receive signal suddenly has become very weak... my QSO buddies tell me my signal is still getting to

John Leonard

Flex 6500 version 1.6.21 software.... receive signal has become very weak. Several of my QSO friends tell me they still hear me fine. Antenna gain settings are still the same. Help! I had a similar problem with my 6300 before I upgraded to the 6500. I'm on the pre order list to get a Maestro.... Help! 

Jim Gilliam

Has the noise floor (nominal -120 dBm depending on location and frequency) reduced a significant amount? If so, could be a blown front end.

Jim, K6QE

Mike va3mw

Pretty big solar storm going on. I heard the same thing as well on both 80 and 40M this morning. http://spaceweather.com/

Duane N9DG

Reminds me what I had happen back on July 14, 2000. The day that my first Ten Tec Pegasus arrived there was a major HF blackout and it couldn't hear a thing. For a little while thought I had a DOA radio. After some more troubleshooting figured out that none of my other radios could hear anything either. And then that there was a major solar event occurring, later found out that it was the biggest solar event in 10 years.

Gary Wise

Are you using an amplifier? Once using my 6500 with my older Heath SB-1000 I had the same issue. Turned out to be carbonized contacts on the Transmit Receive relay in the amp. TX was fine, but receive signals were very weak.

Suggest you simplify your system for test purposes. Connect your antenna directly to your radio, bypassing any amplifiers, antenna switching, power monitoring, etc. If your receive comes back, then you can start looking for the culprit.

73 - Gary - W4EEY

James Whiteway

The HF bands are all but completely dead here. Looking at the solar report on another website there appears to be a pretty big solar storm in progress right now. Guess, I won't have any excuses not to do a couple more "honey do's" today!
james
WD5GWY

John Leonard

Thanks guys.... I did run the antenna straight to the radio and I just got my Kenwood TS-2000 hooked up for an A/B comparison. Same station that is a 55 on the Flex is a 10 over 59 on the Kenwood.

The Band conditions are bad for sure though.

K1UO Larry

Did the RX antenna input selection get changed?  I would reselect them just in case persistence was lost.

George KF2T

Correct antenna selected? Preamp settings? Only one slice open (Two on same freq can produce a null)? WNB & NB off? AGC setting (not "OFF" and slider up enough)? Try a full reset?

Good luck!

DH1RK

Hello John, **** the panadapter and open a new one. Then apply the transverter settings. Cross-check the antenna port and watch the ground noice, also when you externally switch on the preamp. I enjoyed the weak signal operation this weakend with my station up with 1.7.30... 73, Ruediger DH1RK

Tim - W4TME

Try different antenna RX ports.

John Leonard

None of the above suggestions have resolved the problem. The watt meter still says I'm getting 100 watts out but receive is very poor. Last year I made arrangements to exchange the 6300 that had developed a similar problem toward this 6500.

I would like to know what Flex found to be the cause of a similar problem with the 6300 I shipped back? If I recall correctly the person I spoke with thought it might have been a static surge which then caused an antenna relay to "stick" or something along those lines.....

Nothing comes into the shack without going through a Polyphaser first. I unhook the antennas whenever there is a storm in the area or if I'm going to be away....

Again same antenna switched between the 6500 and a Kenwood TS-2000 results in an S meter reading about 3Xs stronger on the TS-2000

  

Mike va3mw

At this point, we need to have some other test gear involved.  The proper way is a signal generator connected to the radio of course.  Beyond that, we are guessing.

That then means that maybe you have someone close by who can help who  might have such a test instrument (even a VNA can do this ).  Or you mad have to ship it in sadly.   Wait until after Dayton and Tim can make his recommendations.

Mike va3mw

George KF2T

One thing - don't rely on an s-meter to tell you true signal levels. While it does appear something is amiss there, comparing s-meter readings between different radios usually can't be trusted to provide good data. The full reset and factory profile didn't change the issue? Try a reset and full power disconnect (right at the power poles) for 5 minutes or so. Since this has happened before, quick question - are you by chance turning the rig off by shutting down the power supply? Or by using the front panel software shutdown ?

John Leonard

You know how a tooth ache that comes and goes and you keep putting off getting a dentist appointment  because you want it to go away on its own, causes more total pain than a sudden "Oh my God this hurts!" tooth ache where you just show up at the office and declare a dental emergency?

