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File - FT817 Group Guidelines.txt
The FT817 Group averages over 500 (+/-130 one-sigma) messages
per month. Because the volume of messages is rather large, I would like to remind everyone of a few long-standing FT817 guidelines to follow. Most of you do so already. 1. Civility. (This is practiced well by our members!) 2. Please sign your messages with name and call sign, e.g., Fred - W1XYZ. 3. When replying to a posting (message), kindly delete all unnecessary text including the trailing text. Only leave the text from the prior message to which you are replying ... <snip> the rest. If one desires to read the entire thread, the command [Up Thread] at the top of the message can be used to read the entire discussion. Remember also that a lot of members have slow connections and some even pay connect time or characters rx/tx. This also helps the clarity of your message. 4. When replying to a post, please decide if your comment should be to the entire group of about 10,000 or directly to the author of the post. When you click on "Reply," it goes to everyone. To reply direct (simplex), you should click on the email address following the user ID line at the top of the post. Notice that only a part is shown for privacy. Also, please think about if what you are about to post in reply to the group really should be to the group ... replies like "I sure do agree with that" doesn't add much to the group. Send thoughts like those direct to the poster please. 5. It is fine for members to post something for sale or wanted to buy ... once per item(s). All questions and offers to buy/sell should be made directly to the poster, not to the Group. The member posting the FS or WTB may post that the item(s) was/were sold/purchased. 6. Posting of commercial items for sale by manufacturers or dealers is also fine, but should be done on an infrequent basis. The FT817 members benefit by learning of hardware, software, sales, etc. before it appears in magazines, etc. 7. New members are all moderated until their first posting. If it follows the guidelines, it is approved and the member is change to unmoderated status. This list is a partially moderated list, i.e., only first message is moderated while later messages are monitored after posting. If an unmoderated posting is found by the moderators to have a problem, then the poster is contacted directly to resolve. Actions are taken against those that chronically violate the rules. The reason for this form of moderation is to block spammers from the list and it has been working. 8. Do not add disclaimers to your posts that (1) restrict the ability of other members to use the information you post, (2) claim a copyright to your post, or (3) to claim any type of "rights" as a consequence of another member replying to your post either directly to you or to the group. Thanks to all es 73, Barry - W4WB Moderator |
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Re: FT-818ND new UHF filter performance?
Mike Olbrisch
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 |
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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 |
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FT-818ND new UHF filter performance?
Simon Gale
Hi, I'm considering purchase of a FT-818ND but have some concerns about the UHF performance of the 818 compared to the 817 and would be grateful if anyone has experience of the 818 70cms performance, particularly image rejection. The original 817 had a 3 section helical RF filter for 70cms but it looks like this has been replaced with a two section(?) lumped element filter as seen from the photos in http://radioaficion.com/cms/ft-818-review-and-disassemble/.?? If anyone has seen the schematic I would be interested to know any more details of the new filter arrangement. ? The 817 looked to meet or well exceed the 70cms image rejection spec of 60dB, however the recent review in the Jan QST reported only 38dB for this on the 818 sample they measured (https://static.dxengineering.com/global/images/technicalarticles/ysu-ft-818_gi.pdf).? Perhaps the filter was misaligned in this test sample? Any feedback much appreciated as 70cms is important to me and only 38dB of image rejection is not wonderful. Many thanks Simon M0AZR ? |
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Re: FT-818 Odd SWR Readings on 70 cm
Thanks, Eric.? Assuming the menu is the same in the FT-818 as in the FT-817, it appears that the parameters available there are for the sensitivity of the power foldback (high SWR protection) to the SWR reading, rather than the calibration of the SWR meter itself, but the details I found are a bit sparse.
KA7OEI did point out that on his FT-817 (original) a perfect load gave 2 bars of SWR reading at 5 W on a perfect load.? He found the adjustment instructions for this in the service manual, but it didn't actually work without circuit modifications.? It may be that my FT-818 is just a bit worse! 73, Steve VE3SMA |
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FT-818 new UHF filter?
