Tuning up the toys
I wish all of the purchases I made were 100% functional and required no attention or work to bring them up to full function.
For some reason or another an individual will buy some thing brand new to replace what they have. Usually because of a diminished function or they get a good deal on a package deal. Those are the ones I look for.
The MFJ-259 I purchased worked well and came as a package deal with a Kenwood transceiver. The only minor malfunction of the MFJ-259 was that it did not read the impedance properly. Watching the SWR meter of the radio after tuning for the minimum SWR with the MFJ-259 I knew it was working, just not reading right. I connected it to the resistive test load and it was only reading 35 Ohms and I knew better than that. I measured it with my calibrated digital Volt-Ohm meter to be sure.
The test load measured 51.42 Ohms minus the .1 Ohms for the test leads gives an actual resistance of 51.31 Ohms. I called the MFJ customer service to get the alignment procedure for the meter. I was told by one of their techs which potentiometer to adjust for the calibration of the resistance meter. I did not get a full procedure yet, but they are looking.
I opened the unit up and did a quick visual inspection and saw nothing out of the ordinary. I searched the PCB for the location of the pot.
After letting it warm up for about five minutes I tweaked the variable resistor for a reading closer to 50 Ohms on the analog meter. The mechanical zero of the swr meter was too hard to get at and I left it alone.
The meter was reassembled and tested again to verify the accuracy. I was pleased with the result and to verify correctness I used it to tune up my antenna. After keying up the auto tuner did not even budge. I have a field strength meter and use it quite often to check the output of antennas. It did verify that this antenna analyzer does in fact get the SWR down and gets the field strength up higher than just tuning for the lowest SWR.
The Kenwood is flawless by the way!
Here is the procedure they referred me to: http://www.radioaficion.com/HamNews/reviews/54/11341-mfj-259-calibrating.html
I wish all of the purchases I made were 100% functional and required no attention or work to bring them up to full function.
For some reason or another an individual will buy some thing brand new to replace what they have. Usually because of a diminished function or they get a good deal on a package deal. Those are the ones I look for.
The MFJ-259 I purchased worked well and came as a package deal with a Kenwood transceiver. The only minor malfunction of the MFJ-259 was that it did not read the impedance properly. Watching the SWR meter of the radio after tuning for the minimum SWR with the MFJ-259 I knew it was working, just not reading right. I connected it to the resistive test load and it was only reading 35 Ohms and I knew better than that. I measured it with my calibrated digital Volt-Ohm meter to be sure.
The test load measured 51.42 Ohms minus the .1 Ohms for the test leads gives an actual resistance of 51.31 Ohms. I called the MFJ customer service to get the alignment procedure for the meter. I was told by one of their techs which potentiometer to adjust for the calibration of the resistance meter. I did not get a full procedure yet, but they are looking.
I opened the unit up and did a quick visual inspection and saw nothing out of the ordinary. I searched the PCB for the location of the pot.
After letting it warm up for about five minutes I tweaked the variable resistor for a reading closer to 50 Ohms on the analog meter. The mechanical zero of the swr meter was too hard to get at and I left it alone.
The meter was reassembled and tested again to verify the accuracy. I was pleased with the result and to verify correctness I used it to tune up my antenna. After keying up the auto tuner did not even budge. I have a field strength meter and use it quite often to check the output of antennas. It did verify that this antenna analyzer does in fact get the SWR down and gets the field strength up higher than just tuning for the lowest SWR.
The Kenwood is flawless by the way!
Here is the procedure they referred me to: http://www.radioaficion.com/HamNews/reviews/54/11341-mfj-259-calibrating.html
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