I live in a situation where I have a friend who is only 1,200 ft. away from my QTH in the same street, for years we both been able to talk with high power (1.5kw) using our radios in the same band and frequency in local nets, even in the same band a bit apart with very minimal issues ( splatter) to each other, now that I change my radio to the 6500 and it don't matter in which band he is , I can't used the radio, we try even in the same band at the same net, and me using the -10db attenuator and the RF gain close to 2 I still can't understand a word he' said and it make's the screen unusable, where you see a single huge spike in the screen and the waterfall turns totally red, how can it be that with the Yaesu , Kenwood , Icom and Elecraft radios in the pass I didn't have a problem and now with this expensive radio I do, btw, the antennas are the same for both and the Amplifiers, so my questions what happen in a situation where you have a few of this radios in a contest station, how can they used them right against each other ?
or is it I have to buy $ 1,000.00 worth of band pass filters for this radio to compare with the supposed inferior brands.
BTW. He still uses his Icom radio and I don't cause him any trouble, He still can be in the same band even if I'm there.
2nd: make sure all your DSP settings are OFF this means ANF, NR, and NB.
I had a NEXT DOOR neighbor before becoming a SK that would run 1.5K Watts on the same band I was using bands and bands and we had NO issues IF the 2 above things were in place especially the DSP being turned off.
I did install a RF voltage limiter in the RX LOOP on the radio once we had parallel wire antennas going back to my far west tower so the wires were about 60' to 100' both being anchored to the tower, so every day was like field day and I could NEVER run the DSP filtering when we were both on the air.
The flex 6700 has a built in limiter that has a relay that clicks that would click on his voice peaks all the time.
We could operate with out a lot of issues as long as we were on the same frequency or at lest on different ends of the same band, I could see his transmissions on different bands by seeing the noise floor increase but we could still operate.
This Field Day, the Phoenix Thunderbird Amateur Radio Club had an all-Flex 6000 series event. We were 4A with a 6700 and three 6300's. We proved that the superior phase noise of the 6xxx series transmitters makes a HUGE difference on in-band use for contesting. We were able to have a 6700 on CW, a 6300 on PSK31, and a 6300 on phone SSB all on 20M at the same time without interfering with each other! Our antennas were all within 400ft, and we were running 100 Watts. Take a look at this screenshot from my 6700.
1) For the 30 or so years I used my Kenwood TS-530SP, I heard birdies and other QRN. What's weird is I still do but I perceive it to be more severe now that I can see it as well. I am not saying that is your issue, just adding a visual dimension to an audible one makes it worse.
2) Do you still have your old radio? Can you swap coax between the two such that it isn't an historical vs current comparison but a true apples to apples comparison?
3) Part of the issue may be the Flex 6000 is, to some degree, a more sensitive receiver. How much more you'd need to consult shereng.com but it likely is significantly more sensitive so it would be more sensitive to adjacent signals.
I am curious about the state if #2 above. If we (you) could remove any sought of doubt. In fact, if you and your neighbor can do a controlled experiment, start with 10W and progress up, i.e. 10W, 100W, 200W, 500W, 1000W etc to see at what point with both radios you get an audible only indication of adjacent signal interference.
Walt - kz1f
I just install an FT-2000 here a few minutes ago with did the same test in all bands with yagis, dipoles with full power and low power 10 watts and with have no issues, in one band he can be in 7.200 and I can be 7.140 with high power or low power and we don't bother each other, in 20 meters the same thing , he was in 14.275 and I was in 14.200 and the splatter was minimal and easy to avoid with the attenuator and the RF gain all the way up never close at all, then we try the both flex radios and with 100 watts , RF gain close to 0 and attenuator in -10 db in 6500 he still comes with a big spike and the waterfall is solid green yellow/red and you can see that from 14.000 to 14.350 so is not a little bit, and is very hard to understand what he said, (mind you that the 6300 don't even have an attenuator) , with a 100W the splatter in other bands is not huge, but when he engage the amp ,on other bands while he's in 20 meters you can still here the splatter and the signal spikes, in all bands, guys I'm not trying to talk bad about the radios , I love them and I wish I didn't live this close to another Ham but is very frustrating that I have to use analog radios instead of SDR to be able to used the radio, imagine been trying to make a contact with a very rare station that you never work before in 15 Meters and where you're about to pull the trigger you get cover by a massive splatter from another station that is not even in the same band but somewhere else's and you can't do nothing about it with the Flex , but with the other inferior radio you won't even notice that other station is there, something is wrong with the front end selectivity here in the Flex radios and it need's to be issue.