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SWR Question on new radio.

Tallman said:
First thought is not to check SWR with SSB. If your AM SWR is good then the rest is good too. You are adjusting to a frequency not a transmit mode.
To be honest I have never even heard of any body check SWR with SSB. If you did not
re-calibrate on SSB that would explain why the SSB SWR is double of the AM reading.
Click to expand...
I use a cross needle meter, two of them one meter is between the radio and one meter is after the amp at this time when I put the
tuner in line it too has a meter (cross needle).
I always watch my meters when I Tx. watching for Bad Reflect, then I saw the swr, and went into caution mode.
 
Road Squawker said:
isn't the frequency on AM and SSB the same?

I often inject a single tone into my rig and check the VSWR and/or ALC on SSB.

Post # 2 is correct.

Wanna bet that "certain" coils have been spread out?
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I was going to look in side but started emailing bob and am not going to open the radio as it has been sealed by Bob so I will do as he wants for now....
Bob emailed me and wants me to put a low pass filter on and re test and email him my findings.
 
Mudduckmobile said:
I use a cross needle meter, two of them one meter is between the radio and one meter is after the amp at this time when I put the
tuner in line it too has a meter (cross needle).
I always watch my meters when I Tx. watching for Bad Reflect, then I saw the swr, and went into caution mode.
Click to expand...
Caution is cheaper than finals any day. I play it real cautious too.
 
Mudduckmobile said:
I try to protect my gear....The wife gets mad when I spend to much on radios....
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My wife does the old "tit for tat" routine. Do you have any idea how much yarn she can bring into the house for the cost of two of radios? Icom 7100 and a Yaesu ft-857 have us sleeping dangerously close to a mountain of yarn that trembles when a car drives by the house. One day all of those sheep and alpacas will jump us in our sleep.
 
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Tallman said:
Not 100 % correct. The AM signal would contain the carrier wave, SSB frequency is the carrier wave plus the audio information. SSB will not have a carrier wave if tuned properly. Let's say 27.185 MHz and add 1 kHz audio, the frequency transmitted would be 27.186 MHz upper sideband with no carrier wave.
Still not a good idea to check SWR with the SSB.

If the radio has had the magic power tune, yes the coils have been deformed.
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I told them to only do the conversion mod and alignment. No gold screw drive happy turning.
 
Tallman said:
The best and most commonly accepted method of SWR checking with a radio is AM unmodulated carrier wave. Be it unmodulated CW/RTTY/AM/FM, SSB does not qualify since there is not output without modulation. Modulation is a variable you don't want to introduce into SWR checking. Has the microphone gain been bumped, injected signal level changed, Frequency of modulation changed, ad nauseam. Can we agree to disagree?
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I may have not stated that I do check the swr with out tone. I also watch swr as I tx and saw an reading I had not seen before, an up move of the needle when I was on ssb. With all of my other radios I had not noted an up sweep when modulating.
I understand we don't check vswr on ssb. With my cross needle meter I find myself looking at it a lot as I Tx and I see things I did not see with my old single needle meter.
 
Mudduckmobile said:
I may have not stated that I do check the swr with out tone. I also watch swr as I tx and saw an reading I had not seen before, an up move of the needle when I was on ssb. With all of my other radios I had not noted an up sweep when modulating.
I understand we don't check vswr on ssb. With my cross needle meter I find myself looking at it a lot as I Tx and I see things I did not see with my old single needle meter.
Click to expand...
What you most probably seeing is the result of the "Super tune" and the harmonics will definitely show up that way. Antenna tuned to what ever CB channel and the harmonics are reflected back to the radio. Not a good situation if you don't want to be replacing the finals. Won't happen too soon I hope.
 
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Well this is one for the books.
So from the new radio to the meter is a new jumper (DXE-8xDX003) as each radio has it's own jumper going to the radio, each is marked, and I hook up 1-5 radio's to the first meter.
Anyway, tried the jumper from the ft450d, and it works, did the same test with all jumpers, and I have a bad jumper...
Fixed.
 
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