Hi,? I'm considering purchase of an FT-818 but have? some potential concerns over the capability of the new 70cms RF filter design in the 818 vs the 817.? The 817 had a 3 section helical filter that resulted in very good image rejection performance, mostly exceeding the 60dB spec by a significant amount.? Looking at the 817 vs 818 teardown at it looks like the 818 has replaced the helical filter with something that looks like a 2 section lumped filter (has anyone seen the schematic to confirm please?). I noticed the 818 review in the Jan QST ( ) reported that the ARRL measured a 70cms image rejection of only 38dB, well below the 60dB spec. Perhaps the ARRL sample unit was not correctly aligned, I would be most grateful if anyone has noticed this performance aspect please as 70cms performance is quite important to me. Many thanks Simon M0AZR |
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Re: FT-818 Odd SWR Readings on 70 cm
There are settings in the service menu (the "hidden" menu) to adjust the reflected power sensitivity for HF, VHF, and UHF.? Perhaps those got misadjusted or corrupted (or perhaps the rig came from the factory misadjusted).? I don't remember which menu setting and I am at work so can't check my notes, but you can Google it. Eric Forman KM4VR "Vinum lux Solis est, ab aqua coercita" - Galileo
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Re: FT-818 Odd SWR Readings on 70 cm
Steve, the problem may be parasitic capacitance if the dummy load has multiple resistors due to the resistor lead end caps, the more resistors the worse the problem - check out QST article on UHF dummy load, it shows 11 x 560 ohm resistors in parallel and a small coil - looks like a very good article.
Regards 73 Paul 2E0YOB Paul Simmonds |
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Re: FT-818 Odd SWR Readings on 70 cm
Go for an external meter then.? I'm using my 817 this weekend if I have a 70cm antenna I'll check it but mostly I just use it for HF. Dave G0CER
-- 73 Dave H G0CER |
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Re: FT-818 Odd SWR Readings on 70 cm
I used completely different cables for the front and rear antenna connectors, so I think I have taken the bad cable possibility out of the possible reasons list.? I also operated for a while on 70 cm yesterday and consistently got the 3 bars SWR reading on a well-matched antenna (with another completely different piece of coax).? It seemed to be working fine, apart from the odd SWR reading.
73, Steve VE3SMA |
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Re: FT-818 Odd SWR Readings on 70 cm
Just a thought Steve? - are you using a patch lead to the dummy load - can you swap for another? I've an 817 and really thinking about it never used 70cm except to listen on. Dave G0CER
-- 73 Dave H G0CER |
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FT-818 Odd SWR Readings on 70 cm
My FT-818 shows 3 bars on the SWR meter on 70 cm at the 5 W setting, when connected to a good quality UHF/microwave dummy load.? On 50 or 144 MHz it shows zero bars.? This is true for both front and rear antenna connectors.? The output power is indeed 5 watts, measured on a Coaxial Dynamics meter.? I have tried a couple of good dummy loads. |
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Re: Power pole adapter
Mike Olbrisch
That was exactly it. Some parts had become unobtanium. But they should have left the power levels alone. Only a rank beginner thinks that 6 watts is any kind of useful increase in anything but battery drain. But the loss of the 0.5 watt output will hurt anyone using ?-wave transverters. Instead of using 0.5w as a driver, they now have 1w. That doubles every requirement including battery drain and resistor values in the matching input. And it increases the heat lost in the network.
