliminated the antenna switch and switched cables directly. Good on load, bad on tribander with a great SWR. :x I am now starting to beat my head on the desk but wait,….it gets better.I swept the band with my VFO while TX’ing a carrier into the tribander and notice the problem is only between 14.050 and 14.300. Outside that range things appear to be fine and normal. Great, there goes 20m I thought. Now what could be wrong with the rig that would act like that I thought. The answer was NOTHING as the rig worked fine on all freqs. on a dummy load. Begin round two of the head pounding on desk. :x :x
Now I fire up the Kenwood TS-820S and check things out. No problem whatsoever. Full power out and a low SWR as it should be. I hit the CW key again and then I noticed the external LDG-meter on my FT-857 get super bright! The meter light looked like it was going to supernova whenever I hit the TX button on the Kenwood. I have a home made meter panel on my Tripp Lite power supply for voltage and current and it showed normal current but the voltage went sky high whenever I transmitted. Back to the FT-857. The same thing happened with the power cutback but the meter light remained normal. Back to the Kenwood and the meter lit the room up even in daylight. Round three of the head banging begins. :x :x :x I moved the antenna around from the north where it was to pick up BS7H and swung it around further to the east-northeast to try a contact into eastern Europe. I called CQ and all was fine with the Kenwood. No bright lights or anything. I called on the Yaesu and all was fine. Good power out and everything. I held a carrier and swung the beam around. The problem ONLY appears when between 255 degrees thru NORTH to 35 degrees and ONLY on 20m. Even though it is a tribander antenna 10m and 15m are not affected! ( I forgot to mention I had tried those bands earlier). It would now appear that for some reason I have a REALLY bad RF problem in the shack that is causing the voltage regulator in my power supply to go nuts but only when the beam is pointed in a certain direction and that direction happens to be AWAY from the house. :?: :?: It would not show up when using the Yaesu as when the voltage went up the radio would shut down which would cause the problem to go away and then the radio would come back on and then it would all start over again extremely fast. The average power output from the rig was only reading about 30-40 watts and the average voltage to the meter light was low enough that it did not glow bright. The Kenwood was unaffected by it as it has it’s own power supply built in. I now suspect I have a problem with my cables where they wrap around the rotor and possibly have a short causing the RF problem but I would think I should have a high SWR when that happens. I can understand the problem changing with the antenna position but what gives with the relatively narrow band affected from 14.050-14.300? Now I have to climb the tower and check things out and of course I start my round of 12 hour shifts tonight so things can’t even be considered for at least five days from now. Wish me luck solving this one. I’m going to need it.
:x :evil: :x :evil:
:? :x :evil: :x :x
When you get things back up to speed let us know what the issue was and how you fixed it. 
