ad: Morse-1

Alternative methods to measure output power

Discussion in 'General Technical Questions and Answers' started by KK6JGJ, Jul 16, 2021.

Tags:
ad: L-HROutlet
ad: l-rl
ad: Left-2
ad: Left-3
ad: L-MFJ
ad: l-BCInc
ad: abrind-2
ad: L-Geochron
  1. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    Actually, the popular modern digi modes like FT8 are modulated, but continuously modulated and can look like a "carrier" on a meter.
     
  2. KK6JGJ

    KK6JGJ Ham Member QRZ Page

    Okay retried the test same frequency across radios and sent Test tone out CW mode. It was picked up strongly by the IC7300. Maybe I made error there before. So it does appear to be getting a signal out. but still does not drive the meter externally.
     
  3. KK6JGJ

    KK6JGJ Ham Member QRZ Page

    Followed your steps 1-6, same behavior on the external meter whether just the antenna tuner or just the watt meter all going to the dummy load, same result nothing on the external meters but ~5W showing on the Power out on Kenwood with an infinity SWR.

    I switched over to 40M in phone range and used AM; with all meters sitting on the Kenwood. This time it worked. It is also working on LSB too on phone seeing all meters and receiving on IC7300

    It also seems during times the day the problem is more or less pronounced. I did use a different cable combo and switched antennas between the two units. All the short lines are professionally crimped LMR400 (except one); The feedlines to antennas are LMR400 too but some of them have my hack connectors on them there could be some issues on these connectors I suppose.

    Additionally I think the MIC control was way down I don't know if this was adjusted down by another mode but raised this up and it seemed to start working on LSB/USB where before it was not. I am going to put initial issue was the MIC control too low; as the CW, AM all produced steady transmitting. It's possible one of the rig controls set this down as well. I think the issue is solved with that configuration change. I never tested this before since I didn't have the external watt meter until this week which is what prompted me to investigate the low readings. Thanks all for the help I think I am good now.
     
    Last edited: Jul 17, 2021
  4. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    Using LMR400 on 40 meters seems to me a really poor choice, unless your transmission line has to be at least 300 feet long.

    "Professionally crimped" connectors don't mean anything to me. Nearly every problem I've ever found at customer sites when I had to go repair things was due to "professionally crimped connectors." For antenna installations customers were paying for, I had to simply refuse to use any of them and always cut them off and installed my own.
     
    W9WQA and WA9SVD like this.
  5. KK6JGJ

    KK6JGJ Ham Member QRZ Page

    Well my crimps need work so professional is still better than mine ;-)

    Regarding the LMR400 interested in why this is a poor choice beyond cost. The runs are probably 200 feet but as I am trying to improve on a poor antenna setup due to a very steep property drop off the side of a hill to work, with my take off angle is already not ideal.
     
  6. K1APJ

    K1APJ Premium Subscriber QRZ Page

    Do you have the proper antenna output selected?
     
  7. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    LMR400 is pretty good stuff, I use it on VHF myself.

    On HF, especially the "lower" HF bands like 40 meters, the difference in performance comparing LMR400 to RG-213/U for a 200 foot run is so small I certainly wouldn't bother mostly due to the LMR400's "stiffness" and flexing/bending difficulty. If you lose 1/2 dB of signal using more flexible and easier to work with cable, nobody can notice that.

    LMR400 crimp connectors still need the center conductor soldered as you really can't effectively crimp a solid conductor. And stripping the dielectric from that solid conductor must be done really carefully to avoid nicking the copper cladding on the aluminum core conductor. The number of vendors I'd trust to do that exactly right every time is zero, which is why I do it myself.

    On 2 meters, however, the "difference" is more like 2 dB in such a length, and I would notice that, so that's where I use it.

    In any case, it sounds like you've got a problem, at least with the Kenwood or "something" besides the antenna. It appears you're in an area with no shortage of hams having technical skills (Oakland should have plenty!) so I'd recommend you try to contact one locally who can visit and determine where the problem is. It's really hard to diagnose issues "remotely."
     
  8. WA0CBW

    WA0CBW Ham Member QRZ Page

    What did you mean by "hack connectors"?
    BB
     

Share This Page

ad: w5yi