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I had my FT-818 running for a couple of hours on CW/SSB in the 432 MHz Spring Sprint recently.? I was portable in a hilltop park with an 11 element horizontally polarized Yagi.? All went fine, but I did notice a number of narrow-band digital-sounding non-amateur signals which I don't recall hearing before at that location with my old Microwave modules transverter and a rather broad bandpass filter.? There was no RF source outside my car for a couple of hundred metres, but several radio towers line-of-site within 2 km, and several small cities, also line-of-sight, at greater distances.? The car is a new one since I last operated there on 432, as well...so that's another uncontrolled RFI factor.

This is interesting. I’ve often said YAESU should not make the new FT-817 (now FT-818 I guess) into another scanner. We don’t need a worked all pagers award. What we need is tight filtering for weak signal work without intermod creeping in. The FT-817ND could be better, but wasn’t too bad as it was.



So it sounds like they left the 2m section alone (not great, but not as bad as it could be), but made the 70cm band worse. Too bad. It seems like every other radio out there has a V/UHF front end as broad as a barn door. The 817ND was one of the few not plagued too badly with RX issues.



I look forward to hearing more about the 818. And I may want to pick up a third clean FT-817ND if the 818 does have a weaker front end on 70cm. I don’t need a stinkin scanner, but I do value the 817 for what it is, a very nice weak signal radio for hilltops and rover operations.



Vy73 - Mike - KD5KC.

El Paso, Texas - DM61rt.

SOTA W5T-Texas Association Manager.

NA-SOTA info is at: <>







From: FT817@... <FT817@...>
Sent: Monday, April 29, 2019 9:05 AM
To: FT817@...
Subject: [FT817] Re: FT-818ND new UHF filter performance?





I had my FT-818 running for a couple of hours on CW/SSB in the 432 MHz Spring Sprint recently. I was portable in a hilltop park with an 11 element horizontally polarized Yagi. All went fine, but I did notice a number of narrow-band digital-sounding non-amateur signals which I don't recall hearing before at that location with my old Microwave modules transverter and a rather broad bandpass filter. There was no RF source outside my car for a couple of hundred metres, but several radio towers line-of-site within 2 km, and several small cities, also line-of-sight, at greater distances. The car is a new one since I last operated there on 432, as well...so that's another uncontrolled RFI factor.



I don't know if those signals were in-band spurious emissions or if, as you suggest, they could have been on image (or other out-of-band) frequencies. It would be an interesting experiment to try a bandpass filter at that site and see if those signals disappear. Unfortunately I don't own a good one for 432 MHz.



Thanks for pointing out the image rejection issue...perhaps I should invest in a better bandpass filter if I plan to use the '818 for more serious endeavours on 70 cm.



73,

Steve VE3SMA