Using the FT-817 was a very popular way to operate from V/UHF rovers because it is quite small, and was perfect for driving transverters. The only thing constant is change. But sometimes change is not a good thing. Mike – KD5KC -- El Paso -- Texas. The canyons are calling, colorful and deep. But I have promises to keep. And miles to go still in my Jeep... And miles to go still in my Jeep... ADVENTURE: The respectful pursuit of trouble. From: FT817@... <FT817@...> Sent: Sunday, April 21, 2019 10:14 AM To: FT817@... Subject: Re: [FT817] Re: Power pole adapter I believe the main reason for bringing the FT-818 out was some parts are no longer available for the FT-817. It is sort of a "If it ain't broke, don't fix it." By upgrading to parts that are available, keeps the cost in line and that seems to be the case with the FT-818. 73, Joe, K8JP/K5-V31JP On 4/21/2019 8:42 AM, 'Mike Olbrisch' Mike-2020@... <mailto:Mike-2020@...> [FT817] wrote: Good morning Ray. Going over my notes, I show 240,000 radios sold a couple of years ago. I imagine they hit 250,000 radios before the 818 came out. Maybe not….. but only Yaesu knows for sure, and they are not telling. I sometimes wonder if the 818 should be carried as 817 sales, or if it should stand under its own numbers. Is it different enough to make a difference? To me, there is a difference, and not for the better. While the 818 is essentially an updated 817, for my wants the made it a bit worse.. The 817 power levels are 5w-2.5w-1w-0.5w. The 818 runs 6w-5w-2.5w-1w. The difference between 5w and 6w is only useful if you are driving an amplifier that needs the 6w input. Actually on the air, all the 6w does is run your battery flat 20% quicker. But for my ops, the 0.5w level is very miserly on battery use, and is great for driving transverters, a very popular use among V/UHF ROVERS. The FT-818 announcement was a roar. The actual implementation was a whimper! And you are correct. There still is not any other radio out there that directly competes with the FT-817. The FT-818 could have been so much more. It could have beat the KX3. Instead, it was a disappointment. But at least it kept the style out there. It would have been even worse if the 817 were discontinued and no replacement made. Vy73 - Mike - KD5KC. El Paso, Texas - DM61rt. SOTA W5T-Texas Association Manager. NA-SOTA info is at: <> -- Regards, Joe, K8JP/V31JP, Ronnie, Martin & Sidney Pontek 175 Diamond Loch Rd., Apt. 5 Gilmer, TX 75644-9374 U.S.A. or P.O. Box 280, Dangriga, Stann Creek District (Hopkins Village) Belize 903-204-2318 (My TX cellular) 903-884-5990 (Skype telephone number, Belize & TX) Also, K8JP, member FOC-1743, QCWA-LM21894, OOTC-4607, A1OP, SKCC-3171T, NAQCC-5798, Flying Pig-2819, FISTS-7625CC951, A1C-2299, SOC 1075, 10-10 22977, PG1915841, CW Rag chewers #21, Facebook: Joe Pontek Skype: v31joepalooka I am looking for Vibroplex Model X, Double lever and prefer basket cases to restore. LotW [Non-text portions of this message have been removed] |
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Re: Power pole adapter
开云体育I believe the main reason for bringing the FT-818 out was some
parts are no longer available for the FT-817. 73, Joe, K8JP/K5-V31JP On 4/21/2019 8:42 AM, 'Mike Olbrisch'
Mike-2020@... [FT817] wrote:
-- Regards, Joe, K8JP/V31JP, Ronnie, Martin & Sidney Pontek 175 Diamond Loch Rd., Apt. 5 Gilmer, TX 75644-9374 U.S.A. or P.O. Box 280, Dangriga, Stann Creek District (Hopkins Village) Belize 903-204-2318 (My TX cellular) 903-884-5990 (Skype telephone number, Belize & TX) Also, K8JP, member FOC-1743, QCWA-LM21894, OOTC-4607, A1OP, SKCC-3171T, NAQCC-5798, Flying Pig-2819, FISTS-7625CC951, A1C-2299, SOC 1075, 10-10 22977, PG1915841, CW Rag chewers #21, Facebook: Joe Pontek Skype: v31joepalooka I am looking for Vibroplex Model X, Double lever and prefer basket cases to restore. LotW |