Low Power 12 Meters

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  • Updated 4 years ago
Lower power on 12 meters....

Tried this with two different power supplies....an Astron 35 and a SAMLEX 1235M. Each with its own Powerpole strip. No other unit plugged into the strips. West Mountain, not MFJ strips. In other words, two different set-ups. The Powerpole strips are within 5 feet of the power supplies and the original F6500 power cable is used. The Flex 6500 RF Power slider all the way to the right.

Using a LP100A and a Palstar DL2K dummy load, I get the following readings....notice the 12M reading.

160 102W
80 106W
40 103W
30 95W
20 98W
17 98W
15 90W
12 73W *****
10 93W

So the question is why the power drop on 12 m?

Any reasonable answer accepted! Hi Hi!

73/ Regards

Lou N2TU
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Lou N2TU

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  • unsure!

Posted 4 years ago

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K2CM

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I have had this happen to me on a couple of bands. I found a problem with my dummy load, so changed dummy loads and put an external wattmeter in line with the dummy load. This solved my problems.

I have also had problems with occasional low output traced to RF feeback. Ferrite cores and better grounding solved this.
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Lou N2TU

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Ground is excellent....copper braid...and a common junction point...no ground loops...and ferrites everywhere....

I used an external wattmeter...the LP100A...and the dummy load meter was within a few watts of the LP100A, so I am confident the reading is accurate. Also, the readings coincided with readings when the rig was connected to my antenna. Again verifying the accuracy of the readings. 

Trying a different length of coax is out...seeing the readings are almost identical when using the antenna...

Thanks....

Lou N2TU
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KY6LA - Howard, Elmer

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Resonant length of coax. Try a different lengthy of coax
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KY6LA - Howard, Elmer

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Next Guess... Gremlins....
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Jerry Wilk

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Lou, I have the same situation on 12 meters.  Did you ever resolve the problem?   AA7SN