That is kind of where I'm at with this 6500. I appreciate all of the above suggestions. Over the past few weeks I have tried several Kenwood to Flex comparisons.... I kept trying to think maybe it is just weird band conditions.... but that's not it. 

What really bothers me is that this is the 2nd Flex  over the past year that has developed this problem in my shack. I have had some good help from local Elmers with station  building... I probably do better than average with either disconnecting or leaving the antenna switch in the center position when I'm not using the radio. 

When I did the problem search for sudden weak receive my post about the 6300 problem I had last year was the only thing that came up... That suggests that this is not a common Flex issue. I really hope that when the Flex guys get back from Dayton they can track down a repair record on the 6300 I sent in last year. Maybe that will shed some light on what is happening....  It's starting to feel like my QTH is jinked.... 

I guess I'll play some radio this evening with the TS-2000.... but after using the Flex radios it is just not the same level of fun. 

ctate243

have you opened a new technical support ticket for this 6500? 

John Leonard

Um no, can I just cut and paste this thread in? I missed where to open a tech support ticket.... I'll look for that now. Thanks

John Leonard

Found the help desk. Thanks again.... I never got around to turning the TS-2000 on tonight.... once you have gone Flex its hard to go back....

ctate243

Very good.  I assumed you knew where it was b/c you had sent in another radio before, but I think you will find the Flex support team first rate.  I will be curious on the outcome I have not experienced a "deaf" flex before or at least one with a reduced sensitivity, and would be interested in hearing the cause.  best of luck!

John Leonard

I live on a ridge top in the NC mountains.... I had a QSO with someone who said high winds (which we have plenty of) can cause a static build up in the antennas, not enough to trip the polyphasers but perhaps enough to damage a Flex? not sure if that is correct or not.... 

I think I read about an alternative to the Polyphasers that was designed to also drain static charges off. Has anyone heard about such an option? 

I really miss using my 6500....

km9r.mike

Well reno is just about the windiest location I have ever seen and one of the driest. I have had zero issues like this with my flexes. I even do not disconnect my antenna nor do I have the rig grounded. Not saying it is impossible, however simply a datapoint where I have not seen the same.

K1UO Larry

Is there anything in the antenna line that is different between the Flex and the Kenwood or are you just moving the coax end from one radio to the other? Is the TX antenna the same one that is being used for RX?

John Leonard

Nothing different.... I have just been switching the same antennas directly into them. 

k3Tim

HI John

I am all but certain wind can cause a static build up on an antenna. A google search of the topic turned up some discussions on this. Having a DC grounded antenna should prevent problems from static but not lighting. If the antenna is not DC ground by design, a dipole for example, adding this feature should not be to difficult.

<+>
 For testing receiver performance a simple calibrated signal generator that puts out 1.0 microvolt is hard to beat. Elecraft makes an inexpensive kit version, crystal controlled with a precision DC power regulator. This makes the 1.0 uV output dead on. I have one and a ham bud' tested it on certified calibration HP SpecAN and the kits output was smack on.

Good Luck,

k3Tim

Mike VE3CKO

I've had problems with polyphasers with similar symptoms, and everybody has problems with switches, even new out of the box, could be a simple as a bad coax from switch to the Flex. Only way to be sure to test two radios is to eliminate possible sources or weakness. Bypass the polyphasers, bypass the switches, use the same cable to go to your 2000 and then try it on the 6500.

Polyphaser would kick in receive after I keyed transmit for a second, so don't use them at this point til I figure which ones are damaged. New switch I took apart clean and bent contacts, all is well.

Tim - W4TME

I believe I know what your issue is.  The PolyPhasers do not drain off accumulated DC (static) voltages.  If they get high enough, they can **** the ESD diodes in the radio (which is what they are designed to do).  The lightning arrestors from Morgan (Previously ICE) and now sold by Array Solutions have the DC bleed off circuit.  I live down the mountain from you in Raleigh and I sware by the ICE designs.  In the 20 years at my QTH, the house across the street has been hit twice and a near strike hit within 300' in the woods behind my house.  The ICE arrestors did their job.

Steve K9ZW

@Tim - thank you for the tip and the reasoning.  As I am putting together the Island antenna farm and shack it is just as easy to provide the extra protection by having a static bleed. 

All ears for any other best practices.  As the Island is largely a big rock with 6-10 inches of topsoil, which is very different than the usual Wisconsin terrain, it perhaps is more like being on the Mountain?

73

Steve K9ZW