1000MP

Tuner

Problems

 

 

 

 

 

Antenna Tuner is not functioning

PROBLEM: I've now had something happen twice in one year with this 1000MP. Wondering if anyone has seen this and/or has any insight on whether it's operator error, something I have to live with, or something that deserves repair. The tuner works as expected on all bands (I don't have access to 80 or 160 right now, so actually I'm speaking 40-10). The thing that's happened twice is this: After a "normal" session, I turn the rig off. Next time I go to use it, the tuner will not function. I have the 'HI SWR' light, and the tuner does not even attempt to deal with it. Pressing the tuner button gets me a "click" only, and the tuner stops. It happens on all bands. I can reduce the output power to near minimum, and punching the tuner button at least sends the tuner into trying to find a match. When it does, increasing power to full will leave things operational until I either change bands or move frequency by 30kHz or so. Then, I'm right back to the same thing. Tuning at, say 14005, and having full output, then changing to 15m and right back to 20m throws it off.

As I say, this is the second time this has happened. It's as if the tuner has no memory. I'm now in day 3 of this behavior. Antenna is the same as always, no ice/snow/storms. Unfortunately, I cannot recall what I did (if anything) to make it go away the first time this happened! Any ideas would be greatly appreciated.
Steve, N3SL

SOLUTION: On tuner problems, I believe I read that if the 39 tuner memories get filled, The behavior that Steve is experiencing will occur. I think that a memory clear (hold the SUB CE and ENT buttons during power up) will cure it. After re-reading the section on "Automatic Antenna Matching" which begins on page 35 of the owner's manual, the phrase "use it once on your favorite bands" seems to imply something. Here's how I think that the tuner memories work: 1) After pressing the TUNE button once at a specific frequency (and a successful tune cycle occurs), the tuner settings are stored in memory for that frequency segment.
2) When you QSY up and down the band, you'll notice that "WAIT" flashes on periodically. When this occurs, the MP is resetting the tuner slightly for the new frequency, based on the stored tuner info in memory for the nearby frequency. It does this automatically without using up additional tuner memory storage space.
3) I assume that if you later punch the TUNE button again in the same frequency segment that you initially did, the tuner will use the same memory channel it used the first time to store the new tune-up data, resulting in no additional memory space gets used. However, if you hit TUNE again in a different frequency segment, the tuner settings will get stored in a different memory channel -- so now you've used up two of the 39 tuner memories. By tuning VFO-A up and down and watching the WAIT indicator, you can get an idea of how wide these frequency segments are.

 

My suggestion is:
1) Use two tuner memories per band -- one for CW, another for SSB frequencies. Keep a record of the frequencies you do this for.
2) If you use a linear amplifier, the MP will see a different load when using the amp as opposed to going directly into the antenna. If necessary, punch TUNE again with the amp on at the same frequency you used TUNE without the amp in the circuit. The tuner should re-store it's new settings in the same memory channel as before, not using up any additional storage space. Of course, if you go back to barefoot, you'll have to do this again. If you run into the situation that Steve has, I believe that means the 39 tuner memories are used up, and you're trying to tune/store a new frequency segment. The only way I know out of this is to do a memory clear, as outlined above. These are my assumptions. If anyone knows more, we'd all appreciate hearing about it. Earl, K6SE

Supplemental: The only time it is necessary to clear the tuner memories is if you've already filled up all 31 of them and try to do another. You can avoid this problem by using the "tune" mode only twice per band - I suggest once in the CW segment and once in the SSB segment.

The tuner is "smart" enough to track any frequency excursions within a band based on the information it "learned" from tuning info stored for the two frequencies within that band, therefore no additional tuner memories are ever needed (unless you make a change in the antenna used).

Each tuner memory covers only 10.24 kHz. If you QSY outside of the range for which you stored a tuner frequency in memory (by pressing "tune"), the "smart" tuner does a good job of guessing the correct tuner parameters for the new frequency. If you install a new antenna for the same band, you need not use up another tuner memory -- just press "tune" with the VFO set at the exact same frequency as you did the first time. This will overwrite the same tuner memory with the new data.With that in mind, it is a good idea to keep a record of the frequencies at which you wish to store tuner data -- and always use those exact same frequencies whenever you press "tune". This will guarantee that 31 tuner memories will never be filled up. Earl, K6SE

 

 

 

This site was last updated 08/27/07